10 Tips for Preventing Most Garden Diseases

Too many gardeners struggle with garden diseases. Most gardeners will probably see damping-off or powdery mildew at some point. Unfortunately, others may face viruses and bacterial problems that are difficult to eradicate.

The good news is that there are simple steps you can take to avoid introducing and spreading plant diseases in your garden. The following steps are proven ways to keep your garden healthy:

1. Grow your own seedlings. Unfortunately, buying seedlings is one of the best ways to bring new diseases onto your property. Diseases may be carried either on the plant itself or in the soil. Growing your own seedlings is one of the most effective biosecurity measures you can take.
2. Buy seeds from quality sources. Likewise, choose seeds carefully, as a few diseases can be transmitted by seed. Be very cautious when buying seeds online, selecting only sealed packets from reputable companies.
3. Let there be light. Maximizing sunlight throughout the garden is one of the most effective ways to keep pathogens in check. Choose a garden site that gets full sunlight throughout the day, if possible. Prune trees and shrubs to ensure that light can access most of the plant. Also space plants appropriately, so that shorter plants are not shaded out by taller ones (except maybe in summer to extend the life of cool-season vegetables). Consider growing vines vertically on trellises and other support structures.
4. Promote air circulation throughout the garden. Likewise, make sure air can move freely throughout the garden during the growing season. A windbreak on the north side of the garden may be beneficial, but otherwise you generally want the breeze to access all parts of all plants. (This is why commercial grape-growers often put large fans in the vineyard.) Prune accordingly, both trees and bushy plants like tomatoes.
5. Keep tools clean. Many pathogens are carried on garden tools. If there is any risk of disease in your garden, regularly sterilize your tools with a bleach solution. When pruning trees, this usually means after every cut.
6. Avoid excess nitrogen. Nitrogen is necessary for plant health and growth, but too much nitrogen promotes the rapid growth of soft tissue that is easily damaged, allowing pathogens to enter the plant. Avoid the use of nitrogen fertilizers whenever possible, opting instead for mulches, compost, cover crops, and well-rotted manure.
7. Water just enough, but not too much. Letting your plants go without water is a major stressor, which can give diseases a foothold. On the other hand, soggy soil and dripping leaves constitute fungal paradise. The solution is to water plants deeply, allowing the surface of the soil to dry out between waterings. Building soil organic matter levels will help, too, by evening out the moisture supply.
8. Control weeds and pests. Weeds can harbor disease, and pests can infect plants with pathogens. Control weeds with mulch and hand-pulling. Pests can be kept in check by paying attention to overall plant health and by removing potential habitats.
9. Remove all dead or dying plant matter. Allowing plant debris to accumulate promotes pathogen growth. Throughout the growing season, prune off dead or damaged leaves, and pull up plants that are past their prime. Also be sure to clean up dead plants after frost kills the garden.
10. Compost only safe materials. If you suspect that a plant was diseased, don’t put it or any part of it in the compost. Burn it, bury it away from the garden, or put it in the dumpster safely sealed in a plastic garbage bag.

Aside from these steps, monitor your plants regularly. Healthy, vibrant plants rarely get diseases. And they produce the tastiest food, too!