COVER CROP CONFUSION

How Much Soil Organic Matter?

In last week’s blog I kept jumping the fence about cover crops. First I extolled their benefits. Then I wrote that they’re probably unnecessary in my heavily composted ground and possibly to blame for poor growth of some corn and tomatoes. Finally, I wound up stating that I do grow some cover crops anyway. No wonder I caused some confusion.
Oat cover cropsAll this prompted one reader, Peter, to comment with some specific questions that might also be of interest to some of you. I will now try to answer them.

His first question was: “How is percentage of organic matter in the soil determined.” “Organic matter” is carbon compounds; as such they can be oxidized, and when this happens they are lost from the soil as carbon dioxide and water. Microorganisms do this naturally in any soil as they feed on organic matter, in so doing releasing minerals associated with the organic matter in forms that plants can use for nourishment.

The way to test the percentage of organic matter in the soil is to weigh a sample, oxidize the organic matter, then weigh it again to measure the loss. Oxidation can be done by burning the sample at high temperature. Another way is to chemically oxidize a weighed sample using potassium dichromate and then measure how much dichromate is left after the reaction. (The latter reaction is more accurate than burning because carbonates in a soil will also lose carbon dioxide when heated, affecting the final weight.) 

Peter, I suggest against determining the percentage organic matter of your soil in your kitchen. Soil labs generally include percentage organic matter along with other test results. (I cover soil testing in my book Weedless Gardening.)

Peter also reported that his soil tests very high in phosphorus, potassium, magnesium, and calcium. Soils to which have been added lots of organic matter typically test very high or excessive levels of phosphorus and potassium. That doesn’t present a problem, possibly because, as I wrote last week, “Conventional soil tests are for mineral soils, not soils that are very high in organic matter.”

As far as the high levels of calcium and magnesium, I’m not sure about that. Excessive applications of dolomitic limestone would cause that, and that would also be reflected in a high pH.

To Cover Crop or Not to Cover Crop, That is the Question

Now for a more difficult question. Why do I plant cover crops if I don’t think they’re of benefit in my soil? I guess that’s because I’m aware of the known benefits of cover crops. If nothing else, the cover crop obviously protects the ground’s surface from the pounding of raindrops and wide swings in temperature. Even if I don’t notice any positive impact, they may be there, more subtly. And then there are the still unknown benefits of cover crops.
Cover crop, 3 beds with cabbageThe major, consistent negative impact of my late summer of fall planted oat cover crops has been to increase the number of weeds the following spring, specifically henbit (Lamium amplexicaule). For the past couple of years I’ve dealt with that problem by tarping those beds in spring for a couple of weeks or more. Or, not as good, just pulling out the henbit.

Because I only cover crop beds that are no longer needed for vegetable plants towards the end of the growing season, growing the cover crops doesn’t take up space in which I could otherwise grow vegetables.

Buckwheat sprouting in greenhouse

Buckwheat cover crop in greenhouse

It’s also almost no trouble to sprinkle the oat seed over the bed before laying down the inch of compost each bed gets every year.
Sprinkling oat seed
And finally, I have to admit that I like the lush green look of the oat leaves, the leaves maintaining that look almost until the first day of winter. And even after that, they flop down on the ground, dying, but then hiding the brown compost beneath a tawny blanket.

Rye cover crop at Chanticleer Garden

Rye cover crop at Chanticleer Garden

Timely Planting

Last question: “When is the latest time to plant the cover crop?” Cooler weather and diminishing sunlight dramatically slow plant growth in autumn. Oats like that cool weather, and will germinate and sprout pretty late in the season. But there comes a time when so little growth will ensue that oats or any other cover crop is not really worth planting.
Oat cover crop sprouting
Here, about half way up New York’s Hudson Valley (USDA Hardiness Zone 5), I figure on the latest date to make planting a cover crop worthwhile is about October 1st.
Oat cover crop in October

CLOTHE THE GROUND

Something Good for the Soil

Soil has been called “the skin of the earth.” That “skin” nourishes much of life here, so let’s take care of it. Which is one reason for cover crops, that is, plants grown not directly for us, but specifically to maintain or improve soil health. Typical cover crops include rye, oats, buckwheat, clovers, and other mostly grains or legumes.
Oat cover cropThe most obvious benefit of a cover crop is the protection it affords the soil from wind and rain, either of which can carry away the most fertile surface layer. Also protection from temperature extremes. Another benefit is that cover crops can suppress weeds. Less obvious is cover crop plants’ ability to grab onto and bring back up to the surface layers nutrients that rain might otherwise wash beyond roots into the groundwater.

Buckwheat cover crop

Buckwheat cover crop at Chanticleer

Some effects are even more subtle. Substances oozing from plant roots feed microbes and also bind soil particles to create small and large pores to create a good balance of air and water in the ground. Cover crops also can increase levels of all-important soil organic matter, which benefits plants and soils nutritionally, physically, and biologically in both known and unknown ways.

But Does My Ground Need It?

Despite the benefits of cover crops, you’ll rarely see them in my vegetable garden. Mostly, that’s because the beds are usually packed full of growing vegetables from very early to very late in the growing season. There’s nowhere to plant a cover crop! The vegetable plants themselves provide the same benefits as would a cover crop, especially since I plant at very close spacing, close enough, usually, to hide bare ground.

Bed of broccoli & endive

Bed of broccoli & endive

Planting cover crops in my garden to increase soil organic matter would be like taking coals to Newcastle. For decades, every year I’ve laid a one-inch blanket of compost over all my vegetable beds. (My book Weedless Gardening describes the whole system of soil care.) The result is soil organic matter levels, last time I tested, at about fifteen percent. No need for cover crops to boost my soil’s organic matter content.

Fifteen percent organic matter is very high. A typical, very good agricultural soil, such as the virgin Midwest prairies, was about five percent organic matter.

Then again, could fifteen precent be too high? Very high levels of organic matter lead to soil tests registering excessive levels of phosphorous and potassium. Traditionally, phosphorus was thought to be so tied up chemically in the soil that it would stay put, but some recent research indicates that water can push some phosphorus into the groundwater if phosphorus levels are high enough. 

Conventional soil tests are for mineral soils, not soils that are very high in organic matter. A soil with around fifteen percent organic matter would better be called a “growing medium” rather that a “soil. Soils naturally this high in organic matter are classified as histosols, commonly called bogs, peats, or moors. Such soils, in contrast to my garden soil, are typically low in plant nutrients.

An obvious way to assess soil management is — duh — to look at the plants and their growth. Everything looks fine.

Problem? Maybe, Maybe Not

Except for a couple of strange goings on in one of my two vegetable gardens. In one bed, planted this year to early turnips and lettuce, now in corn, the corn in half the bed is stunted. (The turnips and lettuce did fine.) Stunted cornIn another bed, tomatoes are doing fine, but are not as vigorous as they should be as compared with another bed of tomatoes in that garden.

Weakly & vigorous tomato bedsMy notes indicate that both beds received their annual blanket of compost, just like all the other beds. Last fall, when the compost was applied, I also sowed cover crops in those beds. Rather than my usual oats cover crop, which winter-kills so integrates well with my no-till system, I sowed crimson clover along with the oats. Why crimson clover? Because it’s pretty when it blooms in spring.
Crimson clover
Crimson clover is allelopathic. Allelopathic plants can biochemically suppress growth or germination of nearby plants; the clover could have adversely affected growth of tomato and corn. Of course, only half the corn bed is stunted but clover germination, if I remember correctly, wasn’t uniform in that corn bed. I’ll file all this in the back of my head for future investigation.

Then again, oats, is also allelopathic, as are rye, sunflower, sorghum, and many other plants, including, most famously, black walnut. Allelopathy is often very specific, an allelopathic plant inhibiting the growth of only some species of plants. Said allelopathic plant might even promote growth of other plant species. Time, usually a couple of weeks, after an allelopathic plant is killed or removed, usually rids the soil of any allelopathic effect.

For completeness, I should mention that the corn and tomato bed problem could be traced to erratic behavior, this year, of my drip irrigation system, which has now been corrected.

I’m going to continue occasionally planting cover crops and will monitor more closely any positive or negative effects — in my garden. As they say in so many arenas: “Your results may differ . . .”

SENSUAL THINGS, AND WATER

Heady Nights

It’s difficult to work outside in the garden these days, especially in early evening. No, not because of the heat. Not because of mosquitos either. The difficulty comes from the intoxicating aroma that wafts into the air each evening from the row of lilies just outside the east side of my vegetable garden.
cat and lilies
These aren’t daylilies, which are mildly and pleasantly fragrant. Wild, orange daylilies are common along roadways and yellow and hybrid daylilies, often yellow, are common in mall parking lots. (That’s not at all a dis’; the plants are tough and beautiful, and I’ve planted them also.) They’re also not tiger lilies, which lack aroma and sport downward turned, dark red speckled orange flowers with recurved petals. 

My fragrant lilies are so-called oriental hybrid lilies, which are notable for their large flowers and strong fragrance. My favorite among those I grow is Casa Blanca. The flowers are large and lily white (what’d you expect?) except for the threadlike, pale green stamens emerging from their centers, with dark red anthers capping their ends.

Casa Blanca would be worth growing just for the look of the flowers; the fragrance, very sweet and very heady make this bulb a must-grow. Not for everyone, though. A few people dislike this fragrance. For some people it’s more than just stinkiness, the aroma causing nausea, dizziness, or congestion.
Casablanca lily in the garden
Casa Blanca’s stems can rise to about four feet tall, their upper portions circled with almost a dozen of those large blossoms in various stages of ripening. Some years, staked, persimmon orange, Sungold tomatoes grow in that bed, and the tomato and lily plants looked very pretty mingling together. (Tomatoes were, after all, once grown as ornamentals.) 

This year I’m growing kale in that bed which, besides good eating, provides a frilly base from which the lily stems rise.

In Good Taste

Turning to another of the senses . . . taste. Blueberries. They are among my most successful fruits and, as usual, the plants’ stems are bowing to the ground under a heavy load of berries this time of year.
Blueberries galore
Not to brag, but the average yield of a blueberry bush is 3 to 5 quarts. My blueberry bible, Blueberry Culture (1966), states that “proper cultural practices can increase the yield to as much as 25 pints per bush.” I average about 18 pints per bush, with some bushes yielding as much as 24 pints. Organically grown, of course.

I credit my good yield to periodic additions of sulfur to maintain acidity of pH 4.0-5.5, timely watering with drip irrigation especially the plants’ first few years, topping up of existing wood chip, wood shavings, or leafy mulch each fall with an additional 3 inch depth of any organic, weed-free mulch, and pruning every spring. 
Bunch of blueberries
In year’s passed, I also added soybean meal for extra nitrogen to fuel stem growth. Blueberry flower buds develop along growing stems, with flowers open along those stems the following spring. More stem growth means more blueberries, to a point. For many years I have foregone soybean meal because the the plants were overly vigorous, creating a dense jungle that makes getting to the berries too difficult.

One other key to success and topnotch flavor is a net during the summer to fend off birds and — for best flavor — careful picking of only dead ripe fruits.

Water, Too Much or Too Little

So far, the growing season here in the Northeast has been one with both dry spells and wet spells, more than usual of each. Some recent thunderstorms fool many a gardener into thinking that the soil has been thoroughly wetted. But such rains are often only a drop in the bucket.

The only way to know for sure if enough rain has fallen for plants to really slurp up water is to check the soil or measure the actual amount of rainfall. A friend tells me he waters his plants every day. Every day! How much? It could be too much or too little, and probably is one or the other. I like to quantitate things so I measure rainfall or watering, as well as soil moisture, in a few different ways.

First, measuring water added to the soil: The ideal is about a 1 inch depth of water per week, which is equivalent to about a half a gallon per square foot of surface area. For hand watering a young tree, with an estimated root spread of only a couple of square feet, I fill the watering can with a gallon of water and sprinkle it on.
Rain gauge
Rainfall, or the water from a sprinkler, could be measured with a straight-sided container. I use a rain gauge whose tapered body can break down the measurement into tenths of an inch, readable from indoors.

Digital moisture probe.

Digital moisture probe.

I usually measure the actual moisture in the soil with a handy little meter attached to a probe that slides a half a foot down into the soil. As expected, the meter told me today that the soil is very wet. Not surprising after 3 inches of rainfall, as measure in the rain gauge, two nights ago. 

(There’s more about blueberries and water in my books Grow Fruit Naturally and The Ever Curious Gardener.)

PERMACULTURE(?) HERE ON THE FARMDEN

True Accusation?

Accusations of my being a permaculturalist, that is, a practitioner of permaculture, are true, but only partially so. Yes, I grow peppers in a flower garden and persimmon as much for its beauty (see Landscaping with Fruit) as for its delicious fruits, also integrating other edibles right into the landscape. And, like permaculturalists, I do try to maximize use of the 3-dimensional space in my farmden with, for example, shade-loving black currants growing beneath my pawpaw trees.
Farmden, aerial view
I am also a permaculturalistic in maintaining the integrity of my soil by not tilling it or otherwise disrupting the structure that builds up naturally in undisturbed soils. New ground is prepared for planting by merely smothering existing mowed or stomped down vegetation. I mulch with compost, leaves, wood chips and other organic materials to keep bare ground from ever showing. 
Sammy also likes the mulch
And like permaculturalists, I try to grow plants adapted to the setting so as to minimize pest problems. And poultry — ducks here on the farmden — wander freely, except in the vegetable gardens, to minimize pest problems, to provide fresh eggs, to add to the bucolic atmosphere, and to provide entertainment. And, in the shade of a Norway spruce, a rack holds up oak logs from which pop out shiitake mushrooms. I could go on.
Ducks

Why I Am Not a Full-Fledged Permy

Despite the assertion of one young, self-described “expert” permaculturalist, I am not a permaculturalist. I tend a permaculturesque farmden. Why the “-esque”? Because I part with true permaculturalists in a few critical ways.

Let’s begin with soil preparation. I smother existing vegetation beneath a few, typically four, sheets of newspaper topped with compost or some other weed-free, organic mulch. (I describe my methods in more detail in my book Weedless Gardening.) Many, perhaps most or all, permaculturalists prefer using corrugated cardboard from boxes as that first layer. The longevity of that cardboard on the ground is seen as an asset over paper. But I use paper so that soon after existing vegetation is smothered, the mulch and the soil below can begin to meld together. I don’t want any barrier to water and nutrients, or bacteria, fungi, earthworms, and myriad other soil organisms in place any longer than necessary. 
Beginning a garden
I part ways with permaculturalists by growing my vegetables rectilinearly, in straight rows within rectangular 3-foot-wide beds. Yes, the idea of organically shaped beds and keyhole gardens is very appealing –- on paper. But time, my time, is also an important element in the garden, and it takes a lot longer to maintain curved and somewhat randomly shaped bed than it does rectilinear beds.
Vegetable garden
And then there’s the permy way of tucking, say lettuce plants, beneath fruiting shrubs and trees. But I eat a lot of vegetables and there’s nothing like straight rows running down straight beds for packing a lot of vegetables into a given area, and making planting, weeding, and harvesting quicker and easier. When I go out to pick some vegetables for a meal, I don’t want to be remembering where I tucked the lettuce and wending my way through trees and then crawling beneath some shrub to get at it. 

Bed of lettuce and chinese cabbage

Permaculture originated and thrives in the dry climates of Australia and our Southwest. Over much of the country, and especially here in the Northeast, rainfall coaxes very exuberant growth from crop plants and weeds alike. Too many permaculturalists are liable to spend their first few permaculture years admiring their efficient and attractive use of space, and all the years hence cursing all the time needed cutting and weeding needed to keep growth of various plants in balance. What I need are some straight lines and a little elbow room.

(I have been hired more than once as a consultant on a property designed and planted by a true permaculturalist. I’m sure it looked great on paper and for the first few years, until it became a tangled mass of plants, more than most people could handle long term. Sometimes, the best course moving forward is to remove everything for a fresh, perhaps permaculturalesque start this time around. As one landowner told me, “a few years back I was ‘permacultured’ by some fine folks. I have been fighting my way back ever since.”)

“Forest gardening,” growing and eating from your planted forest, is receiving growing interest within permaculture circles. As you might guess, I’m also not a forest gardener, despite the fact that I have integrated fruiting trees, which do come from forests somewhere, as well as chestnuts, English walnuts, black walnuts, and other nutty things into my landscape.

Planted "forest"

Planted “forest”

I do have a miniforest in a portion of my meadow. The cool shade beneath the now large buartnut, shellbark hickory, maple, and river birch trees is not planted with herbs and vegetables for nibbling. It’s mostly a leafy mulch that fall in autumn, as in any forest floor. Oh, with a bow to forest gardening, I also planted ramps there.

I plant fruits, vegetables, and nuts to provide sustenance, not just a nibble here and there. 

I Aim for Good Food, Not a Concept

I’m growing my own fruits and vegetables because I want great-tasting food. It seems to me that permaculture is usually about making growing plants easier. Nothing wrong with that, of course, except sometimes plants that are easiest to grow aren’t those that have the best flavor. I grow elderberries (back in my more hard-core permaculture planting along with aronia, rosa rugosa, seaberry, and highbush cranberry). Could anybody claim that a fresh picked elderberry can hold a candle to, flavorwise, a fresh picked blueberry?

Elderberry harvest

Elderberry harvest

Speaking of blueberry, they are easy to grow. But, if you want best production of flavorful berries, best to put some effort into getting the soil right, pruning correctly and annually, and netting to fend off birds so you can harvest truly ripe berries. Grapes? They need abundant sunlight, not the shady but easily supplied support of a nearby tree, for best quality and easy picking. Pruning is critical for topnotch flavor and pest control. It all takes effort, but is worth it.

Today's blueberry harvest

Today’s blueberry harvest

Although I am very intimate and knowledgeable about the plants I grow, I am no expert on permaculture. Perhaps I have misconstrued certain permaculture techniques or am totally missing the concept (even though I was accused of being a permaculturalist). I welcome feedback.

GARDENING “HANDWORK”

To Haul or Not to Haul

Hauling manure hardly seems to make sense these days, considering that lugging 500 pounds of horse manure gives plants about the same amount of food as a 50 pound bag of 10-10-10. And the latter for only about ten bucks!

Human manure piles, China, 1900

Human manure piles, China, 1900

But whereas 10-10-10 supplies only food (and only three of the sixteen needed nutrients at that), manure has other benefits: it aerates the soil; it helps soil capture and cling to water; and it renders nutrients already in the soil more available to plants. Nutrients from synthetic fertilizers are used up or washed out of the soil by the end of a season, yet benefits from each application of manure last for years. Even ingredients of a concentrated organic fertilizer have little benefit as far as soil aeration and water retention are concerned.

Manure is a traditional way of feeding plants, to the extent that applying synthetic (chemical) fertilizers once was referred to as a form of “manuring,” and certain plants grown specifically to improve the soil are called “green manures.”

When we talk of manure, though, we really mean animal excrement plus bedding. The bedding itself –- usually hay, straw, or wood shavings -– is itself responsible for some of the benefits of manure. The amount of nourishment manure supplies to a plant the first season depends on the ratio of bedding to excrement. More bedding means less nourishment to plants the first season, but greater residual effect for subsequent seasons. Unfortunately, bedding also can be a source of weed seeds.

Mostly manure pile

Long ago my compost piles were mostly manure

“Hot manures” are so called because they readily heat up when stacked in a pile. The heat comes from the burst of microbial activity stimulated by these manures’ relatively high concentrations of nitrogen and low concentrations of water. Horse and poultry manures are “hot;” cow and pig manures are “cold.”

How to Handle It, Generally

Okay, so you have manure in hand, or rather in pitchfork (a five-tined pitchfork is my preference for manure handling). What next?

Most gardeners dig it into the soil immediately. If the manure is well rotted -– meaning bits of hay, etc. no longer are recognizable –- planting can proceed as soon as the soil is smoothed.

If the manure is relatively raw, wait at least 2 weeks for things to settle down, microbially speaking, before planting. Especially if this raw manure has a high proportion of bedding, a much longer wait is needed before planting. Microbial decomposition of that extra carbon-rich bedding requires nitrogen which, if in sufficient amounts are not in the associated manure, must come from soil reserves. Microbes are more adept at getting at that nitrogen than are plants, so plants are starved — at least until the extra carbon is digested (and the carbon/nitrogen ratio in the ground is about 20/1). One advantage to digging manure into the garden in autumn is that it avoids any delay in planting in spring.

Spreading manure on a farm

Spreading manure on a farm

In lieu of digging, just lay manure on top of the ground as mulch. This is fine if the manure is rotted, but nitrogen volatilizes from fresh manure exposed to sun and wind. The nitrogen loss is wasteful, but may be worth the sacrifice considering the benefits of the mulch. And the nitrogen starvation mentioned previously doesn’t occur because decomposition is very slow, at the interface of the mulch and the soil.

And More Specifically

Spreading compost on established bed

I have access to more horse manure than I could ever possibly want, and the way I usually handle the manure is to compost it before putting it on or in the soil. In a compost pile, manure is mixed with other ingredients (garden residues, vegetable scraps, leaves, soil, etc.), so the result is a better-balanced fertilizer. Also, the heat of composting kills most weed seeds present in either the excrement or the bedding.

The amount of manure to add to soil depends on whether the manure is rotted or fresh, and what kind of animal provided the manure. You can add too much manure to soil: I once had a chicken farming neighbor who killed his asparagus bed by blanketing it under 6 inches of chicken manure (very hot stuff!). Twenty-five to 50 pounds per hundred square feet is about the right amount.

(Manure is the only bulky, beneficial source of organic nitrogen. Some other sources are kitchen scraps, young plants, cultivated and wild — as in “weeds” —  and especially, legumes.)

  The word “manure” comes from the old French word manoevrer, meaning “to cultivate by hand” (in turn from the Latin words for “hand” and “work”). All this manure handling is a lot of physical work, but isn’t exercise another benefit of gardening?

Plant Sale in Progress (mostly fruits, many uncommon, and uncommonly delicious ones)

A reminder: my plant sale, online with live pickup, is in progress for another few days. To view the plant list, to order, to pay, and — VERY IMPORTANT — to schedule a pickup time (May 29-31 and June 2), go to https://leesannualplantsale.squarespace.com

MYCO-WHAT?

It’s Greek To Me (and You)

This far north, there’s only a little to do garden-wise this time of year, so let’s sit back and ponder the wonders of plant life. Mycorrhiza, to be specific. Wait! Don’t stop reading! Sure, the word “mycorrhiza” appears intimidating. But mycorrhiza are important in your garden, in the forest, to your trees and shrubs, maybe even to your houseplants.

First, the pronunciation. Say: my-ko-RY-za. It sounds nicer than it looks. 

Now let’s take the word apart to see what it means. “Myco” comes from the Greek word meaning “fungus” and “rhiza” from the word meaning “root.” Mycorrhiza, then, is a “fungus-root,” an association between a plant root and a fungus so intimate that the pair has been given a name as if it was a single organism.

Mycorrhizal blueberry root

Mycorrhizal blueberry root

Win-Win

The association is symbiotic, beneficial to both parties. One end of the fungus infects a plant root, while the rest of the long, threadlike body of the fungus ramifies through the soil. Nutrients are absorbed from the soil by those fine fungal threads and pumped back to the plant. The result: mycorrhizal plants can draw nutrients and water from a greater volume of soil than can non-mycorrhizal plants, and plant nutrition is improved. To cite one practical demonstration of this benefit, agricultural scientists in California found that the presence of mycorrhiza was equivalent to the addition of more than one hundred pounds of phosphorus fertilizer per acre on citrus trees.

Another kind of mycorrhiza, in apple root

Another kind of mycorrhiza, in apple root

The mycorrhizal association might be termed a balanced parasitism; the fungus does exact payment for its services. Carbohydrates are, literally, the fuel of life, and though mycorrhizal fungi are adept at drawing minerals from the soil, they can’t make their own carbohydrates. So these fungi draw carbohydrates from their host plants, who can make it. Sunlight fuels the photosynthetic reaction of carbon dioxide and water into carbohydrates and oxygen.

Not all fungi are mycorrhizal. Non-mycorrhizal fungi get their carbohydrates either by eating living things without returning the favor, in which case they are called parasites. Others eat once-living organisms such as wood, leaves, and dead animals, in which case the fungi are called saprophytes. Some fungi feed on either or both the living and the dead.

Myco-where?

Mycorrhiza are almost ubiquitous on the earth. Walk through the woods in spring or fall and most of the mushrooms you see on the forest floor are the reproductive structures of mycorrhizal fungi, periodically popping up through the ground to spread spores. Below ground, these mushrooms are connected to nearby tree roots by fine fungal threads.

The plant known as Indian Pipes (Monotropa uniflora) offers an eerie signal of the presence of mycorrhizae below ground. This plant, with one nodding flower, is thoroughly white, lacking any chlorophyll with which it could use sunlight to fuel its growth. Instead, its roots tap into a specific mycorrhizal fungus whose underground threads are also tapped into the roots of a nearby tree. Indian pipes is a parasite; it takes from the fungus and the tree, offering nothing in return.

Indian pipes

Indian pipes

Mushrooms are formed only by certain types of mycorrhizal fungi. Most mycorrhizal fungi are not so obvious, working unobtrusively in association with the roots of the vegetables and flowers in your garden, your lawn, shrubs, and trees. The gourmet’s truffle is the underground reproductive structure of one type of mycorrhizal fungus.

Most plants on our planet are infected with mycorrhizal fungi. Mycorrhiza are absent only in special situations such as in the acidic, nutrient-poor spoils left from mining operations, in agricultural soils that have been sterilized to kill pests, and in sterilized potting soil in flower pots. Certain plants never become infected; cabbage, spinach, buckwheat, and their relatives, for example.

The Practical Side

The importance of mycorrhiza is not diminished by their ubiquity. Mycorrhiza is a general term, and not all mycorrhiza are equal. A plant may be mycorrhizal, but perhaps not with the most effective species of mycorrhizal fungus or, perhaps, not enough of them. Mulching, fertilization, irrigation, chemical use and other gardening and agricultural practices alter the types and amounts of mycorrhizal fungi in the soil. Rototilling or turning over the ground, as you might imagine, disrupts those fungal threads. Except for high fertility, what’s good for plants — plenty of soil organic matter, growing plants, good aeration, adequate moisture — is also generally good for mycorrhizae.

Old-time gardeners would throw a handful of soil from an old apple tree into the planting hole for a new apple tree. A crude form of mycorrhizal inoculation? Agricultural researchers have tried to quantify why plants respond to inoculation with mycorrhizal fungi at one site, and not another. Which are the best fungi? What affects them? Recent research has shown that improved nutrition is only the most obvious effect of mycorrhiza. The mycorrhizal association also influences plant response to stresses such as drought, insects, and diseases.

As you might imagine, mycorrhizal fungi have been commercialized, available as inoculants or premixed into packaged potting soils. Under certain conditions, this might be beneficial. In many situations, it’s like “taking coals to Newcastle.” Usually, create conditions conducive to mycorrhizal formation, and a beneficial symbiosis will develop.

For my research as a graduate student, I studied the effect of, among other things, mycorrhizae in blueberry soils. Even my plants grown in sterilized soils in a greenhouse became mycorrhizal, which, while messing up that aspect of my experiment, did highlight how ubiquitous the association can be without the human hand.

If you want to lend your hand to the mycorrhizal association, you could actually extract and grow your own mycorrhizal inoculum. Read how, and learn all about mycorrhizae in Jeff Lowenfels’ excellent book Teaming with Fungi: The Organic Grower’s Guide to Mycorrhizae.

At any rate, mycorrhiza is a fascinating demonstration of ecology, the interrelationship of organisms on the earth.
Teaming with Fungi, cover

SNOW’S COME AND SO HAS FRUIT

Free and Attractive Mulch

  Beautiful. Floating down from the sky. A white blanket of “poor man’s manure.” That’s what gardeners and farmers have called snow.
Garden under snow
In fact, snow does take some nitrogen from the air and bring it down to ground level for plant use in spring. Not that much, though. Just a few shovelfuls of real manure could supply the same amount of nitrogen as a blanket of snow.

  Mostly, what I like about the 15 inch deep fluffy whiteness now on the ground is the way it insulates what’s beneath it. Fluctuating winter temperatures wreak havoc on plants, coaxing them awake and asleep and awake and asleep as air temperatures go up and down and up and down. Each time plants are awakened, they become more susceptible to subsequent cold, the whole problem exacerbated with borderline hardy plants.

Anticipating cold weather and snow, last fall I cut back a cardoon plant and two artichoke plants, covered each with a large, upturned plastic planter, and then smothered everything in autumn leaves. Cardoon and artichoke, in fall with leafy coverBoth kinds of plants are probably cold-hardy to about zero degrees Fahrenheit, but here winter temperatures, except last winter, typically drop to about minus 20 decrees Fahrenheit. That snowy blanket provides extra protection that the plants might need — especially after last Saturday’s unseasonal low of minus 8 degrees.Cardoon and artichoke, snow covered

  Hardy orange (Citrus trifoliata) is another plant to benefit from snow cover. It’s a Citrus that’s allegedly cold-hardy into zone 5 (-20°F minimum temperature). I planted some seeds outdoors a few years ago and, while their roots survive winter cold, the tops die back to resprout each spring. I also planted out a more mature hardy orange that was given to me; it also suffered some cold damage.

The deeper this winter’s snow and the longer it stays deep, the more of the hardy oranges’ stems will survive till spring. Perhaps, helped along with global warming, enough of the above ground parts of the plants will survive to reward me one year with sweet-smelling blossoms and, less appealing, their very puckery fruits.

Multiplying Currants and Grapes

  Last fall, I cut stems from my black currants and grapes into 8 inch lengths. In the bare ground between some dwarf apple trees, I scratched some lines and pushed a straight-bladed shovel into the ground on that line. Levering the handle of the shovel opened up just enough space in which to shove one or two of those cut stems, distal ends up, right up to their topmost buds. Then I moved along the scratched line, pushed the shovel in again, shoved in more stems, and so on down each line. If all goes well, each of those stems will grow into a good sized plant that I can dig up and transplant next autumn.
Rooted currant cuttings
  That is, unless alternating freezing and thawing of the soil heaves those stems up and out of the ground. I’ve seen it happen, leaving a row of carefully inserted stems sitting on top of the ground by winter’s end.

  All of which is another reason I’m thankful for the snow. In addition to protecting plants from cold, the blanket modulates soil temperatures, keeping cold soil cold, which is how I’d like it to remain until spring. I could have — should have — thrown some fluffy, organic mulch, such as leaves or straw, over the stems to do the same thing. But I didn’t. I hope the snow stays.

Where One Plus One Does Not Equal Two, Figuratively Speaking

The harvest has begun: I picked the first fruit of the season this week. Not only that, but it was the first fruit I harvested from the particular plant. The fruit was a Sunquat, planted in a pot a year and a half ago. It summers outdoors and winters indoors, basking in sunlight streaming through a south-facing window.
Sunquat
Not many people have heard of Sunquats. I hadn’t. Citrus plants hybridize freely and Sunquat is one of many citrus hybrids, this one a mating of kumquat (Citrus japonica) and Meyer lemon. I happen to be a big fan of the tart flesh and spicy, sweet skins of kumquat fruits. I also happen to be a big fan of Meyer lemon, which is not a true lemon but is probably a hybrid of lemon and sweet orange.

Meyer lemons are juicy and somewhat sweet, with a flowery aroma. They also bear prolifically. As testimonial to their precocity, I once had a cutting that flowered soon after rooting, when it was only a few inches tall.
Meyer lemon cuttings rooted

  So what could be bad about combining kumquat and Meyer lemon? A Sunquat! The skin was sour without picking up any of the spicy tang of a kumquat’s skin. The flesh was much less puckery than kumquat or lemon, but was uninteresting, just bland. Perhaps harvesting a bit underripe, before the skins turn full yellow, will put some pizazz in a Sunquat.

If not, I’ll stick to growing Meyer lemons and kumquats, each on their own and with their own delectable flavor.
Meiwa kumquat plant

COMPOSTING, A DIDACTIC & A PERSONAL VIEW

Start With The Carbs

A bit of chemistry might be good for your compost. Just a bit. Actually, we mostly need to deal with only two familiar elements of the 100 plus known ones. These two elements are carbon and nitrogen, and they are the ones for which the “bugs” that do the work of making compost are most hungry.

“Work” is too strong a word, though, because these composting bugs do nothing more than eat. Nonetheless, a balanced diet — one balanced mostly with respect to carbon and nitrogen — does these bugs, the composting microorganisms, good.

This time of year, the microorganisms’ smorgasbord is set with an especially wide array and abundance of carbon-rich foods. You can identify these foods because they are old plants or plant parts. As such, they are mostly brown and mostly dry. Autumn leaves, for example. Other carbon-rich foods include wood chips, straw, sawdust, hay, and even paper, made — after all — from wood pulp or other old, dry plant material.
Haystacks and compost piles

By far the bulk of high carbon — carbohydrate — foods for my compost organisms this time of year is hay that I scythe from odd corners here and there in my meadow. (Most of the meadow gets mowed by tractor once a year.) The hay is a mix of a wide variety of plants, mostly various species of grasses and goldenrods, but also, depending on where I cut, loosestrife, asters, New York ironweed, Joe Pye weed, and others. That varied mix is good for a compost pile; those microorganisms, like us, thrive on a varied diet which provides a slew of macro- and micronutrients which then end up in the finished compost and then my vegetables.

Next, Some Proteins

Just as we humans cannot live on bread and pasta alone (carbon-rich foods), so it is with composting microorganisms. So let’s now peruse the smorgasbord for some nitrogen-rich fare. This would include green stuff: young, succulent plants and plant parts. There’s not a whole lot of this stuff around this time of year, but there is some, including grass clippings, kitchen scraps, and microbial fare such as old, spent tomato, broccoli, pepper and other garden plants.

My scythed hay also provides some nitrogen-rich food — early in the season when its lush and green and only a foot or two high. But it has to be used in moderation because there’s not a whole lot of carbon-rich foods early in the season. Except that is, for the previous autumn’s fallen leaves and arborist wood chips that I stockpile. I also make some haystacks to save late-season hay for use in winter and early in the growing season.

Meadow with cartful of scythed hay

Early season scythings

When there’s insufficient nitrogen foods to balance out all the carbon foods you could now find for your compost, it’s time for dietary supplements. Nitrogen-rich supplements for the compost pile include manures and nitrogen fertilizers. Manures usually also add some carbon food, in the form of the straw, wood shavings, or whatever else the animal was bedded in.

No need to get out the chemistry set to analyze how rich a food is in carbon or nitrogen so that you can get them in exact balance (which, if you must know, is a ratio of 20:1). Just keep in mind that the younger the plant part, the richer it is in nitrogen. Also that rabbit manure is richer in nitrogen than is chicken manure, which is richer than, going down the line, sheep, horse, duck, cow, and, finally, pig manure. Nitrogen fertilizers are very concentrated sources of nitrogen.

If I need to supplement the compost diet with extra nitrogen, from fertilizer, I use something that acts organically in the soil, such as soybean meal, which is readily available from feed stores. Its nitrogen is released as various microorganisms feed on it.

Pile It In, and Monitor

So pile anything and everything that was once or is living into your compost bin, balancing carbon-rich foods with nitrogen-rich ones. After garden and backyard cleanup is finished for the season, the scale tips the other way as vegetable scraps become the most significant additions to your compost pile. Balance the food value of this nitrogen-rich material with an occasional cover of wood chips or hay from a pile you keep handy next to your compost bin.

The most important thing in making compost is a good bin. A “good” bin will keep scavengers at bay, be a barrier to weed seeds that might waft into the finished compost, is convenient to fill and empty, and maintains moisture and warmth within. It also keeps everything neat, looking like a compost pile rather than a garbage pile.

If you want to see how you’re doing as a compost “bug” dietician, monitor the goings on within your pile with a long-probed thermometer and your nose. If the materials are moist and outdoor temperatures not frigid, the well-fed pile will be decidedly warm — 120 degrees F., or more. Lack of heat reflects an excess of carbon-rich foods or insufficient water; odors are the result of excess nitrogen or too much water.
Compost thermometer

I take care of my pile’s water needs in two ways. First, when I build the pile I add materials of various texture so that the mix drains well — but not too well so that it can’t cling to sufficient moisture. A lot of water is needed to really wet the innards of pile. Add a lot of material to a compost pile at one sitting and you’d have to stand there, hose in hand, for a long time to really wet it. I’m not that patient, so the second way I take care of the pile’s watering needs is to hook up a small, static sprinkler to a hose along with a valve for adjusting the width of the spray to only cover the top of the pile. About 20 minutes of watering does the trick. (I periodically check moisture deep within the pile with a long-probed moisture meter.)

Keeping records of what you add to your compost pile and how it responds helps you remember what you did right and wrong. But “wrong” is too strong a word, because the material you put in your compost bin

Compost happens bumper sticker

will always turn to compost. As my bumper sticker reads, “COMPOST HAPPENS,” even if the process takes longer or becomes “aromatic” along the way.

For me, making and spreading compost is as rewarding and enjoyable as is gardening per se.

(For more about making compost, using it most effectively, and buying compost, see my book Weedless Gardening.)
Composted garden beds, S garden

READY FOR 2021

Why Now?

For the past week or so I’ve been getting parts of the garden ready for next year. Too soon, you say? No, says I.

Pole beans

Pole beans

A bed of corn and a bed of bush beans are finished for the season. Not that that’s the end of either vegetable. I planted four beds of corn, each two weeks after the previous, and the two remaining beds will be providing ears of fresh Golden Bantam — a hundred year old variety with rich, corny flavor — well into September.

The bed of bush beans will be superseded by a bed of pole beans, planted at the same time. Bush beans start bearing early but peter out after a couple of harvests. Pole beans are slower to get going, but once they do, they keep up a quickening pace until slowed, then stopped, by cold weather.

Why, you may ask, ready those beds now for eight months hence? One reason is that the garden is always such a flurry of activity in spring that I welcome one less thing that needs doing then. Also, part of garden preparation is thorough weeding (which I also keep up with, though less thoroughly, all season long). Any weeds checked now means less weed seed to spread around the garden and, in the case of perennial weeds, less opportunity to gain a foothold.

Bed of lettuce and chinese cabbage

And later in the season…

Planted bed, endive, lettuce

And, later in the season

And beds prepared now need not sit idle till spring. Right after getting the old bean bed ready for spring, I’ll plant it with vegetables that thrive in the cool weather of fall, vegetables such as lettuce, endive, turnips, Chinese cabbage, and winter radishes. The bed will be ready as soon as fall vegetables are harvested and out of the way.

And How? Simple.

No magic potions or secret techniques ready my beds now for next year. What’s needed, besides weeding and fertilizing, is to maintain or increase levels of soil organic matter. Organic matter is integral to good fertility, maintaining a diverse population of beneficial soil microbes, and improving soil aeration and moisture retention. It’s what put the “organic” into organic gardening.

The way I provide all this can be summed up in one word: compost.

Okay, there is more to it. My vegetable garden is laid out in beds that are 3 feet wide with 18 inch wide paths between them (and a 5 foot wide path up the middle of the garden for rolling in cartfuls of compost). Soil in the beds has not been tilled or otherwise unduly disturbed for decades, which has many benefits that I delve into in my book Weedless Gardening.

First step in getting the garden ready for next year is to remove all existing plants, be they corn, bean, or weed plants. I excise most plants, including weeds, by grabbing each near its base and giving it a slight twist to sever it from its fine roots, which are left in place. Coaxing with my Hori-Hori knife is sometimes needed. Corn plants definitely need coaxing, which I do by digging straight down around the base of each plant and then giving it a yank. After all this, I smooth out the ground, if necessary, with the tines of a rake or pitchfork.

A one inch depth of finished compost should provide all that intensively grown vegetables require for a whole season. That one inch of compost is laid down like a rich icing right on top of the bed. Finished!
Composted garden bed
Okay, there’s sometimes a little more to it. I noticed weak growth in one of the later corn beds, possibly due to nitrogen deficiency, although untimely, temporary malfunction of my drip irrigation system at a critical growth stage for the corn is another possibility. Just too make sure, I will sprinkle some organic nitrogen fertilizer (soybean meal) in that bed when I prepare it.

(I could test the soil for some other nutrient deficiency, but after years of using compost made from diverse feedstuffs, some other nutrient deficiency is doubtful. There’s no good test for nitrogen because of its evanescence in the soil.)

Okay, there’s sometimes even a little more to my soil prep. If a bed is finished for the season and I have enough cleared beds for all the cool season vegetables, I could just prepare the bed, as above, and that would be the end of the story. But I don’t like to look at bare ground, so beds cleared and prepared early enough in the season, which is about the end of September here in Zone 5, get planted with a cover crop. Cover crops protect soil from wind and water erosion, latch onto nutrients that would otherwise leach down and out of the ground, and crumble the soil to a fine tilth with their roots. And going into winter, I’d rather look at a lush, green cover crop than bare ground.

Cover crop in autumn

Cover crop in autumn

My usual cover crop of choice is oats or barley. Both thrive in autumn’s cool, moist weather. They mesh well with no-till because they winterkill here in Zone 5.

This year, especially for my beds of corn, which is a nitrogen-hungry plant, I’ll mix crimson clover in with the oats or barley. As a legume, the clover will enrich the ground with extra nitrogen that it extracts from the air. And the vivid crimson flower heads, sitting atop stalks like lolliopops, will look nice.
Crimson clover

OF COMPOST, MICROWAVES, AND BLUEBERRIES

Manure Unnecessary

Manure or not, it’s compost time. I like to make enough compost through summer so that it can get cooking before autumn’s cold weather sets in. Come spring, I give the pile one turn and by the midsummer the black gold is ready to slather onto vegetable beds or beneath choice trees and shrubs.

I haven’t gotten around to getting some manure for awhile so I just went ahead this morning and started building a new pile without manure. It’s true: You do not need manure to make compost. Any pile of organic materials will decompose into compost given enough time.
Compost bins
My piles are a little more deliberate than mere heaps of organic materials. For one thing, everything goes into square bins each about 4′ on a side and built up, along with the materials within, Lincoln-log style from notched 1 x 6 manufactured wood decking. Another nice feature of this system is that the compost is easy to pitchfork out of the pile as sidewalls are removed with the lowering compost.

My main compost ingredient is hay that I scythe from an adjoining field. As this material is layered and watered into the bin it also gets sprinkled regularly with some soil and limestone. Soil adds some bulk to the finished material. The limestone adds alkalinity to offset the naturally increasing acidity of many soils here in the Northeast. Into the pile also goes any and all garden and kitchen refuse whenever available.
Hay for composting
What manure adds to a compost pile is bedding, usually straw or wood shavings, and what comes out of the rear end of the animal. The latter is useful for providing nitrogen to balance out the high carbon content of older plant material in the compost, such as my hay.

But manure isn’t the only possible source of nitrogen. Young, green, lush plants are also high in nitrogen, as are kitchen trimmings, hair, and feathers. Soybean meal, or some other seed meal, is another convenient source.

Compost piles fed mostly kitchen trimmings or young plants benefit from high carbon materials. Otherwise, these piles become too aromatic, not positively.

As I wrote above, “Any pile of organic materials will decompose into compost given enough time.” Nitrogen speeds up decomposition of high carbon compost piles, enough to shoot temperatures in the innards of the pile to 150° or higher. All that heat isn’t absolutely necessary but does kill off most pests, including weed seeds, quicker than slow cooking compost piles.Smelling compost

Plus, it’s fun nurturing my compost pets, the microorganisms that enjoy life within a compost pile.

Novel Use for Microwave

I bought my first (and only) microwave oven a few years ago ($25 on craigslist) and have cooked up many batches of soil in it. You thought I was going to use it to cook food? Nah.

Usually, I don’t cook my potting soils, which I make by mixing equal parts sifted compost, garden soil, peat moss, and perlite, with a little soybean meal for some extra nitrogen. I avoid disease problems, such as damping off of seedlings, with careful watering and good light and air circulation rather than by sterilizing my potting soils.

Peat, perlite, soil, and compost

Peat, perlite, soil, and compost

Recently, however, too many weeds have been sprouting in my potting soil. Because my compost generally gets hot enough to snuff out weed seeds and because peat and perlite are naturally weed-free, these ingredients aren’t causing the problem. Garden soil in the mix is the major source of weeds.

So I cook up batches of garden soil, using the hi setting of the microwave oven for 20 minutes. My goal is to get the temperature up to about 180 degrees F., which does NOT sterilize the soil, but does pasteurize it. Overheating soil leads to release of ammonia and manganese, either of which can be toxic to plants. Sterilizing it also would leave a clean slate on which any microorganism, good or bad, could have a field day. Pasteurizing the soil, rather than sterilizing it, leaves some good guys around to fend off nefarious invaders.

After the soil cools, I add it to the other ingredients, mix everything up thoroughly, and shake and rub it through ½ inch hardware cloth mounted in a frame of two-by-fours. This mix provides a good home for the roots of all my plants, everything from my lettuce seedlings to large potted fig trees.

Blueberry Webinar

Blueberries, as usual, are bearing heavily this year, with over 60 quarts already  in the freezer and almost half that amount in our bellies. After years of growing this native fruit, it has never failed me, despite some seasons of too little rain, some of too much rain, late frost, or other traumas suffered by fruit crops generally.

All of which leads up to my invitation to you to come (virtually) to my upcoming Blueberry Workshop webinar. This webinar will cover everything from choosing plants to planting to the two important keys to success with blueberries, pests, harvest, and preservation. And, of course, there will be opportunity for questions. For more and updated information, keep and eye on www.leereich.com/workshops, the “workshops” page of my website.
Bunch of blueberries