Garlic is a flavorful and nutritious herb that is grown in many gardens around the world. However, it is not uncommon for garlic plants to be attacked by various pests, which can harm or even kill the plants if not properly controlled. In this article, we will discuss some common garlic pests and effective ways to deal with them in the garden.
Pests and Diseases
Garlic Root Maggot
Garlic root maggots are small, yellowish-white maggots that feed on the roots of garlic plants. They can cause stunted growth, yellowing leaves, and even death of the plant. These pests are commonly found in regions with cool and wet climates.
To deal with garlic root maggots, it is important to prevent infestation in the first place. Start by planting garlic in well-drained soil that is rich in organic matter. Garlic plants should also be spaced far apart to reduce the chances of overcrowding, which can attract pests.
You can also cover the plants with a floating row cover to protect them from maggots. This can be especially effective during the early stages of growth when the maggots are most active. If you notice signs of infestation, such as yellowing leaves or stunted growth, you may need to use an insecticide to control the pests. Make sure to follow the instructions on the label carefully and apply the insecticide in the evening, when the maggots are most active.
Aphids
Aphids are small, pear-shaped insects that feed on the sap of garlic plants. They can cause distorted leaves, stunted growth, and can transmit viruses to the plants. Aphids can be green, black, or brown, and can often be found in large groups on the leaves and stems of garlic plants.
To deal with aphids, start by inspecting your garlic plants regularly for signs of infestation. If you notice large groups of aphids, you can use a strong spray of water to knock them off the plants. You can also apply insecticidal soap or neem oil to the plants to kill the pests.
Another effective method is to introduce natural predators of aphids, such as ladybugs or lacewings, into your garden. These predators can help to control the population of aphids without the need for chemical pesticides.
Thrips
Thrips are small, slender insects that feed on the leaves and stems of garlic plants. They can cause distorted leaves, stunted growth, and can transmit viruses to the plants. Thrips are typically brown or black and can be difficult to see with the naked eye.
To deal with thrips, start by inspecting your garlic plants regularly for signs of infestation. If you notice distorted leaves or stunted growth, you may need to use an insecticide to control the pests. Make sure to follow the instructions on the label carefully and apply the insecticide in the evening, when the thrips are most active.
You can also introduce natural predators of thrips, such as predatory mites, into your garden. These predators can help to control the population of thrips without the need for chemical pesticides.
White Rot
White rot is a fungal disease that affects garlic plants. It can cause the bulbs to rot and become soft, which can lead to reduced yields and poor quality garlic. White rot can be especially common in regions with humid climates.
To prevent white rot, it is important to plant garlic in well-drained soil that is free from standing water. Garlic plants should also be spaced far apart to reduce the chances of overcrowding, which can promote the growth of fungi. You should also avoid planting garlic in the same location every year, as this can lead to a buildup of fungal spores in the soil.
If you notice signs of white rot, such as soft bulbs or a foul odor, you should remove the infected plants immediately and dispose of them in a way that prevents the spread of spores. This can include burying the plants in a deep hole or burning them. You should also avoid planting garlic or other alliums in the same location for at least 3 years to prevent the spread of the fungus.
To prevent the spread of white rot, you can also apply fungicides to your garlic plants. Make sure to choose a fungicide that is labeled for use on garlic and follow the instructions on the label carefully. You should also apply the fungicide before the onset of symptoms to prevent the spread of the fungus.
Nematodes
Nematodes are small, microscopic worms that can feed on the roots of garlic plants. They can cause stunted growth, yellowing leaves, and even death of the plant. Nematodes are commonly found in regions with warm and humid climates.
To deal with nematodes, it is important to prevent infestation in the first place. Start by planting garlic in well-drained soil that is rich in organic matter. You should also rotate your crops regularly to prevent the buildup of nematodes in the soil.
If you notice signs of nematode infestation, such as yellowing leaves or stunted growth, you may need to use an insecticide to control the pests. Make sure to choose an insecticide that is labeled for use on nematodes and follow the instructions on the label carefully.
Cutworms
Cutworms are small, brown or gray caterpillars that can feed on the stems of garlic plants. They can cause wilting, yellowing leaves, and can even cut the stems of young plants at the soil level. Cutworms are commonly found in regions with cool and wet climates.
To deal with cutworms, it is important to prevent infestation in the first place. You can start by applying a layer of diatomaceous earth around the base of your garlic plants. This will create a barrier that cutworms cannot cross. You can also use collars made from cardboard or plastic around the stems of young plants to prevent cutworms from reaching them.
If you notice signs of cutworm infestation, such as wilting or yellowing leaves, you may need to use an insecticide to control the pests. Make sure to choose an insecticide that is labeled for use on cutworms and follow the instructions on the label carefully.
Best Practice
This sounds too simple to be true, but the best practice is to pay attention to your garlic. If you see or smell something weird, than something is likely needing attention.
Many of the pests mentioned in this article are above ground and can be managed if they are noticed. Unfortunately underground pests are less immediately noticeable but will show themselves in pre-maturely browning, excessively small, or wilting plants.
If you have a problem in any given year, especially with white rot, it’s best that you move your garlic into other areas. Many farmers swear by crop rotation for this very reason. If your plant isn’t planted in the same area it’s possible (likely) the pests will be confused.
Garlic pests can be a frustrating problem for gardeners, but with the right knowledge and tools, they can be effectively controlled. Keep your hopes up and your eyes open.