November 30, 2010
Every spring, you get your organic crop of tomatoes kicking along, you feed, you mulch, you train, you pamper, the fruit look plump and fantastic, until you cut them open and find it’s been destroyed by a fat ugly caterpillar. It’s more than heartbreaking – it’s simply devastating for any gardener.
It’s best known as a tomato caterpillar or budworm (Helicoverpa spp) and it’s a very common spring pest, especially where I garden in the sub-tropics. The good news is, it can be controlled using organic products, but you need to understand a bit about the lifecycle and habits of the pest.
The eggs of the caterpillar are laid by a moth, usually on the leaves. Once they hatch, they feed briefly on the leaves as they work their way to the flowers, and then into the fruit at a very early stage of its development. We don’t notice the damage in the garden until it’s far too late.
You can spray with eco friendly Dipel or spinosad to control this caterpillar, but you need to spray the leaves and flowers as soon as flower buds appear. New flowers are coming on all the time, so to make the strategy effective, you should spray at least once a week, and reapply after rain.
For more tips on how to grow tomatoes with environmentally friendly controls for pests and diseases, be sure to check out Peter Cundall’s tomato story in the Jan/Feb 2011 Issue of Organic Gardener magazine.