Hi Tui, I have many hollyhocks in my flower gardens and they are infested with whitefly, how do I get rid of them? The leaves all shrivel and most dry off.

Hi Marrion, whitefly are prevalent in hot dry weather, and difficult to control, the secret is to break the lifecycle of the insects. There are insecticides that control whitefly such as pyrethrum based sprays, talk to your local garden centre for a suitable control. Whitefly do seem to build up an immunity to insecticides. Insect pests usually appear on plants when plants are under stress. By keeping your plants well watered, regularly fed and the soil mulched through summer will help keep plants actively growing and more resistant to pest and disease attack. Regular feeding with a seaweed based plant tonic such as Tui Organic Seaweed Plant tonic also helps protect plants by strengthening the cell wall of the plant, this makes the leaf surface harder for sucking insects to pierce. Remove all plant material at the end of the season and burn or dispose of in the rubbish, do not compost, as insect eggs can overwinter in rotting plant material. Make sure your garden is weed-free as these are a host to insect pests and they can overwinter on weeds as well. The Tui Team.