How frequently should neem oil be applied?
Written by
Tina Carter
Reviewed by
Prof. Martin Thorne, Ph.D.Consistent application frequency of neem oil establishes whether you will win the battle against spider mites. Apply it every 5-7 days for a total of three weeks to break their lifecycle. This timeframe is targeting the newborn nymphs before they can lay eggs. If you miss a single treatment, any surviving spider mites may start the lifecycle over again. Repeat and consistent applications will break the reproductive cycle of the spider mite.
Mixing & Timing
- Dilution: 2 tbsp neem oil + 1 tsp soap per gallon
- Spray time: Dawn/dusk to avoid leaf burn
- Temperature: Below 90°F (32°C) only
Lifecycle Targeting
- Days 1-7: Kill active adults and nymphs
- Days 8-14: Eliminate newly hatched larvae
- Days 15-21: Prevent egg-laying survivors
Safety Protocols
- Test plants: Apply to 2-3 leaves first
- Bees: Spray after pollinators leave at dusk
- Rain: Reapply after heavy downpours
You can mix neem with insecticide soaps to deal with more stubborn infestations. The soap breaks down mite coatings and allows neem's azadirachtin to penetrate the pest faster. I have successfully revived a basil crop this way after not having success for several weeks with neem applied by itself. For heavy outbreaks, I recommend applying the neem - insecticidal soap mix at 7-day intervals.
Do not apply the neem oil during the middle of the day. Neem oil's active ingredients degrade from UV exposure and high heat can cause phytotoxicity. My client applied neem oil after 11 AM on their tomato leaves and they developed brown spots. The best time to apply neem oil is in the early morning when temperatures are below 80°F (27°C) to allow optimum absorption into the plant.
Keep neem oil in dark and cool areas. Both heat and light will decrease their effectiveness in just a few weeks. Purchase small bottles of neem oil so that you use it before it loses its potency. Do not hesitate to throw away any old solution containing neem oil, as it is ineffective after 8 hours. Using a freshly mixed solution guarantees you are getting the maximum mite knockdown power at each application.
Read the full article: Spider Mite Control: Proven Strategies for Healthy Plants
