Of Worms and Leaves, Here and Beyond
Unreiking is Good Exercise
For the past few days I’ve been engaged in the esoteric exercise of unreiking. Basically, this involves lifting heavy (or sometimes light) sacks, slitting them with a knife, and then moving my arms back and forth over the spilled contents. Okay, okay, the “sacks” are plastic bags, their contents are autumn leaves, and I’m holding a pitchfork in my hands as I spread out the spilled leaves.
Sammy is looking forward to this leafy mattress
(Unreiking is the reverse of another esoteric exercise, reiking, whereby . . . well, leaves are raked up into plastic bags.)
Some people have too many leaves or otherwise don’t want them around. I have too few leaves and have use for them. By unreiking, the leaves get spread beneath my berry bushes, grape vines, and pear trees. These leaves feed bacteria, fungi, and other soil microbes, which slowly rot down the leaves to enrich the ground with nutrients and add organic matter that helps the soil hold both moisture and air.
Ahhhhhh
After doing this autumn after autumn for many years, the ground beneath these plants is as good as any agriculture soil in the world.
A Gardener’s, Farmdener’s, and Farmer’s Friend, Reconsidered
Our forest soils are similarly enriched, though to a lesser degree, with each autumn’s leaf drop. But change is under way, and the culprit is the earthworm.
Backtrack to about 12,000 years ago; that’s when the last glacier receded from the northern parts of the U.S. The glacier froze, compacted, churned and moved soil everywhere north of New Jersey, the upper parts of Pennsylvania, Ohio, Indiana, and Illinois, and parts of Wisconsin and South Dakota. Most of North Dakota was also enveloped by the the glacier, as well as, moving further west, the northern parts of the northern most states. In so doing, it killed off any native earthworms.
The still existing native earthworms to the south could have migrated back up here, but they move very slowly. Earthworms’ top speed is estimated at less than 6 yards per year.
Here, north of that line of glaciation, you and I do see earthworms in our soil. They’re not native; they arrived here nestled within pots of soil and organic debris, and as discarded soil ballast in ships, beginning in about the 17th century, with European colonists. And they liked it here.
More recently, those European immigrants — the worms, that is — were joined by worms from Asia.
Both species of non-native earthworms continue to spread in the soil of potted plants, in compost and leaf mulches, in home composting kits, and in discarded fishing bait (“nightcrawlers”).
Problem is that a few species of these non-native earthworms are very good a decomposing the leafy mulch that blankets forest floors. The blueberry, mountain laurel, rhododendron and other shrubs and ground covers in our forests thrive in that leafy mulch. The action of these non-native earthworms threatens to change the character of our forests.
Eek, A Snake Worm!
A number of years ago, my friend Sandy told me of strange happenings in her garden, of the abundance of worms and worm castings to the extent that the soil became so loose that her plants were flopping over. I pooh-poohed this report until a bit of research revealed this invasive worm issue.
I couldn’t offer Sandy any advice on what to do and, in fact, there’s no recommended way to deal with invasive worms. Discarding fishing bait at the end of a fishing day is one way these worms spread. (Sandy’s husband does fish.) They also can be spread in potted plants and in composts that were insufficiently heated and in mulches. (Uh oh; what about all my leaf hauling?)
For all the compost I make and spread, and all the leaves and other organic materials I haul here to the farmden, I come upon surprisingly few worms. One did catch my eye the other day, something about the way it moved and its robustness.
Crazy snake worm?
Could it be the European Lumbricus terrestris? Could it be the Asian “crazy snake worm”(probably Amynthas agrestis or A. tokioensis). Judging from the crazy way it moved and the pale collar (clitellum) circling its body completely, I’m guessing it’s one of the crazy snake worms.
Earthworms have always been a friend of gardener and farmer. Charles Darwin was a notable champion of them. After spending a lot of time on his belly in observation of these creatures, he wrote up his observations in a book, The Formation of Vegetable Mould through the Action of Worms. Darwin calculated that earthworms (probably Lumbricus terrestris) brought 18 tons of nutrient-rich castings to the surface per acre per year, in so doing tilling and aerating the soil while rendering nutrients more accessible for plant use. He wrote that “worms played a more important role in the history of the world than most persons would at first suppose.”
In our forests, European and Asian earthworms can eliminate leaf litter and change the soil composition to create conditions that favor non-native plants, decrease native plant biodiversity, and result in less understory vegetation. To the gardener and farmer, earthworms are a friend.
Greenhouse Happenings, Figs and Lettuce and . . .
Darkness Descending
Plant growth has come screeching (almost) to a halt. Lettuces just sit, hardly growing. No wonder, you are no doubt thinking. It’s getting colder and colder outside. I know that, but I’m writing about lettuces in my greenhouse. The issue isn’t lack of heat. It’s lack of light.
For more evidence that light is the issue, look to good vegetable gardens in southern Europe. In that mild climate, harvest from a well-planned vegetable garden continues year ‘round. But year ‘round harvest there takes planning — lack of light also makes for very slow growth over there in these darkest months. Unprotected plants survive because the winter weather never gets that cold over there. (And cool-season vegetables, such as spinach, radish, and turnips, that we plan for sprig or fall, are what do well in Mediterranean winters.)
My garden here in the Hudson Valley, at about the 42nd parallel, experiences winter day lengths the same as Rome, Italy or the island of Corsica — all on about the same 42nd degree of latitude. If lettuce plants grow slowly in Rome and Corsica, then the slow growth of lettuce in my greenhouse should come as no surprise. But it always does surprise me, and the brakes seem to start getting applied back in October, with full pressure about now.
All this came to the forefront of my attention back in 1992, when I read Eliot Coleman’s excellent book Four-Season Harvest. After highlighting the similar insolation of much of our “northern regions” with much of balmy Europe, he went on to describe various ways of protecting winter vegetable from our winter cold, which would kill most of them. Keeping the plants a bit warmer also gets them growing sooner once days become longer and brighter.
My goal, in the greenhouse, is to get a good share of the plants almost fully grown going into December. With lettuces, I try to plan to have enough of them to fill salad bowls through January and February, after which smaller plants are starting to grow fast enough to fill those bowls.
The 42nd Parallel
The reason Corsica and Rome remain relatively balmy all winter while winters here, with both locations at the 42nd parallel, get so frigid is that Corsica is bathed by the Gulf Stream, that warm mass of air that flows up from the Caribbean and across the Atlantic to wash over western Europe.
The warm touch of the Gulf Stream is lost as you move further east across Europe and into western Asia. Kazakhstan, parts of which also lie at the 42nd parallel, experience average annual temperatures from -60°F to 104°F!! The climate of nearby Turkey, whose north end touches that latitude, is moderated by the Caspian Sea. Moving further east to parts of Inner Mongolia, still within the 42nd parallel, winter temperatures might dip to -90°F.
A Greenhouse is not a Hothouse
If you were to join me in my greenhouse today, don’t forget your hat and gloves. The greenhouse is heated, but only minimally, enough to keep the temperature from falling below 37°F. That temperature provides a nice balance between energy use and reasonable year ‘round harvest. (Expotentially more energy is needed for incrementally increasing temperatures.)
Today is rainy and very cool, but not cool enough to kick on the greenhouse heater. So it’s pretty much the same temperature inside the greenhouse as outside the greenhouse — in the 40s. Most of what’s growing — kale, celery, mâche, claytonia, Swiss chard, mustard greens, parsley, and arugula — do fine with these conditions.
Leafy vegetables require less energy (i.e. sunlight) than do fruiting vegetables, so the low light is also fine to keep them happy even if only slowly growing, just as they would be planted (outdoors) in a garden in Corsica or Rome.
That’s also home to my baby, hardy cyclamens (about which I recently wrote), in a seed flat, until they decide to lose their leaves and go dormant. And two cardoon plants, also native to Mediterranean regions.
One Mediterranean plant that is very unhappy this year, even in the greenhouse, is fig. Figs are still ripening but, with the high humidity and low light, each is soon covered with fuzzy, gray mold. 
Roots of Rabbi Samuel fig, near the endwall, spread under the wall and outside the greenhouse, soaking up so much water that the figs split before ripening. Yet, a few fig fruits escape both afflictions and ripen to juicy sweetness.
I wonder if fig gardeners in the Mediterranean share my fig problems.
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. 
After 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.
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. 
For good contact, I pack the potting soil in with my fingers and the flat end of a 3/4 inch dowel.
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.)
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
