My garden was liberated yesterday, the soil freed at last. That’s when I peeled back and folded up the black tarps that had been covering some of the vegetable beds since early April. My beautiful soil finally popped into view.
Folding up tart
Covering the ground was for the garden’s own good. “Tarping,” as this technique is called, gets the growing season off to a weed-less start. The black cover warms the ground to awaken weed seeds. They sprout, then die as they use up their energy reserves which, without light, can’t be replenished and built up. (I first learned of this technique in J. M. Fortier’s book The Market Gardener.)

Tarping is very different from the much more common way of growing plants in holes in black plastic film, even if one purpose of the soil covering, in both cases, is to snuff out weeds. Black plastic film is left in place all season long, and then disposed of, usually in a landfill, at season’s end.

Tarping tarps might be silage cover material or — as in my case — recycled, vinyl billboard signs (black on one side). They are left in place for relatively short duration, after which time the ground can be exposed to natural rainfall and air, and is open for blanketing with compost and cover crops. After each use, tarps can be folded up and stored for re-use for many seasons more.

Prescription for Weed-lessness

Tarping is but one part of my multi-pronged approach to weed control, the others of which I detail in my book Weedless Gardening. 

My garden is also weed-less because I never, and I do mean never, till the soil, whether with a rototiller, garden fork, or shovel. Preserving the natural horizonation of the soil keeps weed seeds, which are coaxed awake by exposure to light, buried within the ground and dormant. No-till also has side benefits: preserving soil organic matter, maintaining soil capillarity for more efficient water use, and not disrupting soil fungi and other creatures.

Tilling does loosen the soil structure, but I avoid soil compaction by planting everything in 3-foot-wide beds, saving the paths between the beds for foot traffic.
Garden beds
Weed-lessness is also the result of each year covering the ground with a thin layer of a more or less weed-free mulch, just half inch to an inch thick depth. This covering snuffs out small weed seeds that might be present. Other benefits are insulating to modulate wide swings in soil temperature and softening the impact of raindrops so that water percolates into the ground rather than running off. 

What I use for this thin layer of mulch depends on what’s available, what I’m mulching, and, sometimes, appearance. Vegetables are hungry plants so their beds get an inch depth of ripe compost, which, besides the other benefits of mulches, also provides all the nutrition the vegetable plants need for a whole season. Paths get wood chips; it’s free, it’s pretty, and it visually sets off paths from beds. Straw, autumn leaves, sawdust, and wood shavings are some other materials that would work as well.

At the end of the season, beds that have been harvested but aren’t needed for autumn cropping, get a cover crop, which is a plant grown specifically for soil improvement.
Autumn cover crop
Cover crops provide all the benefits of mulches, plus looking pretty, sucking up nutrients that might otherwise wash through the soil in winter, and growing miles and miles of roots to give the soil a nice, crumbly structure. I plant oats or barley, because the plants thrive in cool autumn weather and then, here in Zone 5, are killed by winter cold sometime in January. The leaves flop down, dead, to become mulch, which I rake or roll up easily before it’s time for spring planting.Raking up oat cover cropClearing oat cover crop by hand

Another ploy for weed-lessness is using drip irrigation. Sure, I could get by without any watering here in the “humid Northeast,” but timely watering gets the most out of the garden. Drip irrigation pinpoints watering to garden plants rather weeds, which would, with a sprinkler, be coaxed to grow, for instance, in paths.

Weed-less but Not Weed-free

With this multi-pronged approach to weed-lessness, isn’t tarping like “taking coals to Newcastle?” No. I found that even after not tilling, mulching, using drip irrigation, and, especially, cover cropping, some weeds do a figurative “end run”and find their way into some beds. Especially, the last few years, red dead-nettle (Lamium purpureum). Purple deadnettleYes, I know the plant is pretty, provides early nectar for pollinators, and is edible. But its out of place in my vegetable beds. The tarp does it in.

No garden can be weedless. But mine has been weed-less for many, many years.


Plastic on My Bed?!

You’d be surprised if you looked out on my vegetable garden today. Black plastic covers three beds. Black plastic which, for years, I’ve railed against for depriving a soil of oxygen, for its ugliness, for — in contrast to organic mulches — its doing nothing to increase soil humus, and for its clogging landfills.Tarped soilActually, that insidious blackness covering my beds is black vinyl. But that’s beside the point. Its purpose, like the black plastic against which I’ve railed, is to kill weeds. Not that my garden has many weeds. But this time of year, in some beds, a few more sprout than I’d like to see.

The extra warmth beneath that black vinyl will help those weeds get growing. Except that there’s no light coming through the vinyl, so most weeds will expend their energy reserves and die. And this should not take long, depending on the weather only a couple of weeks or so.

So, first of all, I’m covering the ground for a very limited amount of time.

Furthermore, that the black vinyl is not manufactured specifically for agriculture. It’s recycled billboard signs, available on line from and other sources.  For larger scale use, farmers use the material sold for covering silage. 

Old billboard signs or silage covers also improve on black plastic mulch because they are tough. Each time they’ve done their job they can be folded up for storage for future use to be used over and over.

Heavenly Soil

Decades ago, I made a dramatic career shift, veering away from chemistry and diving into agriculture. In addition to commencing graduate studies in soil science and horticulture, I rounded out my education by actually gardening, reading a lot about gardening, and visiting knowledgable gardeners and farmers, including well-known gardener (and better known political and social scientist) of the day, Scott Nearing.
Scott Nearing's gardenI had just dug my first garden which had a clay soil that turned rock hard as it dried, so I was especially awed, inspired, and admittedly jealous of the soft, crumbly ground in Scott’s garden. What a surprise when someone who had worked with Scott for a long period told me how tough and lean his soil had been when he started the garden. A number of giant compost piles were testimonial to what it takes to improve a soil.

I thought of Scott and his soil as I was planting peas a few days ago. My chocolate-colored soil was so pleasantly soft and moist that I could have made a furrow with just by running my hand along the ground. For a long time I’ve appreciated the fact that the soil in my vegetable garden is as welcoming to seeds and transplants as was Scott’s.

And my dozen or so compost piles, inspired by Scott’s, are testimonial to those efforts. My compost pilesThe soil in my permanent vegetable beds is never turned over with a rototiller or garden fork; instead, every year a layer of compost an inch or so deep is lathered atop each bed, and no one ever sets foot in a bed. That inch of compost snuffs out small weeds, protects the soil surface from washing away, and provides food myriad beneficial microbes (and, in turn, for the vegetable plants).

All sorts of what I consider gimmicky practices attract gardeners and farmers each year: aerated compost teas, biochar, nutrient density farming, fertilization with rock dust, etc. Yet one of the surest ways to improve any soil is with copious amount of organic materials such as, besides compost, animal manures, wood chips, leaves, and other living or were once-living substances. A pitchfork is a very important tool in my garden.

Uh Oh, A Soil Problem

Not all is copacetic here on the farmden.

I make my own potting soil for growing seedlings and larger potted plants. It’s a traditional mix in that it used some real soil. Just about all commercial mixes lack real soil because it’s hard to maintain a sufficient supply that is consistent in its characteristics.

Early this spring, as usual, I sifted together my mix of equal parts compost, peat moss, perlite, and garden soil. This year, NOT as usual, germination of seeds and seedling growth has been very poor. Just today, I re-sowed all my tomato seeds in a freshly made mix from which I excluded soil.

I’m not 100 percent sure that the soil in the mix is the culprit, but it is suspect. I have a small pile of miscellaneous soil that I keep for potting mixes and other uses. Good and bad seedlingsRecent additions to that pile were an old soil pile from a local horse farm and soil from a hole I was digging to create a small duck pond. The latter was poorly aerated subsoil.

Seedlings are growing well in my new mix composed only of compost, peat moss, and perlite.

Dry, Wet, Bad, Good?

Some Bad

Wow! What a gardening year this has been. Looking back on 2018, it’s been the oddest year ever in terms of weather, insects, and disease.

After starting off the season parched, seemingly ready to go into drought, the weather in July did an about face. The rains began. Average precipitation here in the Northeast is about 4 inches per month. July ended up with about 6 inches, August saw 5 inches, September 8 inches(!), October 5 inches, and November 8 inches(!!).

All that rainfall brought humidity, which might have been responsible for my celeriac plants hardly growing, then rotting.

Celeriac in new home

Celeriac, early in the growing season, before the rains

(Perhaps not, because this was my third growing season of failure with celeriac.) I’m taking this as a celeriac challenge. Perhaps next year I’ll try them in a large tub where I can have more control over soil composition and moisture.

The humidity also had too many figs morph into fuzzy, gray balls as they softened and sweetened.

Tomatoes this year tasted very good, as usual, but yield was way down and too many showed some rotting areas. (In my experience, growing tomatoes under variable soil and weather at various locations around the country, their flavor is mostly a matter of genetics; a good variety tastes good everywhere.) Particularly irking was anthracnose disease, which often isn’t noticeable when fruits are harvested, but quickly shows up as round, sunken areas.

Onions suffered this season. Mostly they were stunted, and I’m not sure why.

Zucchini was a bust because the plants petered out from powdery mildew and vine borers just after midsummer. I usually circumvent these common problems with multiple plantings, starting new zucchini plants in early summer to replace the decrepit ones. I forgot to replant this summer (probably because I don’t like zucchini all that much anyway).

Medlar is an uncommon, very old-fashioned fruit that I’ve grown for many years. Although it’s gotten a bad rap for it’s ugly — to some people — appearance, the flavor is delicious, the soft flesh creamy smooth like apple butter with a similar flavor livened with vinous overtones. Medlar fruit in handUsually the plant is pest-free but a few years ago something, perhaps a fungus, perhaps an insect, started attacking it, leaving the flesh dry and crumbly. I have yet to identify the culprit so that appropriate action can be taken.Medlar pest damage

Some Good

Not that this past growing season was bad. I won the battle against soft scale insects (mealybugs) on my greenhouse figs, although their ecological niche was filled by just-as-bad armored scale insects. A close eye and an occasional spray of Neem oil kept flea beetles at bay from eggplants.

A couple of the same Neem sprays beginning in mid-September may have kept a new pest in the area, Allium leafminer (ALM, Phytomyza gymnostoma) at bay. Last year each of my near perfect-looking leeks revealed a rotted stalk as I lifted them out of the ground.

Allium leafminer

Allium leafminer

Then again, I did plant this past season’s leeks far from where the previous season’s leeks grew. Then again, the ALM flies can fly. Then again, maybe they weren’t here this year; perhaps the weather was not to their liking.

Nice leeks

This past season’s leeks

There was also no sign this past season of the white flies that decimated my kale the previous season.

Spotted wing drosophila (SWD), a species of fruit fly that has invaded the country relatively recently, did mostly ruin autumn ripening yellow and black raspberries. But little damage was suffered by my favorite (and perennially most successful) fruit, blueberries, probably thanks to some experimental traps developed by Peter Jentsch of Cornell University.

SWD trap

SWD trap

Peppers were even more of a success than usual, mostly due to my staking the plants. The only fault of Sweet Italia, my favorite variety for its early ripening, for its flavor, and for its good yields, is that the fruit-laden plants flop over under their own weight. Eventually, the small bamboo stakes I used proved only partially adequate; next year they’ll get the stakes they deserve.

I treated a few beds in spring to a relatively new method for weed control: tarping. Laying a sunlight-blocking tarp down on the ground for a couple of weeks or more in spring warms the soil beneath, stimulating germination of any weed seeds lurking there. The sprouting seeds are disappointed by the incessant darkness. They die. Timing, temperature, sunlight, and duration of tarping all play a role in this techniques effectiveness.

(Tarping is very different from using black plastic mulches. The latter are kept in place all season long, with garden plants growing in holes or slits in the plastic. Soil beneath the plastic can suffer from lack of air or, if not drip irrigated, lack of water. Also, the tarp — mine came from — can be folded up and re-used for many seasons.)

And finally, we were happy to find some assassin bugs and anchor stink bugs, Stiretrus anchorago, in the garden. Both are beneficial insects — yes even that particular stink bug.

Immature beneficial stink bug

Immature beneficial stink bug

Good Overall

All in all, it was a good season — as always. The secret is to grow many different kinds of plants. No season, no matter what the weather or pests, has ever been bad for all plants.