Plant Doctor Archive

 MY friend is plagued with a whitefly in his cucumbers and tomatoes. What should he do?

 WHITEFLY multiply quickly and so can be difficult to control. Spray with a pyrethrum based spray such as Target. There is a three-day withholding period after using this spray, so do not harvest fruit within three days of spraying. Reapply the spray at five to 10 day intervals if the infestation is heavy, after that, spray as required.

If the tomatoes and cucumbers are growing in a glasshouse, a Trappit insect trap can be used. This is a sticky yellow board containing a pheromone that traps the male whitefly. These are available from hardware stores and garden centres.

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