IS THAT VOMIT IN MY GARDEN? QUESTIONS WRAP UP SEASON
My neighbour, Laurie, had a garden question about her soil. “It looks like vomit except it is foamy and has grown overnight from the size of a quarter to the size of a salad bowl.”
I had this barf patch in my own yard last year and have seen it occasionally after a rainy spell in Calgary. The problem is slime mould and the cure is to do nothing.
Slime mould is a giant, quickly expanding amoeba-like cell. It grows on mulch and cow dung. Sometimes it comes in from a woodsy area and creeps onto your lawn overnight. Then it disappears.
Formerly considered a fungus, it is now grouped with protozoa, another type of microbe. And we want microbes. The more the merrier. They are primary digesters and turn raw materials into minerals.
Slime mould is an ambitious little microbe but it’s harmless. It will dry up and blow away in a few days. Sadly, Laurie scooped hers up and trashed it before I got back with my camera.
SPITTLE BUG
Gardeners are asking about spit on their plants. The problem is a small, soft-bodied bug, related to leafhoppers. And we never see the culprit, only the spit.
This “spit” is formed when air and liquids are pushed out with force from the rear end of immature bugs. And by immature I don’t mean they are acting badly, I mean they are nymphs and at this young age they use the “spittle” to hide, keep themselves cool, and stay moist.
Spittle bug foam and the bug hiding in it is easily washed off with water. Just aim your hose at it and blast away. Spittle bugs will moult this month and will be gone before August.
ODDLY TWISTED LEAVES
If you add compost or manure to your garden and your plants suddenly curl up or form distorted flowers it is neither a bug nor a microbe causing your problem. The problem could be a chemical called Clopyralid. This chemical, used to kill thistle and clover in fields and ditches, was banned from use on home lawns in 2002. So how did it get into your garden and will it stay there forever?
Clopyralid is legally sprayed on rural ditches and fields. When hay is cut and baled and fed to cattle, you can’t see the chemical within the plant. But like a drop of blue dye in a swimming pool, the quantities of this chemical needed to distort and damage our garden plants is very minute: in the parts per billion.
The chemical stays with the manure even after it’s composted. I first saw symptoms of it on Rudbeckia sold by a commercial greenhouse. My daughter saw symptoms of it on her potatoes. The bad news is this chemical takes 20-plus years to break down. So if you see the symptoms, garbage the plants, and be careful not to add it back into the compost.
Potatoes, tomatoes, sunflower, lettuce and peas are the most affected foods we grow.
SIGNS VERSUS SYMPTOMS
A stop sign makes you stop and take a look. A sign is something precise, that you can measure or see — like a slime mould or a glob of spit on a plant. A symptom is your impression of what you are seeing, like the distorted flowers after accidental contamination with Clopyralid. There is no smoking gun. When trying to solve a plant or garden problem, it is good to record a list of signs and symptoms.
A sign like powdery mildew — which looks like flour dusted on squash leaves — might be caused by a zinc shortage. Don’t try to add zinc to the soil if you recorded powdery mildew on zucchini last August. It takes too long to get minerals into the soil, processed through the bodies of microbes and sent back up into the plant. Because zinc is a small molecule easily absorbed through the leaves, I suggest spraying the leaves with a mild mix of Zinc Sulphate (ZnSo4), available as a vitamin from the drugstore. Mix a tablespoon of powdered zinc with a gallon of water just as you see the first symptoms of the problem. What are those first symptoms? Leaf edges curling under and browning.
If you get out there and start recording events in your garden this summer, you’ll definitely be able to put this puzzle together next winter when you re-read your journals.
You can join me online with your questions during my Facebook Live events on Monday afternoons at 4 p.m. MST. You can also connect with me online through my web page www. donnabalzer.com.