Bacillus thuringensis Bt

This is a bacterium that parasitises the caterpillar and causes fatal vomiting. Trade names are Dipel and Thuricide.

Use of aromatic herbs:

Attractants to lure pests away from crops - plant hyssop near cabbage (an excellent lurer, entices away cabbage white butterfly and stops infestations of caterpillar, especially the cabbage white butterfly), also coriander and wormwood.

Organic sprays:

Garlic:

1. Soak 75g chopped garlic bulbs in 2tsp mineral oil for 24 hours. Add 1 pint water mixed with 7g soft soap. Stir well and strain in non-metallic container and store. To use: dilute 1 part of mixture to 20 parts water.

2. Boil 10 cloves garlic, 4-5 very hot chillies, 2-3 onions for 5-10 mins. Stand overnight. Add liquid soap or milk. Store in glass bottle. To use: 1 small cup mixture to 7 litres water.

Pyrethrum:

Grind dry flowers or extract with kerosene. Remains toxic for 12 hours. Non toxic to mammals, but this will kill bees, ladybirds and other beneficial predators. Spray in evening when bees etc, are less active.

Salt spray:

50g common salt to 3.7 litres water.

Soap spray:

Use soft soap (made with potassium carbonate and not caustic soda) Dissolve 50g in 4.5 litres hot water. Apply when cool.

Bordeaux mixture (copper sulphate spray):

100g copper sulphate dissolved in 1 litre of hot water. Add mixture to 150g hydrated lime in 1 litre water. Stir well. To use: Dilute with 10 litres water. For spring use, dilute further 1 part mixture to 10 parts water. Use within 24 hours of making up. Use at 2-3 weekly intervals.

Encourage beneficial insects:

Coccinella Leonina

Coccinella Undecimpunctata

German wasp (vespula germanica). Common wasp.

Hoverflies, syrphid - encourage with pollen and nectar flowers, especially blue, yellow or white colours; also use phacelia, daisies, yarrow, white cosmos and French marigold.