This week on Their house, my garden, we draw the battle lines when it comes to bugs and give tips on managing the baddies.

If you haven’t had the pleasure of meeting an entomologist, I would recommend it. I’ve chatted to one who stopped during a safari in Africa to watch a dung beetle crawl out of a pile of dung. It was the highlight of her trip, despite complaints from two French tourists in the backseat. 

I’ve met another who confessed that her workmates tease her for smelling like cabbage. She has lovingly reared a diamondback moth colony for 30 years, and because it must not be contaminated by pesticides, she has become an avid spray-free cabbage farmer. Perhaps it is coddling, perhaps it is science, and perhaps it is both. I’ve learned a lot from bug obsessives about which bugs to blast into oblivion and which to lure into the garden with sweet, sweet nectar. Let me name and shame them for you to avoid garden disasters.

Foes

Despite the undying love of the entomologist above, diamondback moths are not a gardener’s friend. They are a pest of all brassicas. If you see a small moth about one centimetre long with a light-coloured ridge along the back of its wings (that doesn’t really look like a diamond at all), it’s come for your broccoli or cabbage. If you see a white butterfly with one or two black spots on its wings, it may or may not be all over. 

Then there are the pests that come in the night. Snails can leave behind nothing but a trail of slime where there once were loved seedlings. That’s the thing about plants: humans are far from the only animals to find them delicious. Plants are the foundation of the food chain. They produce, and the rest of us just consume or decompose.

“My garden is an ecosystem,” so the twee gardening poster reads. People with big, lush gardens often like to tell you that they do not use pesticides. They think their full vege beds are proof that not using any is good and that pesticides are evil. What they really prove is that they are rich in vegetables and so can afford to give some away to bugs. 

You and I, on the other hand, are currently vegetable poor, and cannot afford to spare a leaf. Feeding a hungry caterpillar this early in the season may mean that our seedlings die. Bugs will eat every last leaf on a little seedling and leave them with nothing to capture sunlight with. Then we are left only with sad stems as tombstones of what could have been. 

I want to save you from the tragic fate of looking at slime where there should be seedlings. Reject suffering. Buy a box of Blitzem. Sprinkle it around all your seedlings. Ta-da, no snails and no slugs. It only needs to be done once a week, while your plants are small and vulnerable. When they’re big and strong we can stop, let our slimy foes have a few nibbles, and tell people we are into permaculture. 

If you really can’t handle doing this to your beautiful garden, you are going to have to stay up late and hunt. When it’s properly dark, go outside with a torch, find slugs and snails, and stomp them viciously under a chunky boot. They need to be more squished than you think to die. I have also witnessed a flatmate make beer traps for snails, but my humble opinion is that this is not a good use of beer and it didn’t really work.

Flying foes are a bit tricker. We can’t just spray the outside air with pesticide, and they’re not so easy to hunt. Which brings me to…

Friends

Entomologists call good bugs “biological control agents”, which summons images of bees in wrap-around sunnies holding black leather briefcases. I already know you like bees because they are pollinators, but I did once meet someone over 30 at a barbecue who didn’t really know what this meant in terms of growing vegetables. So let me explain the flowers and the bees.

Let’s take a tomato plant. First your seedling is going to turn into a little bush or tree vine. Then little sprigs of flowers will appear among the leaves. The flowers are yellow and very cute. This attracts the bees, who collect pollen and fumble the flower’s reproductive bits in the process; fertilising the flowers. Only then will a tomato grow. Flower + bee = tomato.

Being sexy does not amount to being a biocontrol agent, though. This is a different role that bees and wasps have in the garden. In short, they attack, eat and lay their eggs in many foes. Friend bugs are the reason we don’t want to use too many pesticides in the garden. We don’t want to kill these diligent buzzers with their briefcases. Instead, we want to plant flowers to attract and fairly compensate them. As we will find out next week, there are other compelling reasons to grow flowers, too.

It is hard to counter the argument that worms are gross. They writhe, have no face, and are sticky. Also, because they have no limbs, they seem pathetic and useless. People braver and more altruistic than me move them off hot concrete paths on sunny days. Worms are kind of like microbes and fungi: they break things down and their poop enriches the soil. There should be a whole writhing mass of them in your compost. If there’s not, it might be too dry (hose it) or you might want to stop putting in acidic things like onions and citrus and see if any turn up. Worms are so good that people even pay money for them.

Still, I reckon worms are the reason people wear gardening gloves. There is no shame in this and I recommend it if you are afraid of any bug, because you will be encountering them. I too was once fearful of bugs; so fearful, in fact, that when a worm was thrown at me I had the unfortunate reaction of peeing my pants at school and having to borrow shorts from the lost property box. Now I’m pretty sure there are spiders living in my gardening gloves and here I am, spreading worm propaganda. 

Top tip: If you think bugs are gross, fair. Get some gardening gloves.

Task for the week: Sprinkle Blitzem.