Gardeners Tips

Small Cabbage White Caterpillar (pic)

Large Cabbage White Caterpillar are yellow with black markings

Caterpillar Problems

• There are a large variety of caterpillar from different species of moths, butterflies and saw flies.
• Brassicas are particularly susceptible to three common types the large cabbage white butterfly, the small cabbage white butterfly and the cabbage moth respectively Pieris brassicae, Peiris rapae and Mamestra brassicae.
• Butterflies lay their eggs on the outer leaves of the brassica which hatch in 4 days to become voracious feeding larvae.
• In addition to eating irregular shaped holes in leaves they often burrow into the hearts of cabbages.
• Damage to plants will occur in April and October as the butterfly produces two generations per year.

Caterpillar Control

• Avoid the butterflies by netting the brassicas.
• Pick off any caterpillars by hand.
• Squash any eggs that are found under the leaves before they develop.
• Try a biological control from a parasitic wasp that lays its eggs in the caterpillars eg Cotesia glomerata
  
• Grazers natural formula is sprayed directly on to the foilage which helps protect the plant from damage.
• Spray with the contact pyrethroid insecticides but remember you plan to eat the brassica.
• Distract the butterflies by planting nasturtiums as an alternative breeding ground.

Grubs of the daddy long legs or species of Tipula attract birds to peck at your lawn. More importantly nthe feast on the roots of your turf.

Grub Problems on Lawns

• Leatherjackets  are larvae or grubs of the  Crane Fly or Daddy Long Legs as they are more commonly known.
• Leatherjackets live for one year from eggs laid in September, eating there way through winter
• The fully grown Larvae are grey brown maggots up to 4 cm in length and have grown that size by eating the roots of your grass.
• Leatherjacket problems can be recognised when your lawn starts thinning and going bare.
• During dry spells in summer the grass may go yellow-brown caused by the grubby eating habits.
• The less common larvae of Chafer Beetles  live for 3 years in the soil but the effect can be the same as Daddy Long Legs grubs. They are creamy white, C-shaped with brown heads and look similar to vine weevil.

Prevention And Control

• Chemical insecticides have been banned by EEC for garden use against these grubs.
• On a wet day cover the lawn overnight with some black plastic . When you remove it the next morning the grubs will be on the surface to feed the birds.
• Nematode products utilise natural predators such as nematodes, lady-bird and lace-wing larvae that break the life-cycle of the pest. These solutions boost the number of natural predators and have no detrimental effect upon the lawn.

Nematodes from Amazon

Earwig O

Earwigs look worse than the bites they take out of plants. Some years there may be large infestations.

Earwig Problems

• Whilst Clematis, Dahlia and Chrysanthemum plants may be a bit chewed  and ragged by an earwig they will not come to great harm unless you are growing show blooms.
• Larger infestations  can strip the soft green parts to a network of veins.
• Earwigs eat large irregular holes in the leaves and petals can be damaged by droppings.
• Earwigs feed their newly hatched young on aphids and other small insects.
• During the day earwigs hide amongst the petals. The leaves of Dahlias can be ravaged by
• Earwigs do not bite or spread disease.

Earwig Control

• To catch these night feeders use a torch.
• The inverted plant pot on a cane method with the pot filled with straw or well crumpled newspaper will act as a trap. You can then collect the earwigs for destruction.
• Birds, frogs and toads that prey on earwigs will help reduce the population of earwigs and keep it under control.
• Chemical controls such as permethrin should be applied at dusk on warm evenings. Treat the leaves blooms and the  soil below the plants.
• Prevention by removing moisture and decaying vegetation will make conditions less hospitable for earwigs.

Woodlice

Woodlice are generally seen as scavengers who eat rotting matter, they are not thought of as harmful to the garden. However, they do chew leaves and stems of tomatoes and cucumber in the greenhouse. They are not true insects but a species of crustacean.

Seedlings can be  eaten by woodlice before the seedlings become established. They can eat stems and leaves so woodlice are best destroyed.

Control and Problems

• Woodlice and millipedes can be controlled using ant and insects powders historically Methiocarb with HCH lindane
• Keep areas clear of any debris
• Recycle woodlice you capture on to the compost heap.
• Squishing and squashing woodlice is a common cure.
• Woodlice like damp dark places with a source of rotting wood to lay their eggs.
• Woodlice are unsightly particularly if they invaded the home where they like damp and rotting wood.

Notes

Methiocarb  is a molluscicide and insecticide for control of slugs, snails and many other pests. In 2014 the EU banned Methiocarb poison-baited pellets  due to their hazardous effect on grain-eating farm birds

Nippon Woodlice Killer based on permethrin