Aphids and Squash Bugs, and When to Ask the Extension Office
Okay. New module. We're past frost, past the worst of the heat management, and now we're into the part of the season where things are actually growing well. Which means bugs have found them too. That's just how it goes.
I want to keep this lesson narrow on purpose. There are a hundred pests that can show up in a Utah County garden and I am not going to pretend I can identify all of them for you, because I can't. What I can do is teach you the two I actually know cold, aphids and squash bugs, and then tell you exactly what to do with everything else. That last part is the more useful skill, honestly.
Aphids
Aphids are the little soft-bodied bugs that show up in clusters on new growth, usually the undersides of leaves and along stems near the tips. They're green or yellow or sometimes black, small enough that you might see the damage before you see them: curled leaves, a sticky film on the plant called honeydew, sometimes a black sooty mold growing on that honeydew.
They're slow. They don't fly off when you touch the plant, they just sit there sucking sap. That's actually good news for you, because it means you can deal with them without anything fancy.
Here's what I do:
- Spray them off with water first. A firm spray from the hose, focused on the undersides of leaves, knocks a lot of them off and they don't climb back up fast. Do this in the morning so the plant dries out before evening, especially with our dry air, standing water on leaves overnight isn't usually the problem here that it is in wetter climates, but there's no reason to test it.
- Check daily for a few days after. Aphids build up fast. A few on a leaf tip on Monday is nothing. The same few, unchecked, is a colony by Friday.
- Insecticidal soap if the hose isn't cutting it. You can buy this or make a weak dish soap and water mix, but go easy, too strong and you'll burn the leaves. Test on one leaf first.
- Ladybugs are your friends. If you see ladybug larvae on a plant with aphids, which look nothing like ladybugs, kind of like tiny alligators, leave them alone. They're doing your job for you.
Brittany texts me photos of aphids pretty regularly now, always some version of "is this bad." Usually the answer is no, not yet, hose it off and keep watching. I like getting those texts because it keeps me honest about what I actually know versus what sounds like I know it.
Squash bugs
These are the ones that make people mad. Squash bugs go after squash, pumpkins, and zucchini, and they multiply like nobody's business if you let them get ahead of you.
Adults are grayish brown, about five-eighths of an inch, kind of flat and shield-shaped. They hide at the base of the plant and under leaves. The eggs are the giveaway: small bronze-copper clusters on the undersides of leaves, laid in neat little rows. If you find eggs, scrape them off into a jar of soapy water. Don't just knock them to the ground, they'll survive that.
The nymphs, the babies, are grayish with dark legs and they cluster together. Squish them or drop them in soapy water. I know that sounds unpleasant. It is a little unpleasant. Wear gloves if it bothers you, but do it, because a light infestation you catch early is a ten-minute job and a heavy one is a plant you lose.
Adults are harder to kill with soap sprays, their shell is tougher. Handpicking in the morning when they're slow is honestly the most reliable method I've found. Check the base of the plant and the underside of leaves, drop what you find in soapy water, and do it every few days once you see any sign of them.
What I don't know, and what I do instead
Past those two, I take a photo and I say I'm not sure. That's the honest answer for me every time. I know what a squash leaf looks like well enough to draw it, badly, in my journal. I don't know every pest that'll show up on it.
This is where the extension office earns its keep. Utah State University Extension has a Utah County office, and they will identify a bug or a plant problem from a photo, often faster than you'd think. That's their whole job. Use it. There's no shame in sending them a blurry phone picture of something chewing on your bean leaves and asking what it is. I do it. Debbie's opinion on this one: guessing wrong and treating for the wrong pest wastes your time and sometimes hurts the plant worse than the bug would have. A five-minute email or call is cheaper than that.
The other thing worth saying: not every bug in your garden is a problem. Most of what you'll see out there is neutral or actively helpful. The instinct to spray everything that moves is a bad one. Identify first, then decide if it's worth acting on.
The upside of all this
I'll say this because it's easy to get discouraged staring at aphids on a tomato leaf. My first real win in this garden wasn't tomatoes at all, it was a row of bush beans that just took off, more beans than my family could eat in a week. I hauled grocery bags of them over to Brittany and Bailey's and felt pretty smug about it, not going to lie. Pests are part of the deal. So is that.
Before next time
Walk your garden this week and actually flip a few leaves over, especially on squash and anything with new tender growth. You're looking for eggs, clusters, curled leaves. Takes five minutes and it's the whole game.
- D