Neem Oil Insecticide and Fungicide

Neem Oil Insecticide

Neem oil solidifies even at room temperature. Mixed with water, it's a sprayable form and is easy to use to saturate the entire plant.
BioNeem® is a neem oil insecticide that's particularly effective. You can use it to safely treat your house plants for mealybugs, aphids, whiteflies, thrips and fungus gnats. It kills many other bugs, too. However, these are the most commonly found on indoor plants.
How it works. Neem oil doesn't instantly kill the insects. It causes them to lose their appetites so they starve to death. It also reduces female fertility and inhibits reproduction. Usually, 2-3 applications are necessary, to affect every life stage.
How to use neem oil. The product is mixed with water and sprayed directly on house plants. Spray the stems and undersides of the leaves as well because that's where most bugs hide. Also spray the surface of the soil because many insects lay eggs in the soil. You want to get eggs and larvae, too.
Read and follow all directions and precautions on the product label before using any insecticide.

Neem Oil Fungicide

Many tests have shown neem oil to effectively control black spot, fungus and powdery mildew -- common problems that sometimes affect house plants, especially ivy and flowering plants.
Spray leaves with neem oil mixed with 2 teaspoons of baking soda. Although this treatment won't get rid of fungus already on the plant, it will prevent the spread of fungus and mildew.