Yesterday my much anticipated delivery from Defenders arrived at the towers full of bugs to help me keep the greenhouse free of whitefly and red spider mite. Last year the creepy crawlies certainly seemed to be very effective and I ordered the same again. Phytoselius chomp on their near relatives, Red Spider Mite, and Encarsia formosa chow down on whitefly larvae.
There is often confusion about whitefly; unlike greenfly and blackfly, whitefly are not aphids. Aphids have squishy bodies and even the winged ones don’t take to the air an awful lot whereas whitefly take off at the merest excuse and tend to hold their wings rather like miniature white moths when they are at rest. If you go near your tomatoes and are engulfed in a cloud of little white insects, they’re whitefly. In some years our tomatoes have been covered in thick coats of sooty mould thanks to the whitefly. Sooty mould is a secondary problem coming along with any sap-sucking insects (such as whitefly or aphids). Their excreta, called honeydew, is sticky and sweet and tends to go black and mouldy. This can damage the plant by preventing photosynthesis and is pretty nasty when it’s all over your tomatoes!
This year I’m looking forward to tomatoes and cucumbers free from insectoid munchings and excretions.