Plants that have their needs met (nutrients, water, a healthy ecosystem, etc.) are better at repelling pests. When the plants have what they need, they begin to produce their own organic pesticides. These are compounds that either prevent easy digestion, they are fully toxic, make them taste bad, or act as deterrents to pests. Here are some key ways to keep plants healthy:

1. Build Healthy soil

Growing splendid plants always starts with soil. If you have dead soil because you killed every living thing but your plant, the plant will not thrive. Each year you will have to add more and more fertilizer to get the same results. Building your soil takes time but if you stop tilling and start adding compost your soil becomes healthy over time.

Healthy soil = healthy plants.

Mulch helps protect and build soil, and so do compost and compost tea, actively aerated or not. These add nutrients and micro-organisms to the soil. Micro-organisms are important because they make nutrients “bio-available” to plants, breaking indigestible compounds down into nutrients the plants can use, while helping to build a healthy soil structure that keeps nutrients from washing away in the rain.

Building soil helps to create a pest free garden.

Add beneficial nematodes to the soil

2. Increase Soil Organic Matter

Mulch, compost, and the resultant micro-organisms will help to build the soil organic matter, which becomes a teeming-with-life underground ecosystem that feeds the plants and keeps them healthy while also dramatically increasing the soil’s water holding capacity. Other ways to increase organic matter are to plant mulch crops and periodically cut them and toss them onto the soil (e.g. comfrey, alder trees), and to plant “green manure” crops (e.g. alfalfa, rye, buckwheat), prior to planting, and then cutting them and working them into the soil a little (mixing the top layers of soil as little as possible with the lower layers).

  • Do not compost the effected plant debris
  • Dispose of infested plants

3. Rotate the crops

Don’t make it easy for the pests to find your plants by planting the same plants in the same spots year after year. Here is a simple order for rotating crops – legumes, leaf, fruit, roots. No one is perfect, do not keep it totally, just try to not plant the same thing in the same spot year after year.

4. Use Mulch

Mulch, which should be at least 4-6 inches thick, not only provides a habitat for allies like ground beetles, it also slows down water evaporation, breaks down into nutrients and protects the micro-organisms in the soil from the harsh sun, wind, and rain, while preventing soil erosion. You can mulch with leaves (but not from black walnuts), straw (seedless!), or wood chips (ideally not acidic ones like cedar), for example.