Various extracts from the Neem tree have been used for pest control for centuries, but there has been little science available. Early neem products were rough, instructions based on guesswork, and results variable. In recent years science has caught up, with new formulations free of natural toxins, and providing more reliable results. Three neem products are now registered and approved for use on edibles—
The active ingredient in Neem, azadirachtin, is of low toxicity. It does not kill insects on contact as a poison would. It is an antifeedant, which stops insects feeding and they starve to death. A secondary mode of action is disrupting development of insects, so they never become adults, reducing the population.
Neem is most effective against small sucking insects (aphids, white fly, thrips, mealy bug, scale and mites) or very early stages of others, (caterpillars, shield bug, passion vine hopper)
Best results are achieved with Neem when it is used in mixture with a very pure spraying oil such as Grosafe Enspray 99and applied at first sign when insects are small.Enspray 99 improves coverage and adhesion of the Neem as well as killing eggs and young insects by smothering. For best results apply a second spray 5 - 7 days later, and for heavy infestations, a third spray a week or so later again.
Grosafe BioNeem, Naturally Neem, OCP Eco-neem and Grosafe Enspray 99 are all registered and approved for use on all edible crops, with no withholding period, so harvesting can continue.
These four products are organic and safe to bees and beneficial insects.
Grosafe BioNeem, Naturally Neem and OCP Eco-neem contain commercial strength levels of active ingredient and are used at 1 – 2 mls per litre of water.
Other brands of Neem are only approved for ornamentals. They have less than one third the active ingredient, requiring a higher rate of application which makes them more expensive per litre of spray mix. For the complete science background on Neem see our pro section (coming soon)
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