Organic is a word that people are very interested in these days, especially in the lawn and garden category. Electing an organic route can limit your options. One choice that you may not find on the shelf is beneficial nematodes.
Beneficial nematodes should be your first line of defense. Think of it as preventative care. You can treat a problem after you see it on the surface, but it is more effective to treat before it emerges. Beneficial nematodes are microscopic parasites that thrive on insect larva. There are over 20,000 known species of nematodes. In one hand full, you would find thousands. Some are beneficial. Others are not.
Steinernema and Heterorhabditis are two commonly used species. They invade and kill garden pests such as grubs, fleas, mole crickets, Japanese beetles, weevils and more. Beneficial nematodes dwell in most any soil, but flourish in moist. Since nematodes are small you will need to introduce high numbers to make a strong impact. For example, in a 2000 square foot space, you will want to bring in about one million nematodes. You can use that same ratio to calculate numbers for any space.
You will find that nematodes are sold in packets and can be stored in the refrigerator for a few weeks. When you are ready to apply them just mix with water, and pour them into the soil with a watering can.
Indoor and greenhouse plants can also enjoy the benefits of nematodes. Common problems are gnats and fungus. Beneficial nematodes will eliminate both problems.
Check with your local garden supply store, and online for pricing and availability.