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Cats with potted begonias

IS REAL SOIL GOING TO POT?

What’s in Your Mix?

That potting soil that you’ve bought for your seedlings and houseplants? It probably has no REAL soil at all in it. Real soil is just too hard to obtain in reliable and uniform quantities for commercial packaging. Soilless mixes, as commercial potting soils are (or should be) called, are a mix of some kind(s) of organic materials along with some aggregate, with possible additions of fertilizer, ground limestone, and a wetting agent.Cats with potted begonias

Organic materials in these mixes help sponge up water and cling to nutrients that might otherwise wash down and out of the pot. Peat moss is the organic material traditionally used in soilless mixes. Although it holds water well, it’s initially hard to wet, which is why wetting agents are sometimes added to soilless mixes. Read more

BREWING UP BATCH OF POTTING SOIL

Prime Ingredients for Any Potting Mix

Many years, my gardening season begins on my garage floor. That’s where I mix the potting soil that will nourish seedlings for the upcoming season’s garden and replace worn out soil around the roots of houseplants. Why do I make potting soil? Why does one bake bread?

There is no magic to making potting soil. When I first began gardening, I combed through book after book for direction, and ended up with a mind-boggling number of recipes. The air cleared when I realized what was needed in a potting soil, and what ingredients could fulfill these needs. A good potting soil needs to be able to hold plants up, to drain well but also be able to hold water, and to be able to feed plants. The key ingredients in my potting mix are: garden soil for fertility and bulk; perlite for drainage; and a mix of peat moss and compost for water retention. 
Components of potting soil
Why not just dig up some good garden soil? Because a flower pot or whatever container a plant is growing in unavoidably creates “perched water table” at its bottom. Garden soil, even good garden soil, is so dense that it will wick too much water up from that perched water table. Waterlogging is apt to result, and waterlogged soil lacks air, which roots need in order to function. (More about perched water tables and lots of other stuff about soil, propagation, plant stresses, and more can be found in my book The Ever Curious Gardener: Using a Little Natural Science for a Much Better Garden.)
Perched water table
Coarse mineral aggregates — perlite, in my mix — make potting soils less dense, so water percolates more readily into the mix, through it, and out the bottom of the container. Other aggregates include vermiculite, sand, and calcined montmorillonite clay (aka kitty litter). I chose perlite because vermiculite breaks down with time and can contain asbestos. Sand is heavy, although this can be an effective counterbalance for top heavy cactii.

The peat moss and compost in my mix are organic materials that slurp up water like a sponge; plants can draw on this “water bank” between waterings. One peat to avoid is “peat humus,” a peat that is so decomposed that it has little water-holding capacity. Organic materials also buffers soil against drastic pH changes and cling to nutrients which are slowly re-released to plant roots. Otherwise these nutrients run out through the bottom of seedling flats and flower pots. 

Peat is relatively devoid of nutrients but the compost provides a rich smorgasbord of nutrients. And I can brew it myself. Just letting piles of autumn leaves decompose for a couple of years produces “leaf mold,” which has roughly the same properties as compost.

Potting soils made with garden soil and compost might need to be pasteurized to eliminate pests especially weeds. Too much heat should be avoided, however, because toxins which injure plants will form and beneficial organisms will be eliminated. When I am going to pasteurize, I do so only to the garden soil in the mix; my composts get to above 150°F all on their own.

To pasteurize potting soil, put it in a baking pan, bury a potato in it, and bake it in a medium oven. When the potato is baked, the soil is ready. Pasteurization is not absolutely necessary; I pasteurize to kill weed seeds.Begonia, Mandarin & cats

What You Buy Isn’t . . . 

Go out and buy a potting mix and, in all likelihood, that mix will be devoid of any real garden soil. You can mix up a so-called “soil-less” potting mix by sieving together equal volumes of peat moss and perlite. Since the mix has no garden soil or compost to supply nutrients, add 1/2 cup of dolomitic limestone, 2 tablespoons of bone meal, and 1/2 cup of soybean meal to each bushel of final mix. This mix has enough fertility for about a month and a half of growth without additional fertilizer.

I favor traditional potting mixes, which contain real garden soil. Real soil adds a certain amount of bulk to the mix, as well as a slew of nutrients and microorganisms. Real soil provides buffering capacity, which allows for some wiggle room in soil acidity.

The Magic Happens

I wrote early on, “There is no magic to making potting soil.” I could toy with ratios and make a potting mix from perlite plus compost, perlite plus compost plus garden soil, even straight compost, depending on the texture of the compost.

Going forward, I’m going to experiment with coir and/or PitMoss, both possible substitutes for peat moss, the harvest of which is environmentally questionable.

For my first batch of potting mix for this season, I’ll stick with my usual recipe. Step one is to give the garage floor a clean sweep. potting soil, piling ingredientsThen I pile up on the floor two gallons each of garden soil, peat moss, perlite, and compost. On top of the mound I sprinkle a cup of lime (except if I’ve sprinkled limestone on the compost piles as I build them), a half cup soybean, perhaps some kelp flakes.

This is a mixed bag of ingredients, but I reason that plants, just as humans, benefit from a varied diet. I slide my garden shovel underneath the pile and turn it over, working around the perimeter, until the whole mass is thoroughly mixed. potting soil, mixingI moisten it slightly if it seems dry. When all mixed, the potting soil gets rubbed through a 1/2″ sieve, 1/4” if it’s going to be home for seedlings.potting soil, sifting

I end by clicking click my heels together three times and reciting a few incantations to complete this brew that has worked its magic on my seedlings, houseplants, and potted fruits each season.

Winter Prep for Some of my Figs

Fig Abuse?

Anyone watching what I was doing to my fig trees might have called “Fig Protective Services” to have my trees removed to a new home. But figs are tough plants and tolerate a lot of what looks like abuse.

Let me offer some background: Figs are subtropical plants so can’t survive to fruit outdoors around here. I grow a few fig trees in pots that I can put in a protected location for winter (more on that later). Problem is that the trees’ roots eventually fill the pots and exhaust  nutrients in the mix.

I could move each tree to a larger pot. Then the branches could grow commensurately larger, and more growth of branches translates to more figs to harvest. But these pots have to be moved every spring and fall, and there’s a limit to how big a pot I can handle.

The other way to give the roots new ground to explore is to root prune them. That is, slice off some roots to make space for new soil in the same pot. Trust me; I’ve done this for many years and the plants tolerate it well, growing happily each spring following the operation. (Fall or spring, when the plants are leafless, is the best time for root pruning and re-potting.)

So I tipped each plant on its side and pulled on the stem while holding the pot in place to slide the root ball out of the pot. Sliding root ball out of potAfter standing the root ball upright, I started slicing it from top to bottom. For root balls 18 to 24 inches across, I slice a couple inches off all around. I used to use an old kitchen knife but discovered that my reciprocating saw with a medium-tooth blade works much better.Slicing root ball

With the old root ball shrunken, it goes back into its pot and I start packing potting soil back in the space between the pared down root ball and the sides of the pot. Adding new potting soil to potFor good contact, I pack the potting soil in with my fingers and the flat end of a 3/4 inch dowel.Packing new soil in around root ball

Next year at this time or, at most, two years from now, trees will get root-pruned again.

Winter Quarters

Now, what will I do with the fig trees for winter. It’s a conundrum, because the trees, being subtropical, do well with a cold season rest, ideally below 50°. On the other hand, they can’t tolerate cold much below about 25°F. in their pots.

Some places that might provide temperatures within this range are an unheated garage that’s attached to a house, an unheated and uninsulated basement, or an unheated foyer or mudroom.  As long as they are dormant, the plants do not need light. 

For many years, I’ve lugged my plants down the rather narrow stairway to my basement. There’s an oil burner down there but it’s rarely used since most of our heat is with wood. In midwinter, basement temperatures hover around 40°F.

As of this year, my days of lugging the heavy pots down stairs are over. I now have access to a ground level, unheated room in a well-insulated, rarely heated building having a concrete floor for good thermal mass. The Ritz!

The goal is to keep the plants cold enough so that they stay dormant until it’s safe to move them outdoors in spring. If all goes well, the plants are still dormant when outdoor temperatures rarely dip below 32°F. Then the plants, moved outdoors, slowly awaken with cool temperatures and bright sun promoting sturdy growth.

Because fig trees in pots tolerate temperatures down into the 20s, there’s no rush to move them into storage. I usually wait until sometime in December.

What Makes Soil Potting Soil?

Notice that I mentioned my trees growing in “potting soil.” Straight soil, even good, well-drained garden soil, is unsuitable for plants in pots because it becomes unavoidably waterlogged. (The reason, described in my book The Ever Curious Gardener: Using a Little Natural Science for a Much Better Garden, has to do with what is known as a “perched water table;” take my word for it or read the book.)The Ever Curious Gardener

Drainage is improved in potting soils by adding aggregate such as perlite, vermiculite, or calcined montmorillonite clay (the latter better known and more often sold as kitty litter).

Roots in containers have more limited volume to explore for nutrients, so potting soils also need to be richer that even good garden soils. Compost is one way to provide nutrition. Among the advantages of compost is its ability to offer nutrients over a long period of time, as soil microbes slowly decompose it.

Water, like nutrients, also must be accessed from a limited volume of soil. The compost helps a potting soil hold water; I boost that further with the addition of some peat moss or coir.

My finished mix is made up of equal parts garden soil, perlite, compost, and peat moss. All my plants, not just the figs, like it.

Peat, perlite, soil, and compost

Peat, perlite, soil, and compost

Peppers & Potting Soil

Concerned

You’d think that there’d be no reason for me to be concerned. After all, year after year I raise my own seedlings for the garden. Nonetheless, every day I take a look at the small tray of soil in which I had sowed eggplant and pepper seeds, waiting for little green sprouts to poke through the brown surface of the potting mix.

These plants are on a schedule. They get a start indoors — in a greenhouse now; under lights or in sunny windows in years past — so that they have enough time to start ripening their fruits by midsummer.

Italian Sweet peppers

Italian Sweet peppers

Even an early-ripening pepper wouldn’t ripen its first fruits before October if seeds were sown directly in the garden once the soil had warmed enough for germination, which isn’t until the end of May around here.

Ingredients for Good Transplants

Not that raising transplants for the garden is difficult. All that’s needed is attention to details, the first of which is using seed that is not too old. The dry tan pepper and eggplant seeds might not look alive, but they are. And they do age. Under good storage condition — cool and dry — pepper seeds retain good viability for only a couple of years, eggplant seeds for 4 years.

Next in importance is the container and potting mix. Old yogurt containers, egg cartons — people have come up with all sorts of containers for growing transplants. They’re all fine as long as they’re at least an inch and a half deep and have holes in their bottoms to let excess water drain out.

Garden soil, even good garden soil, is not suitable for containers. It stays too wet, suffocating roots. So all potting mixes contain aggregates, such as sand, perlite, vermiculite, or calcined clay (a.k.a. kitty litter), which are large mineral particles that make room for air in the mix. Mixes also contain some organic material, such as compost, peat moss, or coir (made from coconut waste), to help them retain moisture.

You can purchase potting mixes made with or without real soil in them, and either sterilized or not. Sterilization kills potential pests that might lurk in the raw ingredients. Not sterilizing keeps living things, including potential enemies of any potential pests, alive in the mix. I make my own mix, usually unsterilized, from equal parts compost, garden soil, peat moss, and perlite.

With seeds sown and then covered with about a half inch of potting mix, the container is gently watered, then covered to keep in moisture.

Warmth is the next ingredient for good germination. Seeds need more warmth to sprout than than a seedling needs for good growth. In the case of pepper and eggplant seeds, between 70 and 80° F. is ideal for sprouting. The top of a refrigerator might provide a warm home for the seeds to get started, as might a shelf above a radiator. I use a soil heating mat.

The last ingredient in raising seedlings is the most difficult one for me to provide, at least with pepper and eggplant seeds. Patience. Even under good conditions, these seeds might take a week or two to sprout. All I need, then, is to be rational. I sowed the seed on March 5th; I provided good conditions. As I write this, it is March 12th. One week, a not unreasonable time for the seeds not to yet show signs of life.

Not to Worry

Growing transplants is generally easy. Although I’m a little concerned until pepper and eggplant sprouts emerge, I’m more laid back with pretty much all other seedlings. Tomatoes, for example, are among the quickest and easiest to grow, and, because of the wide choice of varieties when growing your own transplants, very satisfying.

Once the peppers and eggplants sprout, they, like other sprouts, need to be moved to where they are bathed in light. Along with light, slightly cooler temperatures from then on make for sturdy, healthy growth. And then, towards the end of May, out to the garden they go.

Update: March 17th. I was about to re-sow the pepper seeds. But first I checked the ones sowed March 5th. They sprouted!Pepper seeds sprouting

OLIVE HARVEST IN FULL SWING HERE

What To Do With This Year’s Harvest?

Olive harvest will begin — and end — here this week. Yes, it’s late. After all, the harvest in Italy was in full swing weeks ago, back in autumn. But this is the Hudson Valley, in New York. What do you expect?
    I’m talking about harvesting real olives, not Russian olives (Elaeagnus angustifolia) or autumn olive (E. umbellata), both of which grow extensively in a lot of places, including here. Too extensively, according to some people, which is why they’re listed as “invasives” and banned from being planted in some regions. (But their fruits are very tasty, their flowers are very fragrant, their leaves are very ornamental, and their roots enrich the soil with nitrogen from the air, all of which garnered them a chapter in my book Uncommon Fruits for Every Garden.)Olive tree in a sunny window
    Present harvest here is of the true olive (Olea europaea), unrelated to the previously mentioned olives. Temperatures in the Hudson Valley, and beyond, would spell death to an olive tree, which is cold-hardy to about 14°F, so my tree is planted in a pot, just like my other Mediterranean-climate plants — fig, pomegranate, feijoa, black mulberry, bay laurel, kumquat, black mulberry, and Golden Nugget mandarin (tangerine). I can handle only so many potted, small trees, so it’s lucky that my olive doesn’t need a mate to bear fruit; it’s the self-fruitful variety Arbequina. The plant I got a few years ago from Raintree Nursery started bearing its first season!
    Unlike my fig, pomegranate, and mulberry, olive is evergreen, so it needs light year ‘round. Fig, and company, are in a dark corner of my cold basement, dormant. The olive is in a cool room basking in sunlight from a south-facing window.
    Two years ago, after an auspicious start, only one olive remained on the tree in late summer. I think my duck ate it.
    This past fall, the harvest has increased many-fold — to almost a dozen fruits. What with being knocked around when moved indoors and the change in environment, about half that number of fruits now hang from the branches.
    I like my olives fully ripe, black, so have let them hang as long as possible. Some are beginning to dry and shrivel, so it’s time to harvest. Fresh, the fruits are unpalatable, with a bitterness that comes from oleuropein. That bitterness is removed by curing and fermentation using lye, salt, and time. I’ve had naturally cured olives that use only the last ingredient, time, and that’s how I’m going to try mine.

For More Than Just Olive Fruits

    A few years ago, I almost got rid of my olive tree. After all, it wasn’t making a dent in my olive consumption. Then someone pointed out that the olive, for thousands of years, has been a symbol of peace. That alone should be enough reason to keep the tree, and it was.
    Also, the tree is pretty and long-lived — thousands of years, as documented by radiocarbon dating.

Secret Soil Recipe, Divulged (Again)

    In preparation for the upcoming gardening season, I brought pails of frozen potting soil, compost, and soil in from the garage/barn. Soon I’ll need to trim back roots and repot some of those Mediterranean-climate fruits, including my Arbequina olive. Not my Meiwa kumquat, though, some of whose green fruits are showing hints of yellow, foreshadowing ripening to begin over the next couple of months. Trimming back its roots would cause branches to let go of fruits.
    Potting soil will also be needed for the first seeds of the season, to be sown indoors in the next week or so.
 Mixing potting soil   I will now divulge my recipe for potting soil. The main ingredients are garden soil, compost, peat moss, and perlite. I thoroughly mix together equal volumes of these four ingredients, then add a cup of soybean or alfalfa meal (for extra nitrogen). If I’m feeling generous, I also throw in a half a cup or so of kelp meal (for micronutrients, although it’s probably superfluous with the panoply of nutrients from the compost). Perhaps also a half a cup of dolomitic limestone (for alkalinity, calcium, and magnesium, also probably superfluous with the buffering action and richness of the compost). Using wooden frames onto which I’ve stapled 1/2 inch hardware cloth, I sift together the mixture.
    Ten gallons of potting soil should carry me through winter until the compost piles and the soil have defrosted.

Olive Curing Update

Olives harvested and cured.

Olives harvested and cured.

   It’s now some days after I first wrote the above. Olives received no other treatment except being left to dry and wrinkle. Tasted them today —  delicious! (I’m going to plan for bigger harvests for the future.)

The Season Begins

Gentlemen (and ladies, and kids), start your engines. The 2014 gardening season has begun, here on the farmden, at least.
The day began with my lugging the big pail of potting soil from the cold garage to a warm spot near the woodstove. My home-made potting soil — equal parts peat, compost, garden soil, and perlite, with some soybean meal thrown in — is moist when I make it, so was frozen solid. Not usable or suitable for germinating seeds.
Once the potting soil defrosts and warms, I scoop it into a seed flat and a small plastic tub into which I’ve drilled drainage holes. Firming the soil in place with my Furrow Maker, a small board with spaced out,
The Furrow Maker in action

1/4-inch dowels glued to its underbelly, creates a miniature farm field. Into the tub’s “field” go rows of fresh onion and leek seeds (fresh is important with these seeds, which lose viability after a year or two), about 7 seeds per inch, which is enough to well populate the “field” without causing crowding. After the seeds are covered with soil and gently and thoroughly watered, the tub gets covered with a pane of glass and placed on a heating mat that provides gentle warmth of between 70 and 80 degrees F.

I could sow onion seeds outdoors in early spring. The onions I’m growing, and the ones all northern gardeners should be growing, are so-called long day (in fact, short night) varieties. Their leaf growth comes screeching to a stop in early summer’s 15 or

16 hour days. The plants shift gears and redirect their energy into pumping up growing bulbs. More leaves at that time means more stored energy available to swell up sweet, juicy bulbs. That’s what I want and why I go through the trouble(?) of early, indoor sowing. I’ll plant out the seedlings in early May.

The small seed flat gets similarly filled with potting soil and sown with seeds, lettuce seeds in this case. Greenhouse lettuce is still going strong but I want to have some transplants ready for when the older stuff peters out. A 4 by 6 inch flat with four furrows of lettuce seeds should provide all the lettuce transplants I need for many weeks.
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A greenhouse full of only lettuce could get boring. Other sorts of edible greenery currently share the space, and will continue to do so in the coming weeks. Some has been planted, and some has planted itself.
Among the planted greenery is a whole bed of kale and Swiss chard livened up with a couple of fennel plants. Also mâche, which usually plants itself except that overly diligent weeding in the greenhouse
Fennel, chard, lettuce, and kale in this bed

necessitated transplanting self-sown mâche from outdoor garden beds into the greenhouse last September.

Self-sown greenery includes claytonia (miner’s lettuce), minutina, and — more familiar to most people — celery. Claytonia doesn’t have much flavor but adds texture and color to a winter salad. The same goes for minutina, which is actually an edible species of plantain (the common lawn weed, not the banana relative). Celery plants are in various stages of growth. We’ve been eating the mature ones for months and the smallest seedlings will be ready for transplanting out into the garden in early May.
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So my friend Bob is over for a visit. It’s near lunchtime and he beelines for the freshly baked loaf
Celery for eating and celery babies for transplanting

of bread sitting innocently on the kitchen counter. Bob grabs a knife and already has a sandwich in mind. “Do you have any tomatoes,” he says. What? Tomatoes? It’s midwinter!

I guess he’s made the link gardening-greenhouse-tomatoes. Never mind winter. Sorry, not in my greenhouse in winter, for a few reasons.
Fruiting demands a lot of a plant’s energy. That energy comes from the sunlight. Even though the sun has been rising higher in the sky and for longer periods daily, its light is still paltry compared to midsummer sunlight. A bright summer day bathes the garden with about 10,000 foot-candles of light. My greenhouse, according to measurements taken at high noon on this crystal clear day, is bathed  with about 6,400 foot-candles of sunlight.
Natural sunlight could be supplemented with artificial light. Not a table lamp or even a bank of fluorescents, though. Light intensity falls off as the inverse square of distance from the light source; double the distance and you’ve got only one-quarter the intensity. So plants need to be close to the light source, which then will shade natural sunlight. Special high intensity bulbs are needed to make a dent in winter’s relative darkness.
And then there’s the temperature needed to raise a crop of tomatoes in February. For tomatoes, I wouldn’t want temperatures lower than in the 50s. My greenhouse heater kicks on at 37°F. Each degree of warming increases heating costs about three percent.
Winter tomatoes don’t seem worth the extra cost in dollars and to the environment from increased usage of gas or electricity. And they don’t taste that good. I can wait.

A Jump on Spring

I got a jump on spring yesterday and started pruning hardy kiwifruit vines. The fruit is a kissing cousin of fuzzy, market kiwis, except, with smooth skins and small size, they can be popped whole in your mouth like grapes. Hardy kiwis are also cold-hardy, which their cousins are not.
The vines need yearly pruning to let light and air in among the stems for productivity and plant health, to keep fruiting stems within easy reach, and to stimulate new stem growth each year off which grow fruiting shoots the following year.
My plants are trained on 5 wires strung between T-trellises, one wire down the middle of the trellis flanked by 2 wires on either side of that central wire. Each plant’s trunk rises up to the middle wire and then divides into two cordons, or permanent arms, that run in opposite directions along the middle wire. Fruiting arms, which are 1-year-old stems, grow off perpendicularly to the cordon to drape down over the outside wires.
As I approached the vines with shears, lopper, and small saw in hand, the vines looked back at me like an intimidating, tangled mess. Three steps in pruning brought everything in order. I first cut back all fruiting arms to within a foot or so of the outside wire and shortened each cordon back to where it began growth last year. Arms bear fruiting shoots near their bases so don’t need the whole of their lanky stems. As to the cordons, if they were allowed to grow longer and longer, one plant would tangle into the next plant down the row.
Next, the hardest part: I reached into the remaining tangle to cut back fruiting arms that have, over the years, begun to originate further and further off the cordons. These got shortened so that new shoots, for fruit 2 years hence, would originate closer in to the cordons. Left to their own devices, as they are in the wild on the edges of Asian forests, the vines would be climbing 100 ft. high on anything on which they could grab hold.
Finally, I thinned out most of the remaining fruiting arms so that they are about a foot apart. I’ll do a final pruning in spring, thinning more where needed and shortening all fruiting arms to their final length of about 18 inches long.
I’m left now with a pile of prunings. Their intertwining stems make nice decoration. I could also save some for my cat. Kiwi stems have a pleasing effect on the cats, similar to catnip. In Asian zoos, they have been used to calm “large cats.”
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What joy a mere sprout can foreshadow! Late last summer a gardening friend gave me some sprouts from her Maid of Orléans jasmine (Jasminum sambac). By the end of summer, a few of the cuttings had rooted and even flowered.  The plant or its flower wouldn’t win (or lose) any beauty contests, but is well worth growing for its unabashed fragrance. The aroma is sweet and rich and not at all cloying, even after the flowers fade.
What’s more, this jasmine flowers freely. As a matter of fact, it just finished its second round of flowering. Contrast this behavior with my two plants of common jasmine (Jasminium officinale). These latter plants occasionally cough forth a few flowers in late winter but nothing like the profusion of white blossoms they once did. I’ve tried everything, from starting new plants from cuttings to pinching shoots all summer until August to keeping them cool in until late winter to keeping them dryish until late winter to keeping them cool and dryish until late winter to keeping them in the greenhouse to . . .  you get the picture.
The only dark cloud hovering over my Maid of Orleans was the potting mix. Something seemed not quite right with it, having me worried that the plant might not grow or, worse, expire (as did the plant from the gardening friend from whom I got the cuttings). Not that this is a time of year to expect growth from any plant.
But now, that cloud has moved on. The new sprout looks happy and healthy and foretells of a fragrant future.
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I mixed up a new batch of potting soil, which I’ll need anyway in a couple of months for indoor sowing of the first seeds of next season. Into a 5 gallon bucket went finished compost and soil, equal parts, sifted. Into another 5 gallon bucket went peat moss and perlite, equal parts, sifted. I tipped the contents of both buckets together into the garden cart, sprinkled on 1 cup of soybean meal and a handful of kelp, and repeatedly slid a flat-bladed shovel under the pile and turned it over and over. Once everything was thoroughly mixed, I shook and forced it again through the 1/2-inch sieve and packed it away into buckets.
This potting mix will be home to the roots of seedlings and houseplants, as well as large, potted fig trees, roses, and pomegranates. Also, to Maid of Orleans, as soon as she outgrows her present quarters.

A Reel Mower, Potting Soils

Coming out of the gate of the warmest and driest winter in decades, weather this spring has been a roller coaster ride. March had a spate of sunny days in the 70s, then temperatures plummeted to the low 20s, then the dry spell was ended with some rain, and recently temperatures have continued on the seasonably cool and cold side. Lawngrass has enjoyed the weather, and during one of the recent calms I finally got the opportunity to roll out the lawnmower.


The opportunity!? Mowing the lawn isn’t usually one of my favorite pastimes but this spring I was anxious to try out my new lawnmower. No need to clean and tighten the sparkplug, check the gas and oil, and pray for  the roar of exploding gasoline (within the engine) with this new mower. It’s a push mower, “push” as in your pushing gets it moving and turns the front reel that lops grass cleanly as the sharp blades rotate pass the fixed bar.


Push mowers have come a long way since those heavy, iron monsters of yore and my new Fiskars Reel Mower was a joy to use. So much s that I was able to do a “Tom Sawyer” on my visiting brother and his two daughters, letting them vie to see who gets to create that musical whirring of the gears accompanied by a broad fountain of grass blades flying up and out in front of the traveling mower. (He ordered one for himself when he got home.)


Using a push mower is more than just fun, of course. It’s good for the environment. A gasoline powered lawnmower pollutes as much in an hour as a car driving 250 miles; pollution from electric corded or battery powered mowers depends on how the electricity is generated. A push mower offers the opportunity for productive exercise. And reel mowers make cleaner cuts than rotary mowers so result in a healthier lawn. I highly recommend Fiskars Reel Mower.
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A few weeks ago I fingered possible blame for poor seed germination and poor seedling growth on my having substituted peat moss for coir in my potting mix. Coir is a sustainable byproduct of coconut processing; peat moss takes eons to form so is not sustainable.


I’m happy to report that I was wrong. My seeding failures, it turns out, were due to the heating pad that is meant to provide gentle bottom heat for seed germination in my cool temperature greenhouse. Instead of the desired 75°F., the thermostat for that heating pad had been inadvertently turned up to 100°F (probably by me)!


Gardening brings into play the interaction of all sorts of physical, chemical, and biological system; the interactions are complex and this complexity makes it hard to ascribe cause and effect. But gardeners too often do this, just as I did (with reservations) relating coir in my potting mix to poor seed germination and seedling growth. 


To really find out if “A” causes “B,” (for instance, that coir is bad for seed germination) you have to control as many variables as possible (same seeds, same light, same watering, etc.) and then apply “A” to only half of your plants. It’s often not all that easy to control other variables. And anyway, if you start out believing that something — compost tea, for example — is going to make your plants grow better, you’ll be wont to not use it on all your plants. And then, if the summer happens to be sunny and warm with timely rains, you still might be inclined to tout that something — the compost tea, in this example — for good growth.
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My coir blunder did have the benefit of making me more objective about what makes a good potting soil. Many years ago, after much research, I came up with my own not-secret potting soil recipe of equal parts compost, garden soil, peat, and perlite with some soybean meal and kelp thrown in for extra nitrogen and micronutrients. Coir, in my last mix, substituted for all the peat.
After thinking that coir ruined my mix, I made up a batch of potting soil using 3 parts leaf mold (thoroughly rotted leaves) with one part perlite, again with some soybean meal and kelp. And then I actually did an experiment, planting half my lettuce seedlings in the leaf mold mix and the other half in the coir mix. Once removed from the overheated heating pad, seedlings grew equally well in either potting mix.


Which is to say, with reference to religions or potting soils: Many roads lead to the mountaintop. A good potting mix needs to drain well, hold moisture, provide nutrients, and provide a biologically friendly environment for roots. Perlite, sand or vermiculite can provide good drainage. Compost, peat, coir, or leaf mold help hold moisture and provide a biologically friendly root environment. Soil, compost, leaf mold, soybean meal, and kelp can provide nutrients. Various combinations of these ingredients make equally good potting mixes.