Hi, I live in Taranaki, and have just picked and uprooted my broccoli plants which were growing in a hothouse, they had loads of white bugs under the leaves. Will these affect other things in the hothouse even though the infected plants are now removed. Please help as I am new to vegetarian gardening, many thanx.

Hi Kathryn, these are whitefly and are a common garden and glasshouse insect pest. They are a sucking insect and are not super fussy as to which plants they feed on. They can overwinter in your glasshouse and live on host plants such as weeds (especially milkweed) over winter, so keeping your hot house weed free is the best way to keep them at bay. Keep your plants well watered, regularly fertilised and give them the best growing conditions you can, so that your plants don't get stressed due to lack of water or fertiliser, is the best way to keep them pest and disease free. Regular applications of Tui Certified Organic Seaweed Plant Tonic throughout the growing season will also help by strengthening the cell wall of the plant to make it harder for pests to invade. You can get sticky yellow phermone traps which are a natural way of controlling whitefly from your local garden centre or hardware store to hang in the hot house, this helps break the life cycle and can be hung even when there are no plants in the hot house. Lianne, Tui Team.