Basil Plant and Mites

Spider Mites

• Spider mites are the most common mite affecting basil plants. Spider mites are tiny arachnids that spin their webs over their host plant. Six varieties of these mites exist; four of them are considered warm weather pests and two are considered cold weather varieties. The warm-weather mites live on basil. Spider mites live mostly on the underside of the basil's leaves and lay their eggs near the leaves' veins. They can develop from eggs into adults within a week during warm weather, so infestations occur rapidly.

Signs of Infestation

• Immediate signs of mite infestation are webbing across the leaves and stems and tiny specks on the foliage. This is followed by a bronze coloring and leaf scorch. If the infestation is not controlled, it can quickly lead to significant damage; injury can lead to leaf loss and even plant death.

Treatment

• Treating spider mite infestations is often difficult. Not only do insecticides kill the insects that prey on them, but they can also contaminate the basil. A few non-chemical ways are worth trying to eliminate a spider mite infestation on your basil plant. When watering, direct a strong stream of spray onto the plant, especially on the underside of the leaves. This can knock the mites off and disrupt their webbing. Make a mixture of dish soap and water, and spray it over the entire plant; this will often disrupt the colony, knocking the mites off, or suffocating them and preventing them from reproducing. If you have to resort to miticides, ensure to wash the basil leaves thoroughly before using them.

Prevention

• One way to prevent spider mites is to encourage their natural predators. These include lady beetles, predatory thrips, pirate bugs, and some predatory mites, such as Phytoseiulus spp., Amblyseius spp. or Metaseiulus spp. Spider mites infestations can do serious damage to basil plants suffering from drought conditions, so keep basil plants well-watered, especially in dry or hot weather. While watering, aim a few good shots of the hose or the sprayer onto the underside of the basil leaves; this prevents the mites from establishing themselves and spinning webs. Always inspect new plants for signs of infestation before planting them next to your basil, and quarantine them until you ascertain there are no spider mites on them.