Neem Oil Spray Calculator & Neem Oil, Soap & Water
Mixes for aphids
Mix an organic neem oil spray right — from your spray volume and strength get the neem oil, the emulsifier (soap) and the water, with per-tank amounts.
Enter your spray
Next: test the mix on a few leaves first and wait a day — concentrated neem can scorch tender foliage in hot sun.
Neem oil 0.5–2% v/v; add emulsifier or it won't mix; use within hours.
Neem oil spray — key facts
- Strength
- 0.5–2% (5–20 ml/L)
- 1% spray
- 10 ml oil + ~1 ml soap / L
- Emulsifier
- needed or oil won't mix
- Spray when
- cool morning/evening
- Coverage
- both leaf surfaces
- Repeat
- every 7 days, 2–3 times
- Use
- fresh, same session
- Privacy
- Runs in your browser; nothing uploaded
The organic spray, mixed to the right strength
Neem oil is the workhorse of organic pest control — it deters, disrupts and starves soft-bodied and chewing pests without the residues of synthetic insecticides. But it only works if it's mixed right: oil won't blend with water on its own, so it needs an emulsifier, and the strength has to suit the plant or it can scorch. Guesswork leads to separated, ineffective or leaf-burning sprays.
This tool gives the exact neem oil, soap and water for your spray volume and chosen strength (0.5–2%), plus per-tank amounts so each load is accurate. Emulsify the oil properly, spray fresh in the cool of the day covering both leaf surfaces, and repeat weekly to catch newly hatched pests. Test on a few leaves first. Pair it with the Bordeaux Mixture, Spray & Tank Mix and Economic Threshold tools.
Mix it right
Exact neem oil and soap so the spray emulsifies and works.
Avoid leaf burn
Right strength for the plant, sprayed in the cool.
Per-tank amounts
Know what to add to each knapsack or tank.
Go organic
Control pests without synthetic-pesticide residues.
Frequently Asked Questions
How much neem oil per litre of water?+
Usually 0.5–2% by volume — that is 5–20 ml of neem oil per litre of water, plus an emulsifier so it mixes. A common 1% spray is 10 ml neem oil + about 1 ml mild soap per litre. This tool gives the exact neem oil, soap and water for your spray volume and strength.
Why do I need soap with neem oil?+
Oil and water don't mix, so neem oil floats and won't coat the plant evenly. A mild emulsifier — a little liquid soap or dish-wash — breaks the oil into fine droplets that stay suspended. Without it, the spray separates and you get patchy, ineffective coverage and possible leaf burn from oil blobs.
What strength of neem oil spray should I use?+
0.5% for tender seedlings and sensitive plants, 1% for general pest control, up to 2% for heavier infestations on hardy plants. Higher isn't always better — strong oil sprays can scorch leaves in heat. Start at 1% and adjust. This tool supports any strength you enter.
What pests does neem oil control?+
It works on soft-bodied and chewing pests — aphids, whitefly, mealybugs, thrips, mites, jassids, scale and young caterpillars — and suppresses some fungal diseases like powdery mildew. It acts as a repellent, antifeedant and growth disruptor rather than a quick knock-down, so it works best applied early and repeated.
How do I mix neem oil spray correctly?+
Warm the water slightly, add the emulsifier and stir, then add the neem oil slowly while stirring to form a milky emulsion, and finally top up with the rest of the water. Use it immediately. The tool gives the amounts; always mix only what you'll spray that session.
When should I spray neem oil?+
In the cool of early morning or evening, never in hot midday sun (oil + heat scorches leaves and the spray degrades faster). Cover both leaf surfaces, especially the undersides where pests hide. Repeat every 7 days for 2–3 sprays to catch newly hatched pests, as neem isn't a one-shot kill.
Can neem oil damage my plants?+
Yes if misused — too strong a mix, spraying in hot sun, or on very tender new growth can cause leaf burn. Always emulsify properly (oil blobs scorch), use the right strength for the plant, spray when cool, and test on a few leaves first before treating the whole crop.
Is neem oil safe and organic?+
Neem oil is plant-derived and approved for organic use; it's relatively gentle on beneficial insects when dry and breaks down quickly. Still, spray in the evening to avoid bees, avoid spraying open flowers, and keep it off water bodies. Wear basic protection and observe any label pre-harvest interval.
How much spray do I need for my area?+
Spray volume depends on crop size and density — often 200–500 L/ha for field crops, less for young plants. Enter the total volume directly, or switch to 'by area' and give your spray volume per hectare and the area; the tool then sizes the neem oil and soap for the whole job.
Can I store leftover neem spray?+
No — mixed neem oil spray breaks down within hours, the emulsion separates, and it loses effectiveness. Always prepare fresh and use it the same session. The tool's per-tank amounts help you mix just what each tank needs so nothing is wasted.