Maggots are fly larvae that can be found on rotting vegetation and around the roots of garden plants such as corn, onions, turnips, carrots, cabbage, and even fruit trees. They can cause a lot of damage to the plants by eating their root systems, destroying their method of obtaining water or nutrients from the soil.
Usually, if you've spotted maggots, your garden plants are already damaged. While there are many ways to get rid of these garden pests when you see them, the best way to fully protect your garden is to take preventative measures once a year. Follow these steps to get rid of any maggots you currently have and reduce the chance of getting more maggots.
Step 1 - Find the Maggot Infestation
If your otherwise healthy plants are suddenly wilting or if their growth has been stunted, there's a good chance you have a maggot infestation. The best way to find out if you have this problem is to carefully pull a few of the plants from the soil and examine the roots. If you see just one squirming grayish- or yellowish-white worm, then you know you have a maggot problem. Use your gloved hand to shake the soil to see if there are any more.
If they're small, then you know they've just recently hatched and probably haven't done much damage. Large maggots are older and have likely had a chance to do more damage to your plants by eating more of their root systems.
Step 2 - Stop the Spread
There's not a lot you can do to save an infested plant. If your lucky enough to have caught the problem early, there are a few things you can do to stop any other plants from becoming infected.
First you need to remove the dying plants and the soil around the dying plants. The rot from dying plants will attract the root maggot fly which increases the chance of it laying more eggs and starting the cycle all over again. The soil around the destroyed plants also needs to be removed in case it is infested with eggs.
Infested plants and soil should be burned or thrown out in a double sealed plastic garbage bag. Do not compost them.
Step 3 - Kill Any Missed Maggots and Eggs
Even after completing the above step, there's a chance you could have missed a single maggot or fly egg pod which will start the maggot cycle all over again if not treated.
Dust your plants with diatomaceous earth. It's a fine powder made out of the fossilized remains of a type of hard-shelled algae. It dries out maggots and other garden pests causing them to die.
Apply beneficial nematodes to your garden when it's damp. Nematodes are living organisms that will eat maggots. Simply add them to water and spray over the surface of your garden when the temperature is at least 55 degrees Fahrenheit. Water the nematodes for two days after application.
Step 4 - Prevent Future Infestations
Prevent maggot flies from laying their eggs near your plants by covering them with floating row covers. The flies prefer to lay their eggs in cool, moist conditions. Try solarizing your plant beds to make them drier and warmer.
Keep your compost away from your garden since rotting vegetation will attract flies. Also keep garbage away from your garden and regularly clean out garbage cans.