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Garden pests

Posted on Posted in Gardening tips

To prevent is better than to heal, so make your garden healthy and create an unpleasant environment for pests and disease, where your crops remain untouched.

Ground pest

Wireworms

Red-brown, firm worms are of different sizes, wind in fast movements on the surface and again disappear in the soil.

They are a threat to all vegetables, especially lettuce, root vegetables and tuber vegetables, as they eat their roots.

Protection and help:

  • Their natural foes are moles, birds, toads and Northern dune tiger beetles.
  • In spring, when soil temperature reaches at least 10 °C (50 °F), check the garden and prepare traps. Dig peeled apple slices or potatoes 10 cm (4 in) deep into soil. Remove them every second day and destroy together with the wireworms.
  • Keep the soil surface soft and moist.
  • Organic mulch prevents click beetles laying eggs in soil.
  • Plant Indian cress and tagetes alongside with potatoes and lettuce.
  • If wireworms are a common problem in your garden, do not plant clover, grains, lucern, gladioli, dahlias or asters.
  • Plant buckwheat, millet or flex in the problematic beds.
  • When wireworms appear in your garden, don’t sow crops directly into soil; use seedlings with root clods.
  • A natural help against wireworms is white mustard. Cut it just before blooming, dig into the soil under surface and water to start the process.
  • Use solutions with entomopathogenic nematodes or fungi – they are environmentally friendly and can be found in stores or online. Follow the instructions for use carefully and combine with the above mentioned traps.
  • In severe cases, use solutions with lime nitrogen, which emits a poisonous gas. Follow the instructions thoroughly.

Mole cricket

Mole cricket is a larger brown insect, similar to cricket, with shovel-like forelimbs.

It endangers all garden crops and attacks their roots and tubers.

Protection and help:

  • Its natural foes are birds, snakes and hedgehogs.
  • By tilling the soil, its tunnels get destroyed.
  • Stuff their tunnels with strong-odor material like herbs, lemons or fish oil.
  • Find its tunnels and nests, and pour boiling water in.
  • In October, dig a half a meter (1.5 ft) deep pit, 1 by 1 m (3 by 3 ft) wide, and fill with fresh barn manure. In February, burn or remove the whole pit content.
  • Use entomopathogenic nematodes or feverfew solutions.

Vole

A vole is an herbivorous rodent, similar to a rat, but with a shorter tail. Its tunnels are oval, while mole’s are round, and there are no roots in them.

A vole endangers all vegetable crops, as it eats their roots.

Protection and help:

  • Vole’s natural foes are birds of prey, grey herons, cats, snakes, weasels, skunks, foxes, badgers, hedgehogs.
  • Voles don’t like noise; put pinwheels on your garden or dig plastic bottles into vole’s tunnel –first cut the bottom of the bottle off and remove the cork, the put into the soil (turn them in different sides for the wind to cause different types of noise).
  • Plant crown imperials, garlic and Jimson weed to your garden, as voles don’t like their smell
  • Voles can’t stand the smell of elder as well; use flowers and leaves for mulch or soak them in water and pour the solution into vole’s tunnels.
  • Stuff the tunnels with leftovers of lemon, garlic, cypress or similar, to drive voles off your garden.

Nematodes or threadworms

Nematodes are small, transparent roundworms. Usually their eggs are easier to see than the live animals.

They endanger especially root vegetables, tuber vegetables and salad vegetables. The plants decay without any obvious reason and have deformed roots.

Protection and help:

  • A long enough rotation period.
  • Plant tagetes, calendula, Indian cress, Black-eyed Susan vine, common blanketflower.
  • Use oil radish, white mustard, Sudangrass or sorghum for green fertilization.
  • Destroy ambrosia and common knotgrass weeds, as they stimulate nematode’s reproduction.
  • Live, biological soil contains nematode’s natural foes – use organic fertilizers, compost, sawdust, carob flower or olive mill pomace.
  • Soil solarization: in summer, before planting sensitive crops, cover the soil with transparent polyethylene cover for three to four weeks.
  • Water the already attacked crops with a sugar solution or rhubarb liquid fertilizer.

Larvae

Larvae are fat, different colored maggots of beetles that can be found near the roots. They are hard to repel and can be doing harm up to three years.

They endanger all the vegetables crops, as they eat their roots.

Protection and help:

  • Larvae’s natural foes are moles, snakes and hedgehogs.
  • You can destroy them by digging the soil, as well as picking them out.
  • Use entomopathogenic nematodes.
  • Keep the soil soft.

Stem pests

Cabbage fly

This is a medium sized black fly with brown eyes, whose maggots cause harm to root crown.

It can harm especially the cruciferous plants, whose leaves get violet and the plant starts to decay.

Protection and help:

  • Natural foes are frogs and spiders.
  • A long enough rotation period.
  • Intercropping with herbs and flowers (chamomile, parsley, thyme, celery).
  • Put collars to the plants’ stems and make them fit closely (from cork, isolation material etc.).
  • Gather the soil around stems high.
  • When transplanting, sprinkle ash around the plants.
  • Cover with thick enough nets.
  • Use entomopathogenic nematodes.
  • During summer, spray the soil and the plants with solutions from yarrow, tomatoes, rhubarb, anis, fennel or carrots.
  • Use tomato plant for mulch.

Carrot fly

This is a grey-black fly with brighter head and legs. Its larvae cause harm in the garden.

They can attack carrots, parsley, parsnips, fennel and cumin. The leaves get violet and the plants start to decay.

Protection and help:

  • Natural foes are frogs and spiders.
  • Cover with thick enough nets (in June and August).
  • Plant in the vicinity: onions, garlic, leek, chives, lettuce, sage, coriander, mint, wormwood.
  • Protect the plants’ root crowns with soil, ash or mulch from the above listed beneficial plants (also elder).
  • Be careful not to harm the plants, as the pests get attracted by the smell.
  • Spread boiled leaves of black tea among young plants.
  • During summer, spray the soil and the plants two times a week with solutions from yarrow, rhubarb and feverfew.

Onion fly and leek moth

Onion fly is a small grey-brown fly. Its larvae cause harm in the garden in April, May and September by creating cavities in plants.

They are harmful to all bulb vegetables. The onions start to rot, young plants decay, and the mature crops are more difficult to store.

Protection and help:

  • Their natural foes are frogs and spiders.
  • Cover with thick nets (and make arches for support).
  • A long enough rotation period.
  • Be careful not to harm the plants, as the pests get attracted by the smell.
  • Use entomopathogenic nematodes.
  • Spray the soil and the plants twice a week with solutions from yarrow, rhubarb or feverfew.
  • Plant carrots, parsley, celery and parsnips in the vicinity.
  • Spread soil, ash or mulch around the leek’s neck.
  • Do not use barn manure at least for two years.
  • Spread ash around plants.

Light feathered rustic

Their larvae are grey-brown caterpillars and can be found in the evening, right under the surface, beside young plants.

They can harm all young vegetable crops. They also bite the stems of plants, right above the soil.

Protection and help:

  • Use entomopathogenic nematodes.
  • Dig the soil around the seedlings in the evening and pick the caterpillars.
  • Plant celery in the vicinity.
  • Spray the soil in the evening with fern, wormwood or feverfew tea.
  • Make mulch from tomato plant, fern, feverfew or elder.

Swede midge

This is a very small fly, similar to a mosquito, and is hard to notice. Its larvae harm the center leaves of plants.

It can harm all the brassica vegetables. It disables them to form flower heads – so the plants can stay without flower heads or form several smaller flower heads.

Protection and help:

  • A long enough rotation period.
  • Intercropping with herbs and flowers (chamomile, thyme, celery, parsley, lemon lime).
  • Make mulch from tomato plant.
  • Cover with thick nets.
  • Spray the soil and plants with fern, wormwood or feverfew tea.

Leaf pests

Lice

There are many sorts of lice and they cause different harm. They suck the plants and weaken them and deform their different parts.

They can cause harm to all vegetable plants.

Protection and help:

  • Their natural foes are ladybugs, hoverflies, lacewings, earwigs, birds, frogs.
  • Fertilize moderately.
  • In spring, remove the first colonies by hand, not to destroy the food for beneficial organisms (such as ladybugs) with spraying.
  • Make mulch from feverfew.
  • Use solutions from elder, nettle, feverfew, tomatoes, potato leaves, yarrow, rhubarb and Indian cress.
  • To strengthen the plants, spray them once a week with a mixture of milk and water (1:1).
  • Intercrop with garlic, onion, radish, cumin, thyme, sage, savory, tagetes.

Ants

Ants are not pests, but can cause problems if they spread too much.

Protection and help:

  • Make mulch from tomato plants, fern, lavender or mint.
  • Sprinkle coffee grounds between garden beds.
  • Set baits with sweet water.

Pea moth

Its caterpillar is a pest. The moth flies during the night in May and June.

It harms peas and beans. Their pods get full of holes and the pea moth caterpillar’s excrements.

Protection and help:

  • Make mulch from tomato plants.
  • Spray the soil and plants with solutions from elder, rhubarb or feverfew.
  • Sow peas earlier or later to avoid the pea moth.

Flea beetle

Flea beetle is a small, bright beetle that sucks on the leaves and is very difficult to get rid of the plants.

It harms brassica vegetables, horseradish, radish, beetroot and other cruciferous vegetables.

Protection and help:

  • Keep the soil moist (it does not like moisture).
  • Use mulch (from elder tree or tomato plant).
  • Plant lettuce and spinach in the vicinity.
  • During summer, spray the soil and the plants twice a week with solutions from wormwood, mint or feverfew.

Mites

Mites are not seen with our eyes, but their consequences are – numerous tiny dots on pale leaves of the plants they suck. The leaves eventually get yellow, brown or silver, while the leaf veins stay green in the beginning.

Mites harm especially beans, squash, eggplant and cucumbers.

Protection and help:

  • Their natural foes are ladybugs, spiders, hoverflies, lacewings.
  • Fertilize moderately.
  • Remove the attacked leaves in the beginning.
  • Use organic mulch.
  • Use home-made liquid fertilizers from horsetail, feverfew, rhubarb or wormwood, or garlic tea.

Thrips

Thrips are minute insect (2mm) of black or brown color, one of the most frequent garden pests.

They harm most of the vegetable plants, especially peppers, cucumbers, eggplant and bulb vegetables. They cause little elongated silver spots on the leaves of the plants they attack.

Protection and help:

  • Keep the soil moist and make mulch in early spring.
  • Do not keep anything blue near your garden.
  • Fertilize moderately.
  • Spray the endangered plants with garlic, onion or fern tea.
  • Keep your garden colorful with yellow, orange and red flowers.

Cabbage moth

Cabbage moth is a nocturnal butterfly of grey-brown color. The pest is its caterpillar. The eggs are grey and can be found on the lower side of the plant’s outer leaves.

It harms the brassica plants. Cabbage moth eats their leaves and causes big holes in them.

Protection and help:

  • Cabbage moth’s natural foes are birds, snakes, hedgehogs, mantises, ladybugs, lacewings, hoverflies.
  • Cover with thick nets.
  • Remove the eggs by hand.
  • Plant in the vicinity: chamomile, cumin, dill, calendula, Indian cress, spinach and celery.
  • Spray the soil and plants late in the evening with solutions from wormwood or feverfew.

Cabbage butterfly

This is a white butterfly (called also the large white), and its maggot is a green, and later yellow-black caterpillar. Its eggs are yellow and can be found on the lower part of the plant’s outer leaves.

It harms the brassica vegetables. It feeds on their leaves and makes big holes in them.

Protection and help:

  • Cabbage butterfly’s natural foes are birds, snakes, hedgehogs, mantises, lacewings and hoverflies.
  • Cover with thick nets.
  • Remove the eggs by hand.
  • Plant in the vicinity: chamomile, cumin, dill, calendula, Indian cress, spinach and celery.
  • Spray the soil and plants late in the evening with solutions from wormwood or feverfew.

Colorado potato beetle

This is a yellow-black beetle with stripes on its back. Its larvae are red.

It harms potatoes and eggplants.

Protection and help:

  • Its natural foes are birds, frogs, ladybugs and lacewings.
  • Make fern mulch.
  • Remove the eggs by hand.
  • Put open umbrellas or sheets under the plants and shake the plants; when the Colorado beetles fall off, destroy them.
  • Plant beans, garlic, catnip, coriander, Indian cress, horseradish, calendula in the vicinity.
  • Dust with rockdust.
  • You can use a leaf vacuum to remove the beetles of the adult potato plants.
  • Use solutions from feverfew, basil and mint.

Bean weevil

This is a small, oval beetle whose eggs are white. Its larvae have a bright body and a brown head.

It harms the bean family crops, especially beans. They lay their eggs in the bean pods. You can recognize their presence by characteristic round or oval holes on the surface of the bean grains.

Protection and help:

  • The threat of bean weevil attack comes only during summer when the July temperatures are very high.
  • When you pick the beans, remove the grains from the pod as soon as possible and freeze them for 3 days.
  • Store the bean grains in a clean and cool place in thick flex sacks.
  • Do not store the bean grains that have already been attacked and never mix them with the previous year’s yield.

Snails and slugs

You have to use various measures to protect your garden against snails and slugs:

  • Remove all the possible hiding places in the garden and its vicinity (bushes, higher plants).
  • Arrange your compost heap away from your garden beds.
  • There should not be any uncultivated areas around your garden – or you should plant the plants that drive away snails and slugs.
  • Pick the snails and slugs (best is early in the morning, when they have not hidden yet; you can also put a sliced potato for a bait; find them under wooden boards, in the hedge, in the compost and near the tagetes flowers, hostas and horseradish).
  • Make mulch from elder, yarrow, white cedar, horsetail, feverfew, and fern.
  • Sow white mustard around the garden beds (cut it before it blooms and use for mulch).
  • Snails and slugs don’t like the smell of onion, garlic, sage, thyme, Indian cress, Californian poppy, garden calendula.
  • Water the endangered garden beds with solutions from garlic, onion or snails brew.
  • Spread at least 10 cm (4 in) thick layer of sawdust, lime or rockdust around the garden beds and renew it after every rainfall.
  • Set purchased barriers, copper bands or old gutters around the garden beds.
  • Set snails and slugs traps: bury plastic containers into soil up to the edge and regularly pour beer inside – only fresh beer attracts them.
  • You can also use purchased solutions, but be careful they are not dangerous for other animals.
  • Their natural foes are hedgehogs, toads, slow worms and snakes.