I recently noticed the yellowing of some leaves in the greenhouse and a couple of plants dropped their leaves. I’ve been pretty attentive so wondered what might have gone wrong. Nutritionally, the plants should be fine, so I’m going to rule out nitrogen deficiency for now, I think, although I know this is a common problem. And they’re watered fine, not too much, not too little, which is probably the most common problem. So next I checked for pests. The following are the most common greenhouse villains prowling about our garden.
Slugs. The dryness, the daily check around the corners of the greenhouse, and the strulch have been helping against slugs. I also copper-taped the table legs of the bench, which has about 10 peppers on it, just as an extra preventative. So far (touch wood) the only one who has been slugged was one I did not strulch or protect properly one night. But overnight the slugs and snails have decimated other seedlings outside and I’m finding one or two in the corners of the greenhouse each morning, which I toss as far into the woods as I can. I know snails have that homing instinct, but I’m hoping the greenhouse isn’t really home and that there’s so much vegetation between where I throw them and here that they’ll get distracted on their way back.
Aphids. In previous years these have been a pain but I’m checking the leaves regularly and so far they haven’t been an issue. I have seen them around the garden and they’re bound to get in at some point but hopefully I’ll catch them early enough that they don't become a problem. I’m checking the undersides of the leaves for signs every few days and basically taking off anything I find there.
White fly. These still have potential. I’ve seen them on the horseradish and the basil plants around the back of the house but so I've found just two in the greenhouse. (They were evicted roughly.) I think I might need to take daily care of the horseradish as he’s hosting just about everything at the moment - slugs, snails, caterpillars, some other kinds of eggs, and white fly.
Red mites. These are covering some of the pots. I think they’re red velvet mites, which are harmless at worst, maybe even beneficial, but online information is so muddled and intertwined with (harmful) spider mites and US species that I’m not 100% sure.
Fungus Gnats. These were a nuisance in the house late winter and early spring. They come from the soil being damp and appear to be unavoidable. I understand they’re not the end of the world but large quantities of larvae growing and nibbling in your seedlings might become a problem. Mostly they’re just annoying in the house. They haven’t been such an issue in the greenhouse, although in the past few days with this wet weather they seem to be blooming again.
Ants. People often say these are harmless to gardens and plants and do a nice job of rounding up aphids, but in the greenhouse I find their nests undermine the roots and the plants have suffered. We’ve got at least three species around the garden - red, yellow and black - and we have green woodpeckers who nest every year in the area and bring their young to feed on the ants in the garden, so it’s only in the greenhouse they can be issue. Two green woodpeckers were in the garden yesterday yaffling about for ants.
In all honesty, most of these bugs will get squished if I find them, except the ants, and if I get in early, as I have been so far, it shouldn’t be a huge job. But having had a look for pests, I now think the issue has been the weather. We’ve had such a mixed month. There were a few scorching days when the temperatures in the greenhouse were into the high 30s, and then at night they’ve been regularly down to 10C. Right now it’s dark and wet and has been for a few days. The peppers that have been left outside (mostly Rocotos) have had a good watering.
It’s the Jalapenos and the Zebrange who are feeling it worst. They seem to be very sensitive to the weather. This is a part of UK growing we have to consider, I guess, when we choose which peppers to grow, and in Cornwall that combination of wet and warm can benefit some plants but also lots of pests. I’m keeping an eye on which peppers suffer worst. I hadn’t expected it to be the Jalapenos, I have to say. They were doing so well earlier in the year.
If anyone has had a similar experience with the Farmers Market Jalapeno variety I’d love to hear.
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