COMPOST TEA: SNAKE OIL OR PLANT ELIXIR?

Is the Jury Still Out on Compost Tea?

    In gardening, as in life, you can’t help but want to love some things, compost tea being one of them. After all, compost is good, tea is soothing, so what’s not to love about compost tea?
    Perhaps it depends on how you brew your tea. Traditional compost tea was and is made by hanging a burlap bag of compost in water, then diluting and drenching the ground or the potting mix of a potted plant with the nutritious, coffee-brown liquid.
    More recently, “aerated compost tea” (ACT) has soothed gardeners from coast to coast, the result mostly of the promotional efforts of soil scientist Dr. Elaine Ingham. This tea is brewed similarly to the traditional tea, except that extra foods, such as molasses (honey would seem more in keeping with the tea theme), brewers yeast, and bran, are also added, and — most important — the tea is aerated throughout the brewing process.

Brewing up a batch for some plants.

Brewing up a batch for some plants.

    The soothing effect from ACT is not nutritional, but biological. You spray the tea on leaves or soil to spread beneficial microorganisms leached from the compost whose populations were beefed up by all that aeration and added nutrients. These happy microbes fight off attack by pathogens and insects, perhaps by making the offenders sick or unable to reproduce, perhaps by making the plants more healthy, or any one of a number of other hypothesized manners.
    Coming from their home in the dark, moist, nutrient-rich innards of a compost pile, could these friendly microbes really be expected to survive on the bright, dry, nutrient-poor surface of a leaf? And evolutionarily-speaking, when would Mother Nature ever have made provisions for compost, let alone compost tea, let alone ACT microbes, to colonize a leaf and do good there? But this is all speculation; surely someone must have tested whether or not compost tea is really “soothing”  to plant life.

How to Really Test Effectiveness

    A slew of gardeners and farmers have tried ACT and can attest to its benefits. Matter of fact, a whole industry is dedicated to testing composts and compost teas, even selling compost tea brewers and compost tea itself.
    The way to truly ascertain the efficacy of compost tea is to subject it to the same scientific scrutiny as you would anything else: Come up with a hypothesis (such as “Compost tea prevents powdery mildew of squash plants”) and then design an experiment to test the hypothesis. Said experiment would need both treated (compost tea sprayed) and control (water sprayed) plants. Most gardeners and farmers go to the trouble of spraying compost tea because they believe it will be effective, so are not willing to leave a portion of untreated (control) plants. Their endorsements, then, must be taken with a grain of salt, and the same must be said for endorsements from anyone reaping financial gain from compost tea.
    One treated and one control plant, even one treated and one control plot of plants, would not be sufficient for a good test. Biological systems are complex. Grow 10 tomato plants under exactly the same conditions and some will grow a little more, some a little less than the others. With too few test plants, natural variations in plant growth might overwhelm variation due to a treatment. With enough plants to even out and offer a measure of natural variations in, say, plant growth, effects of a treatment are better parsed out.
    And finally, randomization is needed to even out any effects of, say, location. Perhaps one side of a plot is more windy, or the soil is slightly different, or there’s a bit more sunlight. Rather than have all the treated plants cozied together growing better or worse because of this added effect, even out these effects by randomizing the location of treated and control plants.
    Now you’ve got an experiment. Using a few arithmetic formulas or, these days, a computer program, you plug in the numbers and come up with a probability of an effect of the treatment. In agriculture, a 90% or 95% probability is usually considered sufficient. You can then answer “yea” or “nay” to the hypothesized question, in this example, “Does compost tea prevent powdery mildew of squash plants?” with a 90% or 95% confidence level

Okay, I’ll Try It

    I have a friend who is a big proponent of compost tea. Finally, he convinced me to give it a try but only after I made him agree to supply me with a brewer, some compost, and explicit instructions, just to avoid his finding excuses for failure of the tea treatment.
    A red flag went up when he advised me not to use it in my vegetable garden because it was “too organic.” I ended up, on his suggestion, spraying a few strips down my lawn and parts of some bean rows on a friend’s farms.
    This admittedly nonscientific test conclusively showed no benefit at all from the tea.

Snake Oil, Mostly

    So what’s the scientific verdict on compost tea? The answer is not so simple, in part because it depends whether the reference is to traditional compost tea or ACT, the kind of plant, the compost ingredients, how long the tea is brewed, how often tea is applied, etc.
 

Spreading compost, letting rain make the "tea."

Spreading compost, letting rain make the “tea.”

   Good experiments have been performed, from which the following general conclusions can be made: 1) ACT  is not reliably beneficial (and often has a negative effect or spreads human pathogens such as Salmonella); 2) Traditional compost tea has been shown to be often but only mildly beneficial for root diseases; 3) If sufficiently, but not too, dilute, either ACT or traditional compost tea can supply nutrients to feed plants.
    My pea plants succumb early every summer to some root disease, possibly fusarium. I am tempted to drench the soil for the peas with traditional compost tea. Perhaps I’ll even set it up as a crude experiment, keeping in the back of my mind the admonition of Charles Dudley Warner (My summer in A Garden, 1871), “I have seen gardens which were all experiment, given over to every new thing, and which produced little or nothing to the owners, except the pleasure of expectation.”
    Mostly, though, I’ll continue to do what I’ve been doing, spreading compost on top of the ground and letting rainwater make the tea.

MANURE ABSOLVED, PRUNING STARTED

Horse Manure: Not Guilty, So On To Pruning

    A dark cloud no longer hangs over my horse manure, that is, the horse manure that I occasionally truck over here to add to my compost piles. I wrote a few weeks ago about the possibility of herbicide that, when applied to hay, retains its toxic effect when an animal eats the hay and even, for a long time, after that animal’s manure has been composted or spread on the ground.
    My herbicide residue concerns were soothed with a simple assay that showed satisfactory growth from bean seeds in both hay that was suspect and hay of known integrity. Also, the bedding in the horse manure is mostly wood shavings rather than hay.
    But another ugly dragon kept raising its head above the manure. Another chemical, this time, Ivermectin, a de-worming medication given to horses (and other animals). Ivermectin or its metabolites might pass through the animal and injure soil dwelling creatures such as beneficial nematodes and earthworms. Past studies have shown negative effects on, for example, “dung fauna and degradation of faeces” (to quote a research paper from 2006).
    Ivermectin is, admittedly, a very useful material, even useful in humans to combat lice, bedbugs, and some more frightening tropical afflictions such as river blindness and elephantiasis. Agriculture is always a balancing act, but I like to keep my soil-dwelling partners happy.
    So I was gladdened when a veterinarian recently directed me to a Stanford University publication that summarized research findings on the environmental effects of Ivermectin. To whit: Ivermectin is excreted and it can affect earthworms, springtails, and other fauna. But it degrades quickly at summer temperatures (1-2 weeks, but much longer in winter) and within a day or two of exposure to bright sunlight. With temperatures within my compost bins reaching 150°F., or more, with the compost sitting many months before use, and with the compost being spread on top of the ground, little Ivermectin would end up in the soil. And soil anyway naturally has low levels of this compound.

Snow Makes Me Taller

    Let’s look aboveground, at stems; there’s pruning to be started. With well over a foot of snow on the ground, I turn my attention to taller plants. The snow is actually an advantage because, with snowshoes on, I can reach more than a foot higher into the branches without a ladder.

Sammy (the dog) and I pruning pawpaws

Sammy (the dog) and I pruning pawpaws

    For now, I’m going to start with the easiest pruning, mostly with plants that don’t need regular pruning beyond removing dead, diseased, broken, and grossly misplaced branches. Right here, such plants include pawpaws, plums, cornelian cherries, and a teenage honeylocust tree. Light is important for fruit production from the fruit trees and, generally, to keep diseases and insects at bay, so I also prune away enough branches to let remaining branches bathe in sunlight.
    I go at the pawpaws with one more goal in mind, to keep fruit from forming either too high in the tree or two far out on the limbs. Pawpaw trees will grow 15 to 25 feet high but I harvest fallen fruit from the ground. By my estimation, fruit can make a soft landing, undamaged, from a height of about 10 feet onto mulched ground. So I lop back the tops to weak side branches at about that height.
    Each pawpaw flower is a multiple ovary, potentially spawning up to nine fruits, each of which can weigh more than half a pound. That’s a lot of weight perched onto the end of a branch, so I shorten long branches to decrease leverage of that fruit load.
    (More about all types of pruning on all kinds of plants in my book, The Pruning Book.)

A Beautiful Climber

    I actually did begin pruning a few weeks ago, before the first snow fall. The plant was hydrangea — no, not the common bigleaf hydrangea which has many people scratching their heads about how to prune, but climbing hydrangea (Hydrangea anomala subsp. petiolaris).
 

Climbing hydrangea in summer

Climbing hydrangea in summer

   Climbing hydrangea is one of the most beautiful vines, even right now as the peeling, pale cinnamon, bark is in focus among the leafless stems. All summer long, the stems are clothed in lustrous green foliage and, in early, summer clusters of white flowers twinkle against that backdrop like stars in the dark sky.
    As expected, the vine took a few years to get firmly established. Now it threatens to engulf my brick home except that I want to restrict it to only the north wall. Every year now, I prune back stems creeping like groping fingers around the east and west walls. And each year the flower stems reach further directly out from the wall, so I also shortened them.

Climbing hydrangea, partially pruned

Climbing hydrangea, partially pruned

    The present pruning doesn’t permanently subdue the plant. This summer, I’ll again shorten the wandering stems, and I’ll be back at it again next winter and for winters to come.

FIRST SOWINGS OF THE YEAR, DEADLINE MISSED

 Onions & More, Late But They’ll Be Fine

   I missed my deadline by four days, sowing onion seeds on February 5th rather than the planned February 1st. That date isn’t fixed in stone but the important thing is to plant onions early.
    Onions are photoperiod sensitive, that is, they respond to daylength (actually, night length, but researchers originally thought the response was to light rather than darkness, so the phrase “daylength sensitive” stuck). Once days get long enough, sometime in June, leaf formation comes screeching to a halt and the plants put their energies into making bulbs. The more leaves before that begins, the bigger the bulbs.
    Plants from seeds sown outdoors — towards the end of March — won’t have as many leaves as plants given a jump start indoors. I like big bulbs; hence the early February sowing.

Fresh Seeds & Mini-furrows in a Plastic Tub

    First step on my way to onion-dom is to get fresh seeds. Onion seeds are relatively short lived and I want to give the plants plenty of time to grow. I don’t risk delays from poor germination and replanting of old seed.Onion seeds being sown in mini-furrows in pan of potting soil.
    Seeds get sown in a miniature “field:” A plastic tub 18 inches by 12 inches, with drainage holes drilled in its bottom and filled 4 inches deep with potting soil. Some weed seeds are unavoidably lurking in the garden soil and compost in my homemade potting mix, so I top the potting mix with a one inch depth of a weed free, 1:1 mix of peat moss and perlite.
    The edge of a board pressed into the firmed soil mix in the tub makes furrows, 6 of them equally spaced and about 1/2 inch deep within the tub. Into each furrow go onion seeds, sprinkled at the rate of about 7 seeds per inch. Once the furrows are closed in over the seeds, I water thoroughly and, to avoid washing away seeds, gently.
    Covered with a clear pane of glass and warmed to 70 to 75° F, the seeds should appear as grassy sprouts above the soil mix within a couple of weeks. From then on, my goal is to keep the plants happy with abundant light and water as needed. They get a haircut, their leaves snipped down to 4 inches, whenever they get too floppy. The compost and alfalfa meal in the potting mix should provide sufficient nourishment to the seedlings until they are ready for the great outdoors. That deadline is April 15th, weather permitting.

Other Cool Temperature Seeds Join the Party

    Onions won’t be alone on the seedling bench in the greenhouse. I’m also now sowing seeds of celery, celeriac, and leek. All, like onion, need a long period of growth before they’re ready for outdoors.
 

Onion seedlings, up and growing.

Onion seedlings, up and growing.

   These seeds get sown in furrows in small seed flats from which the seedlings, once they have two leaves, are gingerly lifted and cozied into waiting holes poked into the potting mix filling seed trays with individual cells. Little growing space is needed because a single seed flat can be home to a few kinds of seeds and the celled trays in which the seedlings grow until planted outdoors can house about two dozen plants in a square foot.
    I’m sowing lettuce in a similar manner. In contrast to celery and company, lettuce grows quickly. It’s needed to fill in gaps opened up from winter harvests of kale, lettuce, mâche, claytonia, celery, and parsley in the greenhouse, and should be ready to eat in April.

Nature & Nurture & the Spiciness of Onions

    Last year’s onions were abundant, large, sweet, and juicy. Anticipating their not keeping well, we ate them quickly, pulling the last ones from their hanging braid in the basement sometime in November. These were so-called European-type onions, varieties such as Ailsa Craig and Sweet Spanish.
    Next year we should have fresh onions for soups and stews on into winter because I’m growing some American-types, New York Early and Copra. American-type onions are actually sweeter than European-type onions, but their sweetness is masked by their increased pungency. That pungency comes from sulfur compounds, which are vaporized during cooking. Those sulfur compounds are also what help these onions keep longer.

Stored onions, in basement

Stored onions, in basement

    Soil enters the picture when it comes to onion flavor and storability. Sulfur is an essential plant nutrient and the more sulfur in the soil, within limits, the more sulfur in the onions. Sulfur is a key component of organic matter, so my compost-rich soil (with a whopping 15% organic matter) should have plenty of sulfur.
    Still, I’m thinking about spreading sulfur, the same pelletized sulfur I use to maintain soil acidity beneath my blueberry bushes, on half my onion beds to see if flavor or storagability are noticeably affected.

HOW TO FEED THE WORLD

Perennial Wheat to Save Our Soil, But What About Compost?

    We — that is, almost all of humanity — get all our sustenance from the thin skin that covers out planet, the soil. In appreciation of this, the United Nations has declared 2015 “The Year of Soil.” “Soil is more important than oil,” stated Wes Jackson, founder of the Land Institute, in his keynote at this year’s recent NOFA-NY  conference. Like oil, soil is a nonrenewable, or only slowly renewable, resource. Centuries go by before rainfall, freezing, thawing, and microbes and plants eat away at rocks to make new soil; on average, it takes a thousand years for the creation of a mere half-inch of new soil.
    The problem is that, as with oil, we humans are using up soil faster than new soil is being created — 10 to 40 times faster! Also, as with oil, that soil, as it is used, releases carbon dioxide and other greenhouse gases. Tillage exposes carbon stored in the ground to air, burning” it up, and annual crops, which are represented by sweeping fields of corn, soybeans, wheat, and other staples of civilization, put little of the carbon that they take in from air below ground. Agriculture is the second highest generator of greenhouse gases.
    Whew, what to do? Dr. Jackson’s tack, for the past half century, has been to focus on shifting our staples from annual to perennial crops. Wheat, for instance. Kanza, a hybrid, perennial wheat under development at the Land Institute, would sequester carbon by not requiring annual tillage and by packing carbon compounds into its long-lived root system. Perennial crops also decrease opportunities for soil erosion (another source of soil loss), grow with less added fertilizer and water,  and have the potential to increase biodiversity for a healthier ecosystem.

Organic Materials: Wasted Fertilizer

    What about vegetables, how are they treating our resources? Up to the podium stepped Tim Crews, director of research at the Land Institute, to give the roomful of organic and aspiring organic vegetable farmers and gardeners bad news: Our soil care is not sustainable. All that manure hauled onto our fields or piled high into compost piles is bedded with hay or comes from animals that have been fed grain. The grain or hay was grown in fields that were fertilized, most of it with commercial fertilizer which is mostly made from atmospheric nitrogen via the Haber-Bosch process which requires — you guessed it — fossil fuel for energy.Organic materials feed compost pile.
    Still, the fact that organic farming and gardening wastes less energy than conventional farming and gardening should assuage some of the guilt that resonated through the room. The soil of a good organic farmer or gardener will, in general, be higher in organic matter (5.4% vs. 3.5%) and, hence, carbon. Said plot will require less water, less pesticide, and less manufactured nitrogen for fertilizer.

Compost, Garden — and Small Farm — “Gold”

    Compost, and compost alone, is how I maintain fertility in my vegetable beds. I do haul in some horse manure for that compost, and, as Dr. Crews pointed out, somewhere way back in that manure’s history, fossil fuel needed to be burned.
    But civilization, and especially industrialized civilizations, generate many waste products, of which horse manure is one. Picture also all the food waste from restaurants and supermarkets, autumn leaves and grass clippings that are considered “garbage,” even sewage effluent. All these organic materials contain carbon, some of which could be sequestered in the ground, to the benefit of agriculture and the environment, and some of which feed soil organisms and, in turn, plants.
 Turning compost pile.   Better to recycle as much of those organic materials as possible into agriculture than let them go to waste or cause pollution. The bottlenecks here are cultural and political rather than agricultural.

Grow Your Own Fertilizer

    Another way, as I suggested at the conference, to make vegetable farming more sustainable would be to grow your own carbon and fertilizer. A perennial grain or hay field could be harvested for the grain or hay for the animals or, even more efficiently, just for hay to use either as mulch or for composting. Running hay or grain through animals burns up carbon to grow and fuel the animal to the tune of, on average, about 6 times more needed in terms of calories. That is, for every 6 calories we grow and feed to a cow, we get only one calorie back when we eat the cow.
    Left to its own devices, any field will naturally build fertility. Bacteria, free-living bacteria and symbiotic with the roots of legumes, harvest atmospheric nitrogen and put it in the ground, and the combined action of myriad soil organisms slowly chew away at a soil’s rocky matrix to release other nutrients for plant use. Plants grow, their roots oozing substances that further stimulate microbial activity and soil fertility.

Nodules from nitrogen-fixing bacteria on soybean roots.

Nodules from nitrogen-fixing bacteria on soybean roots.

    The key word in the previous paragraph is “slowly.” In order to be able to harvest fertilizer in the form of hay from a field year after year, sufficient time must be allowed between harvests for fertility to be garnered from the air and rocks. For that you need either more land or less harvest. The big picture, then, is to have more land, to make better choices in how the land is used, to utilize organic practices, and have fewer people.
    With the problems of soil improvement, global warming, sustainability, and agricultural production solved, I’m going to sow onion seeds. Planted in flats in potting soil at 7 seeds per inch, I should have plenty of pencil-thick seedlings ready to poke into holes in compost enriched beds in early May.

LECTURES THIS WEEKEND

Feb. 14, 2015
Gardener’s Supply Co.,Burlington, VT
Espalier Fruits
My Weedless Garden

Feb. 15, 2015
Northeast Organic Farming Association of VT, Winter Conference,
Burlington, VT
“Hardy Kiwifruits”
“Compost Tea: Snake Oil or Plant Elixir?”

LUSTING FOR AVOCADOS, HOME GROWN, OF COURSE

A Long Journey to Avocado-dom

This far north, an avocado plant provides reliable entertainment and, less reliably, the makings of guacamole. The entertainment doesn’t compare with the excitement of a car chase on the silver screen; it’s slower but very engaging.

To whit: I’ve been watching roots on two avocado pits elongate and branch. I spend a lot of time with plants; here is my opportunity to spend quality time with their roots. That’s all possible because avocado pits, suspended in water, will sprout roots whose growth can be watched.  (Odd, since wet soils are the nemesis of avocado trees planted outdoors in tropical and subtropical climates, and you can’t get much wetter than water.)Avocado sprouting in water

Despite being plants of warm climates, avocados are frequently raised by us northerners, as houseplants. I could have planted the pits in potting soil in a pot, but would have missed out on root entertainment. So I stuck three toothpicks into and spaced evenly around each pit so that the pits could be suspended in a beaker with their bottoms — their fatter ends — sitting in water. Taking a thin slice off the top and bottom of the seed, which I did, reputedly speeds germination.

Roots typically sprout before the tops show any sign of growth. 

Whoops, Things Don’t Look So Good

Avocado houseplants are so common that probably none of the above is new information to most readers. I’m embarrassed, then, to admit that my two plants have faltered in their growth.

One of them sent a sprout upwards after its roots were a couple of inches long. That sprout has dried out and, of course, ceased growth.

I noticed a slime surrounding the root of the other pit. This pit was very slow to sprout, and my guess is that there’s some bacteria attacking the weak growth.

I ascribe both failures to growing conditions which, here, indoors, are a far cry from the mostly warm, humid climes avocados call home. Mine sit near a window, experiencing wide swings in temperature in a room heated with a wood stove. Starting new plants in spring should bring better luck.

Entertained by Apical Dominance

I did get to effect and observe apical dominance on one of the plants. More benign than it sounds, apical dominance is the tendency for most vigorous growth from a plant’s uppermost buds, those either at the ends of branches or spatially at the highest points.

Avocado, roots branchingThat vigor comes from suppression of buds lower down by auxin, a plant hormone that is produced in the uppermost buds and transported down the stem. Lopping off the top of a stem stops hormone production (temporarily, until the new higher buds start making it) so lower buds grow as they let go of their inhibitions. 

The taproot growing from one of the avocado pits was threatening to bump into the bottom of the beaker so I pinched off a half inch of its tip. The effect was a mirror image to what happens with branches: within a few days, branch roots began to develop. Very entertaining.

An avocado sprout typically shows strong apical dominance, developing into a gawky plant with a single, upright shoot. Cutting the growing top back by a few inches induces branching and makes for a prettier plant.

Flowers, But No Fruit

More than beauty, I’d like fruit from my avocado plant. Under good conditions, such as in the ground in Florida, a pit would need 8 years or more before it became old enough to bear fruit. And then, said fruit might not be of best quality because the seedling would reflect whatever jumbling around of chromosomes occurred when the female flower that gave rise to the fruit that begot the seed got dusted with pollen from a male flower.

Blossoms on my potted avocado

For quicker bearing and more reliable good taste, cloning is needed, in this case grafting a branch from a tree known to bear good-tasting fruits onto the young seedling. Bearing, then, occurs within 3 or 4 years, and the fruit should be identical to the mother plant from which the stem for grafting was taken.

Not so fast, though. You need two varieties for cross-pollination, and avocado has some pollination quirks. Still, my plan is to get new pits sprouting, and once their stems are large enough to graft, to get scions for grafting. Years ago, I did all this and got flowers but no fruit. I’m hopeful, this time around, to be making guacamole within 6 years.

Outside Now, For More Apical Dominance

The time is drawing near for some real gardening, which could start with pruning. I’ll be putting apical dominance to work on some young fruit trees — each a mere “whip,” single, vertical stem — planted last year. Shortening the main stem will induce side branches that will eventually become the permanent scaffold limbs of these plants. The more severely any stem is shortened, the fewer and the more enthusiastic the sprouts from the buds lower down.

GOOD BOOKS, GOOD LECTURES

One Book = Years of Experience

    I’ve been gardening for over 30 years. Don’t be impressed. The number of years spent with hands in the dirt doesn’t necessarily confer any particular expertise in the field (pun intended). Some gardeners do the same foolish things year in and year out, or never sufficiently investigate other, perhaps better, ways of doing what they’ve been doing. Or not appreciate cause and effect. (Was it really the compost tea spray that led to bountiful yields last year, or was it reliable rainfall interspersed with bright, sunny days? The tendency is to hold the former responsible.) Or, the wizened, old gardener’s wealth of knowledge might not extend beyond what they’ve grown on their own “back forty,” severely limiting the benefit of any wisdom passed on to others with a shorter history of gardening.
    Reading is a efficient way to squeeze wisdom of others, reflecting decades of digging, pruning, and seed-sowing, into just a few years, for yourself — depending, of course, on the weight of the words. The fact that so many gardeners have always gotten by with little or no reading is testimonial to millions of years of evolution that makes every pea seed naturally want to grow and every apple tree naturally want to bear fruit.
    So, in the spirit of becoming better gardeners, especially this time of year with nothing to do in the garden, let’s thumb through the pages of three worthy books that recently found a place on my desk.

Good Tools are a Help

    Did you know that the hose was invented by Jan van der Heijden in the 17th century? Tarred canvass, linen, and hand-stitched lengths of leather pipe were all predecessors of the modern garden hose, all of which I learned from Bill Laws’ A History of the Garden in Fifty Tools. It wasn’t until near the end of the 19th century that technology and marketing brought hoses into more general use in gardens.
 History of Garden in Fifty Tools   Just imagine having to water your garden with repeated trips to the spigot with your watering can, another of Mr. Laws’ “Fifty Tools.” Not that the garden hose has displaced watering cans, which have been around in various incarnations for hundreds of years and may have reached their peak in functional and visual elegance with the work of John and Arthur Haws. Haws cans are still made; my 2 gallon, galvanized Haws watering cans have served me and my plants well for over 20 years.
    . . . Fifty Tools will not, admittedly, make anyone a better gardener. Instead, it’s a very interesting history of 50 gardening tools with — okay, this might be some help in the garden — sidebars, “Tools in Action,” telling of the best use of each tool.

Haws watering can

Haws watering can

Some listing are a stretch of the word “tool:” a radio, a scarecrow, separate entries for plant container, terracotta pot, and stoneware urn? I would have included the garden cart, pitchfork, and hori-hori knife as necessary garden accoutrements.

Inspiration from Paris

    In and Out of Paris: Gardens of Secret Delight by Zahid Sardar, with photographs by Marion Brenner is slightly more practical than A History of the Garden in Fifty Tools, even if I’m not planning to garden in Paris or like a king. The first section, eye candy, has the usual gardens of a literally majestic scale: Versailles, the Tuileries, Vaux-le-Vicomte, etc.
Paris Gardens    Sections on private gardens are more inspirational for us non-royalty. Most of the gardens, whether majestic or small, are typically French, with long views or symmetric arrangements. Not one of the gardens, though, the 1000 square foot Japanese garden near the Bastille, with carefully placed, but not seemingly so, boulders nestled into mosses, lichen bordering a koi pond. Walls shield the garden from the sight and sound of the surrounding city, the effect softened with clumps of bamboo and a mix of evergreen and deciduous trees.
    One of the most interesting gardens is the Experimental Parc Méry-sur-Oise, which started life as the historic Renaissance-era Chateau de Méry-sur-Oise. More recently, in 1999, the grounds were re-done, this time with water features, not Paris, Pervergne gardentraditional fountains, but misty, hot, cold, brackish, and mineralized water that rains down from above or tumbles over waterfalls. Long-term goals, the “Experimental” part of the garden, include observations of the effects of the various waters on plants and the ecosystem over time. Elsewhere are free-standing gabion walls planned for vertical gardens. That never happened. Money ran out and the gardens have been neglected since 2003 — a modern, neglected garden!
    In all honesty, I mostly just looked at the beautiful photographs of In and Out of Paris: Gardens of Secret Delight.

Grow Vegetables? Study this Book

    Even if you are a backyard gardener rather than a market gardener, The Market Gardener, by Jean-Martin Fortier, will have you harvesting more and better tomatoes, and with less effort. Two themes of this book, as I see it, are planning and record-keeping. The author is a successful market gardener in Quebec, grossing over $100,000 from a mere acre and a half of land.The Market Gardener
    The growing units on Jean-Martin’s farm are raised beds 100 feet long by 30 inches wide. Having all beds the same makes it easy for him to calculate the amount of compost needed and keep track of yields. The latter are spelled out in a handy chart showing days to maturity and yield of individual vegetables per 100 foot bed. I haven’t calculated yields from my 17 foot by 36 inch wide beds, but do know that I need to plant 4 beds at two week intervals to harvest our fill of sweet corn to enjoy during summer and, frozen, through winter.
    Another useful table spells out spacing of transplants, in flats and in beds, and another lists dollars reaped per bed from various vegetables. The only other gardening book that quantifies small-scale vegetable growing so well, in this case strictly backyard growing, is Burrage on Vegetables, from 1954, by Albert Burrage. How times have changed: Burrage is pictured in his garden in sport coat and bow tie; farmers in Jean-Martin’s book are pictured dressed as, well, farmers.

1950s vs the present: Different look but 2 good gardeners

1950s vs the present: Different look but 2 good gardeners

    The book also has the requisite listing of each vegetable along with growing information as well as useful chapters on soil care (generally good but with some misconceptions) and microclimate. One particularly simple, cheap yet innovative technique described for weed control after harvest, between plantings, is covering a bed for 2 weeks with a reusable 6mm thick, black silage tarp.
    Jean-Martin emphasizes that it is possible for farming and gardening to be, at the same time, productive and bucolic only with planning and organization to avoid wasting time. In so doing, he can be a farmer who can put in a workday from a reasonable 8 to 5. Charles Dudley Warner wrote in his 1870 classic My Summer in the Garden, “Blessed be agriculture! If one does not have too much of it.” I agree.

Talks in Pennsylvania & Vermont Coming Up

Some good conferences and lectures coming up. I’ll be in Pennsylvania and Vermont talking about espalier fruits, weedless(!) gardening, growing hardy kiwifruit, pawpaws, and blueberries, the efficacy of compost tea, and pruning fruits. For details, see my “Lectures” page.

NOTHING TO DO? SEQUESTER CARBON?

Agriculture: Good or Bad for Our Planet?

    I’m enjoying this farmdening interlude, with essentially nothing to do, farmdenwise, for a few weeks. No planting, no pruning, no weeding. Seeds have been ordered and the greenhouse, full of lettuce and kale and chard and other fresh stuff, is cold enough to require no more than weekly waterings, if that. Even then, watering involves nothing more than a quarter turn of the mechanical timer to start water running through the drip irrigation lines.
    I’m going to use this lull as an opportunity to ruminate — on rumens and other relationships between agriculture and global warming.

Deb, first time herding some very big cattle

Deb, first time herding some very big cattle

    Let’s get started right away with the rumen, that part of the digestive system of a cow, steer, or other ruminant where cellulose is fermented. With a capacity of more than 50 gallons, a cow’s rumen is a veritable factory, one whose byproduct is a lot of gas, more than 200 gallons a day, belched out by the cow. No small thing, that collective burp of agricultural ruminants. It’s good for the cow (when you consider the alternative) but not so good for the environment. A significant portion of the effluvia is methane, a carbon compound which is 20 times more heat-trapping in the atmosphere than carbon dioxide.
    Let’s leave the cows alone and drop down to the soil. Global warming from the agricultural soils? Yes. Harvest a crop, any crop, and you’re removing nutrients from the site. So those nutrients need to be replaced, and that’s usually done with fertilizer. Fertilizer, unlike money, does, or can, grow on trees (such as honeylocust and others in the pea family, which garner nitrogen from the air a put it in the soil) but most fertilizer is synthetic. Synthetic fertilizer must be cobbled together using energy derived from fossil fuels, which then release carbon dioxide into the atmosphere.
    That’s not all. The soil itself is a large reservoir of carbon tied up in complex, organic compounds as well as in living and dead organisms. Stir that soil up with a plow, a tiller, or a garden fork, and you charge it with oxygen, just what bacteria, fungi, and other microorganisms are waiting for so that they can gobble up that carbon, grow and extract energy, then release carbon dioxide to the atmosphere.

Of Tillage and Biochar

    “Sequestration” isn’t only something done with our money by a bunch of mostly men in a big room (Congress) in Washington. It’s also done by farmers to save, not money, but carbon. The idea is to keep carbon in the soil rather than letting it “burn” to carbon dioxide, waft into the atmosphere, and contribute to global warming.

Me, a long time ago, burning carbon

Me, a long time ago, burning carbon

    Minimizing, or eliminating, tillage is one way to sequester carbon, something that can be done on a home or small farm scale, even on a large scale. I haven’t tilled my garden in over 20 years, and 22 percent of Midwestern farmland is no-till. Minimal tillage or no-till also brings other benefits, such as reduced weeds, a friendlier environment for earthworms and fungi, more efficient plant water use, more organic carbon in the soil for livelier biological activity and improved soil aeration, and, of course, the benefit of not having to till.
    Biochar is another proposed savior in these carbon-burning times. Biochar is, basically, charcoal, which is mixed into the soil. Charcoal starts out as wood which, when left in or on the ground, rots, the carbon within turning to carbon dioxide. Charring the wood drives off much of what makes up wood, leaving only black carbon, a poor food for soil microorganisms, so it does not rot. The wood’s carbon has been locked up, sequestered, changed from organic carbon to inorganic, or elemental, carbon.

Hold that Carbon, But Not Too Tightly

    When it comes to agriculture, keeping too tight a grasp on carbon is not a good thing. Agriculture, whether farming or gardening, isn’t Nature, or else my garden and yours would be all weeds (some of which would be edible and, hence, technically not “weeds”).Plowing field
    Carbon is energy, fueling growth of fungi, earthworms, and other creatures, and as it’s “burned,” nutrients associated with it are released into the soil in forms that plants can use. That’s a good thing, to a degree. Fermentation microorganisms within cattle rumen make cellulose available for energy and growth even as they release methane. That’s also a good thing, to a degree.
    Good gardeners and farmers strike a congenial balance, emulating Nature without giving her a free hand. Too many cows belching methane is not good for the planet. Too much tillage “burning” up soil organic matter and releasing carbon dioxide also is not a good thing.
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    A final word, about radishes, for no reason except that I am enjoying them right now. Winter radishes are large, variable in shape and color, and store well. Today, as I’ve done every few days since late fall, I sink my hand into a cold, wooden box full of wood shavings to pull out yet another Watermelon radish. Sliced open, this variety of winter radish looks much like watermelon and tastes — no, not like watermelon — but crisp, sharp, and slightly sweet. Highly recommended; sow seeds July 15th.

FRESH-PICKED SALADS ALL WINTER

Greenhouse, Coldframe, Hotbed = Fresh Lettuce, Mâche, & other Salad Fixings 

You can’t beat the luxuriousness of entering a greenhouse on a sunny, cold winter day, and hitting that welcome wall of moist, warm air. Once you get through that soft wall, you drink in the redolence and visual vibrancy of green, growing plants. All this is possible even with a relatively inexpensive greenhouse, such as mine, which is, basically, 2 layers of plastic film supported by sturdy, steel hoops (plus thermostats, a propane heater, a cooling fan, and a “squirrel cage” fan to inflate the space between the layers of plastic for better insulating value).

Fresh greens in the greenhouse

Fresh greens in the greenhouse

Still, a greenhouse — my greenhouse, at least — isn’t for virtual trips to Puerto Rico; It’s for growing edible plants, mostly fresh lettuce, celery, mâche, claytonia, and arugula to fill the salad bowl every day from late fall through early spring.

This same benefit, though, can almost be achieved much more simply and much more cheaply with a coldframe. A coldframe, in its most basic incarnation, is a box frame covered with glass or some other transparent material and within which plants are grown or protected through the coldest months.

I have both a greenhouse and a coldframe. The coldframe came first. With a greenhouse full of greenery, I admit to usually neglecting the coldframe, which is unheated and only 25 square feet in contrast to the greenhouse’s heated 750 square feet. Still, last fall I had an extra 25 lettuce transplants and lacked even a square foot of extra space in which to plant them in the greenhouse. So I spread an inch of compost in the coldframe, firmed the transplants into holes there, and then gave the whole bed a good watering before replacing the cover.

Cold frame with cover closed, and Sammy

Cold frame with cover closed, and Sammy

Except for one subsequent watering, I’ve pretty much ignored the coldframe. The polycarbonate (‘Exolite’) cover is translucent so the coldframe’s innards are hidden from view unless the cover is lifted. Today, mostly out of curiosity, I lifted the cover to see what was going on inside. The lettuce was alive and had grown. Fall weather was admittedly relatively mild although temperatures here did drop below 10°F at least one night — pretty good survival for plants growing in little more than a covered box outdoors.

With short days and cold weather, lettuce is growing very slowly. Individual leaves, perhaps whole heads, probably will not ready for harvest until towards the end of February. That’s if the lettuce survives that long, which it might not even in the coldframe, depending on the length and depth of winter cold. Spinach would more likely make it through winter; mâche and claytonia would definitely weather the coldest days and nights.

Beefing Up the Coldframe

In the absence of a greenhouse, I would beef up coldframe salad production to yield more  and for more of the winter. I would, first of all, construct more coldframes because, with slow growth inside in winter, one harvest could decimate the crop, for a period at least, from just one coldframe.

Anything that helps the coldframe fend off cold and retain heat would also help increase the amount and duration of harvest. Insulating the sides helps, and said insulation need be nothing more than wood chips or straw piled up against the sides. Or make the box itself out of whole bales of straw!

Cover open, Sammy on guard

Cover open, Sammy on guard

Heat rises and glass and plastic are poor insulators, so most of the heat is lost through the translucent or clear covering. The Exolite cover on my coldframe is actually 2 layers of polycarbonate plastic sandwiching polycarbonate ribs that hold the layers 1/4” apart, proving better insulating value than a single layer. On really cold nights, an insulating mat, even just a blanket could be thrown over the cover. In Europe a hundred years ago, cold frames were used extensively for commercial vegetable production, and mats of woven straw covered the glass to keep out the coldest weather.

A few feet down into the earth, temperatures remain constantly in the 50s. That earth is a source of heat, tapped into by sinking the floor of the coldframe a couple of feet deeper, which also allows head space for taller vegetables, such as Romaine lettuce. Too deep, of course, makes harvesting very inconvenient.

And finally, winter production can be beefed up by actually heating a coldframe, in which case it’s no longer a “coldframe” but what’s called a “hotbed.” The traditional heat source for a hotbed is horse manure, layered into the bottom of the bed after a foot or so of soil has been dug out. A certain art is involved in getting the right amount and moisture content of manure, packed in just right and then covered with soil for a steady even heat. I made my coldframe into a hot bed a couple of years ago, or, rather, tried to. I didn’t get it just right; will have to try again.

True, you can’t climb into a coldframe for a tropical junket, but the coldframe, with care, can become a hotbed of tasty, fresh, organic, very locally-grown vegetables from fall to spring.

To Every Thing There is a Season

Pruning is reduced to small steps, in time & process

So many branches, so little time. Or so it seems. Annual pruning is needed to get the best out of most trees, shrubs, and vines, of which there are many here on my farmden.

But wait. My brother once remarked — and the remark rang true — that a large part of feeling overburdened from so much to do comes from thinking about it, rather than doing it. And now that I think about it — if I may be allowed a bit more thought — many trees, shrubs, and vines do not need annual pruning except for size control, in which case a different plant or dwarfer variety could have been planted. My witch hazel shrub is in that hardly-ever-needs-pruning category, as is fothergilla, goumi (an attractive shrub with tasty fruits), mountain laurel, and rhododendron. 

Witch hazel is a shrub needing little or no pruning

Witch hazel is a shrub needing little or no pruning

Most ornamental trees do not need annual pruning, and the same can be said for ornamental vines, except when they threaten to take down an arbor, fence, or trellis that is lending them support.

Mostly, what needs annual pruning are flowering shrubs, and trees, shrubs, and vines that bear tasty (to us humans) fruit. But exceptions exist even among those edibles. Fruit plants that hardly ever needing pruning include such delicacies as pawpaw, persimmon, huckleberry, juneberry, Nanking cherry, elderberry, and lingonberry.

All shrubs are pruned the same, sort of

I already feel like pruning is under control, without even lifting a finger. And usually I don’t lift a finger to prune until, as is commonly recommended to avoid winter cold damage, after early February, when the coldest part of winter has passed. The last couple of years, though, I decided to go ahead and get a jump on pruning my rather extensive collection of gooseberries and currants. These plants are very cold-hardy so would be expected to laugh off winter cold, even following a December pruning, and they have.

Pruning currants and gooseberries captures the essence of pruning any flowering or fruiting shrub. Shrubs are shrubs because they are shrubby (duh!). That is, their stems are not long-lived but new stems, called suckers, are always popping up through the ground to replace old, decrepit ones. So these shrubs are “renewal pruned.” Old stems are cut away and the number of new stems, if too many, are reduced so that they don’t become crowded as they age.

Gooseberry bush, before & after pruning

Gooseberry bush, before & after pruning

The questions then become, “How old is too old for a stem, and how many new stems is too many?” The questions are related because shrubs whose old stems perform well in terms of fruit or flowers also tend to make fewer suckers, and vice versa. The easiest way to approach shrub pruning (and the way it’s detailed in my book The Pruning Book) is to group shrubs into one of four categories. At one end of the spectrum are shrubs that flower or fruit well on very old wood and make few suckers — and, hence, are in the aforementioned hardly-ever-needs-pruning category. At the other end of the spectrum are shrubs that flower or fruit only on new stems, such as butterfly bush, so can have every one of their stems lopped to ground level every year.

A now I do it, prune currants & gooseberries

The other day I stopped thinking about pruning my gooseberry shrubs and, instead, approached them with lopper and hand shears and a new-found sense of having all the time in the world. Gooseberries fruit best on stems that are 2 and 3 years old. Pruning is straightforward. Merely lop to the ground any stems more than 3-years-old (they were 3-years-old last season and bore fruit) and reduce the number of new stems to about a half-dozen of the sturdiest, most upright ones. The ideal, pruned gooseberry shrub, then has about a half-dozen each of 1, 2, and 3-year old stems. A shrub never becomes a tangle of stems nor has old, decrepit, unproductive ones.

Black currant, before pruning

Black currant, before pruning

Red, white, and pink currants get pruned exactly the same as gooseberries; black currants, though, are a whole ‘nother animal. They bear best on 1-year-old stems and, to a lesser degree, 2-year old stems. So for the black currants, I lopped back to the ground any stems more than 2-years-old as well as some 2 year olds and thinned out new, 1-year old stems, again to the best half-dozen.

How do I know the age of any shrub’s stem? I could count back the age of the various side branches starting at their tips. That would be tedious. The thickness of the base of a stem and the appearance of the bark are just as telling. Old bark is darker and, often, peeling.

After pruning any shrub I go over the plant to remove or shorten stems that will droop so low as to set their fruits on the ground. Especially with strictly ornamental shrubs, I also lop back any stems shooting gawkily skyward or otherwise looking out of place. And then, for any shrub, ornamental or fruiting, I step back to evaluate and admire my handiwork.

Black currant, after pruning

Black currant, after pruning

The why, how, and details of pruning any plant

For more about how to prune everything from houseplants to delphiniums to maples to raspberries, check out my book, The Pruning Book.

Live, On Stage Now!!!

I’ll be giving a number of lectures at various venues over the next few weeks. For a listing of what and where, see Lectures.