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Bacillus thuringiensis

If you have moths or caterpillars bothering your garden, Bt (or Bacillus thuringiensis) is your best bet to wipe them out without harming beneficial insects. You can buy this organic pest control at just about any garden or home improvement store.

If you have moths or caterpillars bothering your garden, Bt (or Bacillus thuringiensis) is your best bet to wipe them out without harming beneficial insects. You can buy this organic pest control at just about any garden or home improvement store.

Bacillus thuringiensis, commonly called Bt, is a naturally occurring bacteria that causes disease in moth and butterfly larvae. Sold in powder form, it’s an effective organic insecticide for tomato hornworms, cabbage worms and other worm-like garden pests.

Unlike typical insecticides that affect the insect’s nervous system, Bt acts by producing proteins that react with the cells of the digestive lining of certain insects. Bt proteins paralyze the digestive system, and the infected insect stops feeding within hours. Bt-affected insects ultimately die from starvation, which can take several days.

Bt is generally applied to plant surfaces as a powder. You just sprinkle it on, and as worm pests feed, they will also ingest Bt. Bt is a great option because it is free of synthetic chemicals and harmless to humans. One disadvantages is that it washes away with water, so after irrigation or a rainstorm, you may need to apply. In addition, it is harmful to all moth and butterflies, so it could kill the beautiful Monarch butterflies if they decide to land on and eat your plants.

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