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PESTS, DISEASES AND OTHER PROBLEMS – AN ORGANIC APPROACH

Cabbage white caterpillars

Polytunnel growing can be a mixed blessing when it comes to pests and diseases. It’s easier to keep polytunnel crops isolated from all that threatens plants growing outdoors, but once something finds its way into a warm, humid, confined space, the rate of spread can be rapid indeed. The key to healthy crops is a healthy growing environment.

Mealy aphids

A few rules for healthy crops

•  Keep your eyes open for any potential problem before it gets out of control.

•  Keep the soil in good heart.

•  Use organic techniques to regain some balance in the situation.

•  Remove any foliage that is damaged by disease.

•  Remove any affected plants if necessary.

•  Make sure plants get enough water, but not too much.

•  Make sure enough air can circulate around growing crops.

•  Try to keep temperatures below 30˚C/86˚F.

It’s possible that there will be no real problems in the first year of polytunnel growing, but these will build up over subsequent years. Every gardener has to cope with some pests and diseases at some point. Every gardener loses the odd plant, or has something that doesn’t crop well. Don’t panic! Lots of plants grow perfectly well while tolerating some level of disease or colony of pests. And a problem that raises its head one year may disappear for the next. Don’t automatically reach for something poisonous to kill pests and diseases out of hand. Growing great crops is all about balance. If a spray kills a predator as well as a pest, a different pest, which the predator previously kept under control, might start to build up numbers instead.

Most problems have a solution and most solutions can be organic. Environmentally friendly options don’t have to be less effective than any other kind. Work with the best that nature can offer and the rewards will be the best that nature can supply.