Benefits of Neem Effect on Beneficial Insects
Neem as a Fungicide How to Apply Neem Oil
Neem oil aka Bioneem is a safe, eco-friendly non-toxic pesticide and fungicide for use by home gardeners. It is a non-chemical alternative acceptable in organic gardens, and for commercial applications.
7. It has the added benefit as being a useful fungicide.
8. It is virtually harmless to beneficial insects.
It can be safely used on food crops without fear of harmful residues. It breaks down naturally in the soil and will not accumulate to toxic levels as chemical pesticides and fungicides are known to do. It is approved for use on Food Crops and effectively controls more than 300 pests.
Neem comes from a fast-growing broad-leaved evergreen. Neem trees also known as azadirachta, Nimtree, and Indian Lilac are indigenous to Southern Asia, Africa, and Australia. In recent years they have been successfully grown in areas such as Florida and South America.
Neem oil as a foliar spray is most effective when applied to younger plants. The oil, being a natural compound biodegrades faster than man made chemicals, its effectiveness is limited to 3 - 4 days and needs to be frequently re-applied. It is water soluble, however, When diluted with water it's effective span is drastically reduced so it is best used straight or with minimal dilution. Actually, The highest concentration currently available to home gardeners is about 3%, so product packaging should give information on dosage.
Some Garden Gurus have suggested using Neem Oil as a soil drench. Take note that Neem oil is not a systemic insecticide. It is similar to a contact killer but must be ingested by the insect to be effective. Because many beneficial Bugs , such as Bees and pollinators don't ingest sufficient foliage, they aren't effected.
As a soil drench, it is not very effective against insects. Theoretically, the neem enters the plant's vascular system, insects ingest it during feeding. In reality, by the time the compound works it way through the soil, into the plants vascular system and than into the bugs it's effectiveness is long since expired.
As a foliar spray it causes insects to reduce or cease feeding, will prevent larvae from maturing, interrupts mating and egg laying. If sprayed directly on the insect, like other horticultural oils it coats their body surface, prevents respiration and hence kills them.
Neem oil fungicide is useful against fungi, mildews and rusts.
It is suggested commonly as an effective fungicide primarily for the prevention of various fungal and bacterial diseases such as
mildew and scab
The alkaloids Nimbin and Nimbidin found in Neem have strong anti-viral as well as anti-fungal properties. There are better more effective products on the market in the realm of fungal and bacterial protection, however - If you are already using neem, or plan to use Neem for insect control, it has the added benefit of serving as a fungicide. If you already have fungal problems closing the door once the animals are out is not very useful. Neems primary benefit is as an insecticide not a fungicide. It is also more useful as a preventative measure rather than a cure for existing fungal problems.
Other limitations on neem as a fungicide is that it breaks down rapidly in nature. Extremes of temperature, rain and other environmental factors make it necessary to reapply it frequently.
Baking soda aka sodium bicarbonate is a cheap and effective fungicide it is used for controlling powdery mildew and other fungal issues. See: Baking Soda Natural Fungicide. Combined with Neem oil the two compliment one another's effectiveness.
1 gallon water
10ml neem oil
10ml soap (Dawn, Ivory or castille soap)
2 tsp baking soda
Do not rely too heavily on persistent use of baking soda, its sodium component will accumulate in the plants and soil, over time it can become toxic to plants.
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