Slugs & snails
The first of these are easily kept under control with slug and snail bait. I’ve recently changed from the bait containing the chemical Methiocarb, to Quash, which is based on iron chelate, which is much softer on the environment and also provides some nutrition to plants as it breaks down. The key for effective control is sprinkling the bait before a bout of rain in spring and autumn, when slugs and snails are on the move looking for new grazing.
Pheromone traps are used for codling moth control, hung in early spring just before bud burst to trap randy males as they search for females. Obviously this won’t always be effective, as some boys will get to the girls before they get side-tracked. The next line of defence is to strip off and destroy (the mower works well) any infested fruit early, before the larvae mature and escape. Those that do escape can be trapped in bands of corrugated cardboard wrapped around the trunk in late summer, with a band of grease below to stop the larvae getting any further. Just remember to remove the band and burn or bin it over winter, otherwise you’re just supplying them with a lovely winter hideaway.
Passion-vine hoppers have very few effective natural enemies and explosive growth potential. The key is getting in early while they are still in the “fluffy bum” stage. Starve and smother these with neem and insecticidal soap sprays as soon as you spot them in the garden and then follow up with targeted spot spraying. Once they’ve matured into the delta wing stage, you’ve lost the battle, as these are very hard to control unless you use chemical warfare.
The newly introduced potato psyllid which devastates crops in the tomato family is next to impossible to control using any sprays. It’s a bit like the malaria of the plant world; you only need one of these pests injecting their disease infested mouthpieces into your plant for the plant to become infected, gradually decline and become a shell of its former self. I now cover any crops of tomatoes, peppers, eggplant and potatoes from mid-November with insect proof mesh. It’s a hassle, but worth it.
Green vegetable bug
The most effective control for green vegetable bug is the old two finger technique (no not that one, although sometimes you feel like it). Best done in the morning, when you’ll find these bugs sitting on top of the plants sunning themselves, but still a bit dopey in the cold. They stink (hence their other name – stinkbugs) and when the others smell this they’ll quickly scuttle away or drop off the plant, so you need to be a bit quick about it. No squeamishness allowed!