Last Summer, for instance, I was plagued with a gardener's worst nightmares. Blight ravaged the potato barrel (which I could live with) but then spread to my beef tomatoes. It was a real pain because the damage was hard to spot. A couple of leaves browned, but nothing that seemed serious. Then after some Summer rain and spore-friendly humidity, the green tomatoes turned brown rather than red. I hastily turned what I could into chutney then disposed of everything as I could sense this was the only way to win the battle against Phtophthora infestans. I'm not sure where the victory here is, but the chutney was delicious - every cloud, eh?
But the real plague last year wasn't a disease but a pest, and the critter in question was the fungus gnat or Sciarid fly. I love all things living and don't generally squash bugs or slice slugs, but I make an exception for the fungus gnat. It's a real horror; it survives as eggs in infected compost, then hatches out as tiny white maggots which grow into slightly larger tiny white maggots the more tender young roots they eat. They pupate into small black flies that are attracted to the smell of compost and decay (hence fungus). Their ditsiness would almost be endearing if it weren't for the fact they are such prolific breeders and have a lifecycle so short that they can progress from egg (through maggot) to breeding adult again before you can say, well, 'fungus gnat'. In short, the last thing you want is to see, through a haze of ditsy black flies, is a wriggling crowd of tiny maggots in the soil around your prize onions.
Everything I had grown indoors on a windowsill last year was affected, and when these seedlings were transplanted to the greenhouse, the swarming mass soon unleashed their weapons of predation and fecundity on everything else. They were indifferent to a homemade deterrent made from mint tea (I blame the internet for this suggestion); they were less keen on the garlic and chilli spray I made, but not in a sufficiently lay-down-and-die manner that would have solved the problem.
I resorted to an expensive nematode - a packet of microscopic wriggly things that kill the Sciarid flies at pupal stage, and break the lifecycle. That's the theory at least; when your nematode has a pretty short shelf life and you still have a host of fungus gnats floating round ready to infest the clean compost, you're fighting a losing battle. My only option then was yellow sticky traps, pieces of paper which you hang above the plants and which the Sciarid flies stick to and can't get away from. These may have reduced the population slightly, skimming off a couple of high-fliers, but 90% of Fergie Fungus-Gnat's friends are still able to hum around safely and spread the love. Also, everything sticks to the sticky traps, including hair, if you're not careful!
So, you can imagine my horror when, early February this year, I spotted the first wriggly maggots on my newly germinated onions. To add a little back-story, last year I had started my onions around New Year 2013; the long growing season, a good warm bed, and a liberal hand with some root veg fertiliser had stolen them the top onion prize at the local Flower Show in 2014.
So this year, I started a new course of action against the nefarious gnat. I wanted to catch the blighters before they metamorphosed into a prolifically reproducing pest, so thought I would make life as hard as possible for the larvae. I removed heat (turned the radiator from low to off), so the trays were less than 18°C (if you're a fungus gnat, anything higher tells you to get out of bed and get nibbling). Then I completely parched the soil except for a well directly around the onion. I let this dry out too, but not for long enough to wilt the seedling. After a fortnight of keeping the onions near the edge of enforced drought, I noticed that my wriggly friends had vanished. Not a single critter to be found on the soil surface or anywhere. I gingerly rehydrated the soil, but kept it cool and a little on the drier side - y nada. Tumbleweed.
As I say, it's a subtle victory, and we've made it through to April without the dreaded F-G raising its ugly head again. My onions are still on the weedy side - but they're slow growers anyway, until they get free run. Once the conditions are right, these babas will go outside and should hopefully swell to emulate the victory of 2014!
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