Wireworms are the slender, yellowish-brown, hard-bodied larvae of several species of click beetles. There are many species of wireworm , various species attack Beans, Carrots, Beets, Celery, Lettuce, Onion, Sweet potato, turnip, and mustard . These worms reek their havoc by puncturing and tunneling stems, roots and tubers. Carrots are a particular favorite. - Insect Pests of Carrots
Wireworm larvae as well as adults will overwinter in the soil. In early spring they emerge mate and lay eggs just under the surface, which can make detection difficult. They take up to a month to hatch , but can hatch in as little as two weeks.
Once hatched they commence traveling through the soil in search of food. The Larvae will feed underground for up to 6 years with most of their damage occurring in early spring while soil temperatures are still cool. Pupation occurs later in summer and adult beetles emerge in the spring and begin the circle of life anew. There is one new generation annually, the life-cycle, as stated requiring up to 6 years to complete.
They also feed on the seeds prior to germination or shortly after germination. If the plants do germinate at all they will continue to deteriorate, because wireworms bore into underground portions of the stem causing further wilting and ultimately death.
They continue to feed upon the small roots of many plants throughout the season. Wireworm larvae are generally hard, burnt brown, smooth, varying from 1/2 to 1-1/2 inches in length when full grown. Some species are soft, and white or yellowish in color.
False wireworms and wireworms, although differing varieties, have basically the same effect and treatment
Diagnosis - Wireworms
Clear the garden bed of weeds. mulch and plant debris. Lay down a wooden board or boards in your garden bed - plywood or whatever you have space for, and leave it there overnight. Check under the boards in the next morning and you should find wireworms as well as other pests attached.
Take the board ,bugs and worms to an area away from your garden where you can either have a bug massacre with insecticide or release them where they can't do any harm to your plants.
Thorough cultivation deprives wireworms of the conditions needed for egg laying and exposes all stages of this pest to the elements as well as natural enemies.
Add compost to where the wireworms infestation occurred. Add organic fertilizer that contains green manure, which also will help to kill any wireworms you may have missed. Continue managing your garden by cultivation, removing weeds and applying organic fertilizer regularly. Don't spray pesticide on the area to remove or prevent the wireworms from returning as it could easily do more damage than the wireworms ever could.
Garlic is another way to get rid of wireworms as well as ants, aphids, caterpillars, Colorado beetle, diamondback moth, whitefly, cabbage worm, mice, mites, moles, termites and vampires, as well as some fungi and bacteria.
Garlic is a broad spectrum natural insecticide. This means that it will kill beneficial insects as well as pests. Try to spray only the affected areas where pests are doing the most damage.
Potato Trap for wireworms
Potatoes make excellent wireworm traps. Slice a potato in half and run a stick through the center. Bury the spud about an inch deep leaving the stick stands protruding upwards as a handle. Pull the stick out every few days and dispose of any wireworms attached.
Beneficial nematodes in the soil will attack and destroy insect pests.
Pyrethrin drenches, in severe infestations are also recommended, but only as a last resort.
Use Broad-spectrum insecticides, such as pyrethin only as a last resort. Sprays/Pesticides must be applied in the pre-bloom stage to prevent injury. Pesticides such as pyrethroids that are more effective in cool than warm weather will work more efficiently against worms earlier in the season, and is the recommended early season chemical treatment for most worms.
Proper sanitary practices are vital to the health of your garden. Proper sanitation can help to ensure disease-free pest-free and productive gardens. Try to keep the garden free of any diseased dead or damaged plant materials. Remove cuttings from pruning and trimming and either destroy them - if diseased, or send them to the compost pile. Leaving rotting fruits and vegetables in the garden is like a written invitation to unwanted pests and diseases.
If a diseased or dead plant part has to be cut, the microorganism that caused the problem is probably on the tool you just used. Like a surgeon, sterilize all tools by washing in soap and water - rubbing alcohol wouldn't hurt either. If you pinch off diseased plant parts, wash hands before handling any other plants. Keep Weeds under control. Till the soil in the spring before planting to expose and kill larvae that wintered over in the soil.