A safe and responsible approach to curbing pests and diseases starts with good garden practices. Good gardening practices, like building healthy soil, encourage vigorous plants that are less susceptible to disease and pest problems. To keep healthy soil, repeatedly add organic matter, including green manures. This will improve the soil and lead to more vigorous plants.
Also, make sure you plant at the proper time – http://www.agroconection.com/soil/what-is-good-soil/. Seeds sown too early or transplants set out too soon are often subject to stress. Stress weakens the plants and makes them more susceptible to disease and pests. Provide the right conditions. Give your plants the amounts of light, moisture, and nutrients they need. Avoid wetting your plants in late afternoon or evening, so that the leaves don’t remain wet all night. Many fungal diseases are spread in water droplets, and wet foliage aids in their spread. Torn leaves, broken branches and disturbed roots are also an invitation for diseases and pests to attack your plants. Handle your plants gently when working around them. Inspect all plants for signs of disease before you buy. Keeping your soil covered with mulch will reduce weeds and will slow the spread of fungal and bacterial disease.
Don’t forget to practice good housekeeping. Keep your garden weed-free; and remove plants that are diseased or seriously infested with insects promptly. Remember, watch for problems, and take steps to control them before they get out of hand. Unfortunately, even the best garden practices are no guarantee against insects and diseases. But there are some other things you can do that can be used effectively to grow healthy vegetables and herbs. Trap cropping is using another plant to lure insects away from your vegetables and herbs. Some trap crops and the pests they attract are as follows:
- Nasturtiums attract aphids
- Smartweed attracts corn earworm
- Radish or turnip attracts the cabbage maggot
- Bok choy or Chinese cabbage attracts flea beetle
- Borage, evening primrose and white geranium attracts the Japanese beetle
- Castor bean attracts the nematode
- Hosta attracts slugs
- Dill attracts tomato hornworm
There is evidence that some plants actually deter insects. Asters, calendulas, geraniums, and marigolds are believed to deter most pests. Some other plants believed to have insect-deterring abilities are as follows:
- Borage repels tomato hornworm
- Catnip repels flea beetles
- Garlic deters aphids and Japanese beetles
- Mint repels aphids, Cabbage moths and Colorado potato beetles
- Sage deters cabbage moths and carrot rust flies
- Tansy deters cucumber beetles, Japanese beetles and Squash bugs
- Wormwood repels carrot rust flies, cabbage loopers, and flea beetles.
Use of the trap cropping and insect-deterring plants is also known as companion planting. These methods are quite useful if you are like me and don’t want to be using chemicals all over your gardens. Besides there are some beneficial insects and the chemicals don’t differentiate between bad and good insects. I’ve used companion planting for the past several years very successfully. I not only have good harvestable crops, but I also have interesting gardens with all the different plants used together.