Neem Oil Spray Calculator & Neem Oil, Soap & 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.

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.

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.

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.

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.

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.

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.

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.

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.

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.