My motto for having a healthy garden is Feed the Soil and Build the Ecosystem. Feeding the soil results in healthier plants, thus healthier people who eat those plants. Healthy plans are better protected from insect predation. The first plants to succumb are the weaker plants with unbalanced nutrients.
It is good to mix things up a bit. If insects are looking for plants they like to eat, they will naturally be attracted to monocultures first. All the signals that plants send, through sight, smell, color, etc., are magnified in a monoculture. When plants are grown in a mixture, sometimes called a guild, the signals from so many different plants together confuse the insects. Information on companion planting suggests things to plant together. The three sisters—corn, beans, and squash—are an example of that practice.
Some of the things you can put in as companion plants are especially suited to attracting insects that will eat the larvae of the insects that want to eat your plants. There are charts available that will show what to plant to attract specific insects that will feed on the insects you want less of in your garden. However, if you follow some simple guidelines, those beneficials will begin to show up anyway. This is the “build the ecosystem” part of my motto.
The first guideline is to not use chemicals. They will kill the good insects as well as the bad. The next thing to know is to not till your garden all at once. Having permanent paths and permanent beds allows you to only have the soil exposed in whatever part of your garden you are working in at the time. The rest of the garden is left undisturbed, including the habitat for the beneficials. Also, the toads need somewhere to escape to. According to Sally Jean Cunningham in Great Garden Companions, one toad can consume over 10,000 insects, including slugs.
Another guideline is to let things flower. Don’t fret if your basil and sage flower before you have gotten every bit cut for culinary use. Enjoy the insects that come to feed on the nectar. Those are the same ones that will be keeping the harmful insects in check. If you have been following my work, you know that I plant a lot of cover crops. They flower in the natural progression of things and that’s where I often find beneficial insects.
The next guideline would be to plant specifically to attract beneficial insects. Some common suggestions are to plant borage with cabbage family plants and dill with your cucumbers and squash. Although you can look for specific plants, such as tansy, fennel, and mountain mint, having a mix of herbs and flowers in and around your garden will help. If you have spearmint growing, you know it can easily grow past its boundaries. Let it wander to an area you don’t mind devoting to spearmint and watch what happens when it is left alone to flower freely. The insects love it!
Permanent plantings, possibly in your borders, serve as good overwintering places for beneficial insects, as well as shady places for toad homes. You will find more ideas about attracting beneficials at Homeplace Earth. Once you understand what it would take to attract beneficials to your garden and work toward that end, you can relax and watch for them to come. Sit back and enjoy the show!
Cindy Conner is the author of Seed Libraries and Grow a Sustainable Diet and has produced DVDs about garden planning and managing cover crops with hand tools. Learn more about what she is up to at Homeplace Earth.