Organic weedkiller between row of pear trees

SOAP UP

Plus Ça Change . . .

In gardening as much as anything else “the more things change, the more they stay the same.” In 1845, Andrew Jackson Downing, famous horticulturalist (and native son to New York’s Hudson Valley) that a “wash of soft soap is very good for many purposes . . . penetrates all the crevices where insects may be lodged, destroying them.”Vintage ad for sprayer

Savvy gardeners were using soap sprays even back in the 1700’s, and they were continuing to do so right through the beginning of the 20th century. Read more

Ladybugs on leaf

WHERE’S HOME?

Migration

“Ladybug, ladybug fly away home…” Whoops, she did! And she’s made my home, and perhaps your home, her home. With spring just around the corner, she’s awakening and coming indoors.

Ladybugs are such lovable creatures that we — or I, at least — can’t call them a pest even when they act like one. Just now they’re creeping on windows along with cluster flies, also benign creatures but “pests” not at all welcome in my home. Ladybugs do get even peskier indoors: I occasionally find them marching across a pillow just before I lay down my head or scuffling along the edge of a teacup just before I take a sip.Madonna in the Meadow

It’s not your imagination that the annual ladybug migration indoors has increased from years’ past. Read more

CAT NIPPING, NOT SO GOOD

A Nonsymbiotic Relationship

Cats like houseplants, but houseplants don’t particularly like cats. Or, at least, cats don’t do houseplants any good.

Cat at window

Take my ponytail palm, for example. My cat is an outdoor cat, but I know if she came indoors, what a grand time she’d have jabbing her claws playfully at the ends of the ponytail palm’s wispy leaves. She’d do the same for my orchid’s flower stalk, now weighed down with a row of delicate blooms. Either plant would emerge from such play worn and frayed.

There’s not much you can do once a plant catches your cat’s fancy, except Read more

Yellowjacket

A GARDEN PEST OF HUMANS

Yellowjacket Frenemies

Not all garden pests attack plants. One pest, not of plants, that especially bugs me around this time most years is yellowjackets. Yellowjackets can be worse than irksome; they can be deadly to people allergic to their sting.

Whether deadly or just irksome, yellowjackets are amongst the orneriest of creatures. They are aggressive and, unlike honeybees, don’t have to stop after one sting. Burying its stinger in your arm has no effect on a yellowjacket’s mortality, so it can do it again if it so pleases or go on to seek out other victims.Yellowjacket

As with all of Mother Nature’s creatures, yellowjackets are not all bad — even from the biased viewpoint of us humans. Read more

Rhizoctonia damping off

DAMN-PING OFF

Worse than Roman Warriors

I made my first gardening enemies decades ago, within a few weeks of starting my first garden. Not other gardeners but — and perhaps you also have crossed paths with them — with Pythium, Rhizoctonia, and Fusarium. I quickly learned that they were, or should be, hateful not only to me but to all gardeners.

Pythium, Rhizoctonia, and Fusarium are not ancient Roman warriors; they are fungi and, worse than Roman warriors, they lurk everywhere. When they, or one of them, gets the upper hand they cause damping off disease.Beet seedling damping off

Let’s return to my first garden: At the time, decades ago, I was living in a relatively dark apartment, a converted motel room, and was eager to start my first seedlings. I sowed all sorts of seeds in peat pots, stood them in a little water, then crowded them together on all the shelf space that could be mustered.

Young sprouts never appeared in some of the pots. In others, seedlings emerged, then toppled over, their “ankles” reduced to a withered string of rotted cells unable to support the small plants physically or physiologically. Read more

Spreading wood ash

OCCULT PRACTICES?

Potash Kalium Connection

I wonder if my neighbors suspect that I’m engaging in some sort of occult ritual as I take rounds through the farmden followed by puffs of grey smoke. Perhaps I’m entreating tiny gnomes living within the soil to keep weeds at bay next season? Or begging garden gremlins to make my soil fertile? No, and again no! I’m merely spreading wood ashes.Spreading wood ash

I must be careful with my terminology: I’m not dumping wood ashes; I’m fertilizing my soil with wood ashes. Wood ash is a rich source of potassium, a nutrient required by plants in amounts second only to nitrogen. Potassium helps build strong stems and helps plants resist disease. It also regulates the opening and closing of stomata, the tiny pores in leaves through which gases pass for photosynthesis.

The close connection between potassium and wood ash is reflected in a traditional source of, and the root of the word, potassium — “potash.” Read more

Peony with powdery mildew

FOR THAT UNWELCOME MEDITERRANEAN LOOK

One Name for Many Diseases

The powdery white coating I notice on leaves of my peony and lilac plants gives them a very Mediterranean look. Not attractive, though, at least to me, because that’s a sign of a disease, appropriately called powdery mildew. If I look around the garden, the disease is probably showing itself, or soon to do so, on a wide variety of plants, including phlox, zinnia, squash, gooseberry, and many more. (This blog post is excerpted from the chapter about plant stresses in my book The Ever Curious Gardener: Using a Little Natural Science for a Much Better Garden.) Peony with powdery mildewEven though powdery mildew is pretty reliable in showing up each season on certain plants — this is important! — the disease doesn’t necessarily spread from one kind of susceptible plant to the next. Many different fungi are responsible for the disease we collectively call powdery mildew, and each of these fungi have specific plant hosts. Thus, the fungus that causes powdery mildew on lilac (the fungus is Microsphaera alni) cannot cause powdery mildew on rose (caused by the fungus Sphaerotheca pannosa). Read more

Slug

PESKY CREATURES

Vegetables are Easy, But . . .

I consider vegetables generally easy to grow, especially if you grow lots of different kinds. If one kind does poorly one year, there are lots of other vegetables in the garden doing well, and there are other years.View of north garden

Still, vegetable — and flower — transplants are especially apt to suffer attacks from three pests this time of year, each leaving a telltale clue to its presence or handiwork. Stems might be chopped off at the soil line. Leaves might be chewed. Or leaves might be shot full of tiny holes. The culprits? Respectively: cutworms, slugs, and flea beetles.

All three culprits have cosmopolitan tastes, attacking practically any transplant you set out. Fortunately, these pests can be controlled to some degree without toxic (to you, and nontarget creatures) sprays, usually without resort to any sprays.

A Few, But Deadly, Bites

Cutworms take only a few bites out of new transplants, which would not be reprehensible if those few bites were not at ground level. Seedlings topple and, because they are just seedlings, never recover. Cutworm damageThe damage should not be confused with damping-off disease, which is a fungus that also attacks at the soil line, but only afflicts newly emerged seedlings. To make sure, scratch with your finger in the soil near the toppled plant and look for the bugger. Then squish it.Cutworm and broccoli

Cutworms are easily repulsed with some sort of barrier, such as a cardboard collar around each plant. Toilet paper tubes cut a couple of inches long are convenient for this purpose. Surround each transplant and press the collar a half-inch or so into the soil.

Before a cutworm takes a bite of a plant, it wraps its body around the plant’s stem to make sure the stem is tender enough to bite into. Once stems of vegetable and flower transplants toughen, cutworms leave them alone.

I used to fool cutworms by sticking one toothpick in the ground right up against each of my transplants. It worked. The insects think they are embracing small, woody-stemmed trees and leave the young plants alone.Cutworm protection with stick

Another method to foil cutworms (which I have not tried) is to trap them in foot-deep holes, made with a broom handle or an inch-thick dowel. As daylight approaches, the cutworms climb into these holes for shelter. What the cutworms do not realize is that they are incapable of ever climbing back out.

The life of the cutworm is not easy: this pest is also food for birds and ground beetles, and is parasitized by certain small wasps.

I have to admit that I haven’t used any of these cutworm control methods for years and years. I never see cutworms or their damage anymore. I’d like to think that it’s evidence of my having a green thumb, but much more likely are the robins and morning doves that I see patrolling my garden early every morning.

Slimy Slitherers

Moving on to slugs . . . these creatures love wet weather. Slugs slither around at night and by morning their presence is made known by the shiny trails and ragged leaves they have left. Here in the Northeast, they are up to a couple of inches long. In other parts of the country, they get as large as a half a foot or more long.Slug

Slugs don’t like anything sharp or caustic rubbing against their slimy bodies, so if you sprinkle a circle of sharp sand, diatomaceous earth, or woodashes around your plants, a slug will think twice before crossing this barrier. Unfortunately, these barriers must be renewed after rains, which is when slugs are most active.

You could take a flashlight into the garden at night and sneak up on slugs while they are at work. They are slippery to handpick, so take along a saltshaker. Sprinkling salt on them will kill them. It’s gruesome to watch, but very effective.

Beer is a somewhat effective poison bait for slugs. Put some beer — Budweiser is one of the best — in a shallow pan or cqn and sink it into the ground so the lip is about one inch above ground level. Almost immediately slugs will start inching to their demise.

A bait containing iron phosphate is very effective agains slugs, and considered nontoxic to just about everything else, including humans.

No need to open a fresh bottle each night, for slugs are happy even with stale beer. Some gardeners report good results with only yeast plus water. You might need lots of traps because slugs won’t “hear” the siren song of beer beyond a few feet.

A Different Kind of “Flea”

Flea beetles, which perforate leaves with small holes, are the most difficult of the three pests to control without pesticides. You may not notice the beetles because they’re only a couple of millimeters long and hop away when approached. Fleabeetles on eggplant

Lawrence D. Hills, in his 1974 book Grow Your Own Fruit and Vegetables, describes a contraption he put together himself. It looks like a high-riding skateboard, with a long handle at the top of the middle and a horizontal metal wire down across the front of the board. He tacked flypaper on the underside of the board. (Tangletrap© spread on the underside would work as well, or better.) As you push this contraption over a row of plants, the wire disturbs each leaf — and the flea beetles. Flea beetles hop away when disturbed; for these flea beetles, it’s their final hop as they get stuck on the flypaper.Flea beetle trolley

Predatory nematodes, which you can purchase, might also limit flea beetle damage by attacking eggs in the soil. I added predatory nematodes that have the potential to perennialize to my soil, available from the Shields Lab at Cornell University. These have been shown to be effective against some pests that spend part of their lives in the ground. Patience is needed as their numbers multiply.

Flea beetles are especially fond of cabbage and its kin, as well as spinach, beets, and potatoes. They’re mostly a problem on my eggplants; actually, just about everybody’s eggplants. I and many other gardeners and farmers thwart them, by covering plants with a barrier of a “floating row cover.” These lightweight materials, made from spunbonded or woven synthetic materials, are permeable to water, air, and sun, but impermeable to insects. The barrier must be in place before seedlings emerge or right after setting out transplants.

Sometimes it’s appropriate just to ignore pest damage, for awhile, at least. Small transplants often outgrow flea beetle or slug damage, provided the plants are growing rapidly enough and the pests are not too many or too hungry.Garden view

MORE OF MY FAVORITE TH . . . GRAPE VARIETIES

The Birds and the B . . . Vespids

Hot and dry. What great summer weather it’s been here for grapes. Most years around this date, I’d go out every morning and pick bunches for fresh eating, continuing to do so for weeks to come.Basket of grapes

Alas, where there are grapes, you’ll find the birds and the be. . . vespids (the family of wasps and hornets, not bees). No raccoons or foxes, here on my grapes, at least. Here you’ll also find paper bags stapled around about a hundred bunches.

The bags are meant to protect the enclosed bunches from birds and insects. This year was a first: Thirsty birds pecked holes in the bags through which they could reach, then peck at the grapes hanging within. By my estimate, about three-quarters of the bagged bunches suffered damage or were finished off in toto. 

In addition to the damage inflicted by the birds, the resulting holey bags provide easy entrance to wasps and hornets, who further tear up the bag and finish off the fruit repast started by birds.

Read more

COMPOST TEA REVEALED

First Step, Identification

A few years ago I went to a nearby permaculture convergence. (Actually a “permaculture conference; those people have the best terms for what they do). I’ve grown plants in what I learned was a permie way for many decades, so I’ve been accused of being a permaculturalist. I was even invited to do a presentation and host a farmden tour for the convergence.

While there, I had the opportunity to attend a lecture by someone who has been billed as the diva of dirt, or, at least, of compost tea, specifically aerated compost tea (ACT), Dr. Elaine Ingham. You’ve never heard of ACT!? It became the hot, new thing years ago, perhaps still is, as an alleged cure for poor soil and plant pests. I’d been skeptical and thought that hearing and speaking to Dr. Ingham in person could entice me into the fold.Making compost tea

  Dr. Ingham showed myriad images of fungi, nematodes, and other creatures that you might find in compost piles and teas. We saw many “bad guys” that lurk in poorly aerated composts and teas. The “bad guys” are bad, she asserted, because they release toxins into the soil and puff away valuable nitrogen, sulfur, and phosphorus in various forms as gases.

  Dr. Ingham suggested monitoring our compost piles and tea happenings by purchasing a microscope and, with the help of her workshops, identifying resident microorganisms. Hmmm; interesting, but is it really necessary for a green thumb?

  While the panoply of microorganisms discussed was impressive, I contend that even a well-aerated compost pile or tea is bound to have some poorly aerated pockets. It’s not a “bad guys” vs. “good guys” situation, but a question of generally favoring an excess of “good guys.” Also, once compost is spread on the ground, the large surface area presented is going to tip the balance even more in favor of aerobic conditions.

To identify what organisms are in a compost pile, you have to get them out of the pile and onto a microscope slide. Easy. Just soak some compost in water and strain it. Or use a compost teabag. But wait! Is that really the spectrum of microorganisms that call that compost home? Not necessarily. What are staring up at you from that microscope slide are creatures that can be leached most readily into water. What you see also might depend on how long you steeped the teabag and who can squeeze out into the water through whatever size holes are offered by the strainer or the teabag.

Will Compost Microbes be Happy Far from their Compost Home? More fundamentally, I question basic assumptions underlying the use of compost tea. Even if you have beneficial organisms in hand (figuratively) and sprinkle them on the ground, they’re bound to expire unless the environment is suitable. Microorganisms in the tea might have enjoyed life within the dark, moist innards of a compost pile; the soil environment ain’t nothin’ like home for them.

Spraying ACT or any compost tea on plant leaves should likewise have little or no effect on plant diseases; again, conditions on a leaf surface aren’t conducive to their survival. In the evolutionary scheme of things, why would a microorganism that thrives in the dark, moist, nutrient-rich innards of a compost pile survive on the sunny, dry, nutrient-poor surface of a plant leaf, let alone provide any benefits?Spraying plants

Over the last few decades, people have spritzed plants and sprinkled soils with compost tea, looking for effects such as improved soil structure or drainage or increased plant resistance to pests. Independent well-designed, vetted studies do not generally support claims made for compost tea.

True, there are some studies that show some benefits. I contend that if you spray just about anything on a plant leaf and have enough plants in the study along with sufficiently detailed measurements, some statistically significant effect might be noted. But every statistically significant effect isn’t also biologically significant. And looking over a number of studies, some few show a benefit from compost tea, many demonstrate no effect, and for a number of them, the effect of compost tea is detrimental.

Soluble nutrients do leach out of a compost teabag into water. The resulting compost tea, then, becomes a liquid feed for plants, effective either poured on the ground or even sprayed on leaves. So there can be some benefit from compost tea, a nutrient effect, not a microbial one.

Bulk is Good

Except in special situations, soil environments naturally host microorganisms that thrive best in them. A similar situation exists with earthworms. Years ago, perhaps still, advertisements in the back pages of gardening magazines would offer earthworms for sale. The reasoning went that good soils are teeming with earthworms, so purchasing and importing these creatures to you garden will make your soil better. Not true. The earthworms will die out if conditions and food are not to their liking. The same goes for microorganisms.

(An example of an exception to what I wrote in the previous paragraph is a study that was done in Puerto Rico back in 1950. THE USDA was trying, with little success to introduce a more useful, but non-native pine, to the island territory. Mycorrhizae are fungal symbionts that infect practically all plants; the fungus gets some foods manufactured by the plant in return for moving more nutrients and water to the plant for improved growth. The appropriate fungal symbiont was lacking in Puerto Rican soils. After inoculating plants with an appropriate fungus, the inoculated, introduced pines grew six times more than their introduced brethren that had not been inoculated.)Compost being shovelled

Except in rare situations, as in the example above, earthworms, microorganisms, and other creatures generally inhabit environments most congenial to their flourishing. Perhaps not enough of them, and what they really need is food to give their populations a boost, and food means some form of organic material. That is, bulky organic materials, such as compost, manure, leaves, and straw.

  Good gardening comes form using a pitchfork, not an elixir. Does anybody still make and use compost tea?