How can you control spider mites on tomatoes? - briefly
Apply miticides (e.g., abamectin, neem oil) or release predatory mites such as Phytoseiulus persimilis, and prune heavily infested leaves. Keep humidity low, water at the base, and inspect plants frequently to catch new infestations early.
How can you control spider mites on tomatoes? - in detail
Spider mites thrive in hot, dry conditions and can rapidly defoliate tomato plants. Early detection relies on inspecting the undersides of leaves for tiny moving specks or fine webbing. A magnifying lens helps confirm the presence of mites, which appear as six‑legged, oval organisms measuring 0.2–0.5 mm.
Cultural practices
- Maintain humidity above 60 % by misting foliage or using drip irrigation instead of overhead watering.
- Space plants 18–24 inches apart to improve airflow and reduce leaf temperature.
- Remove heavily infested leaves and dispose of them away from the garden.
- Rotate crops annually; avoid planting tomatoes in the same bed for more than two consecutive years.
Biological agents
- Release predatory mites (e.g., Phytoseiulus persimilis, Neoseiulus californicus) at a rate of 10–20 predators per square foot.
- Apply entomopathogenic fungi such as Beauveria bassiana according to label directions; repeat applications every 7–10 days during outbreaks.
- Preserve natural predator habitats by planting flowering herbs (e.g., dill, fennel) nearby.
Organic sprays
- Mix neem oil at 1 % concentration and spray the entire plant, covering the leaf undersides; repeat every 5–7 days.
- Use insecticidal soap (2–5 % fatty acid solution) for immediate knock‑down; avoid application in extreme heat to prevent phytotoxicity.
- Apply horticultural oil (e.g., mineral oil) at 1 % before sunrise or after sunset; reapply after heavy rain.
Synthetic acaricides
- Select products labeled for tomato use, such as abamectin or bifenthrin, and follow the maximum recommended rate.
- Rotate chemicals with different modes of action to delay resistance development; adhere to a 7‑day pre‑harvest interval.
- Observe local regulations regarding residue limits and re‑entry intervals.
Integrated management
- Monitor weekly; record mite counts per leaf.
- Implement cultural controls as a baseline.
- Introduce predators when populations exceed 5 mites per leaf.
- Apply organic sprays if predators are insufficient.
- Reserve synthetic acaricides for severe infestations, using them sparingly.
Consistent scouting, environmental modification, and the strategic use of biological and chemical tools together provide effective, long‑term suppression of spider mites on tomato crops.