Vegetable Disease Recommendations for Home Gardens

Disease Management

Vegetable diseases can severely limit productivity of the garden. Some vegetable diseases can be serious problems every year, while others may rarely appear in the garden. Soil-borne diseases such as Fusarium, Phythium, Rhizoctonia and Phytophthora can survive in soils for many years, and once established can be very difficult to get rid of. Therefore, proper crop rotation is very important for controlling soil-borne diseases in the home garden. Other diseases, such as powdery mildews, are wind-borne (aerial) and can cause problems anywhere your garden is located. In both cases, whether the disease is soil- or wind-borne, good cultural practices and prevention are critically important for maintaining a healthy garden.

Frequent monitoring of the garden to detect problems at an early stage and good cultural practices will allow you to prevent or reduce disease development. However, for effective monitoring, the homeowner must know where and when to look for vegetable diseases and be able to identify those that are found. Rutgers Cooperative Extension offers fact sheet FS547, Diagnosing and Controlling Fungal Diseases of Tomato in the Home Garden, with information about important diseases of tomatoes in the home garden. Remember, without proper identification, disease management is impossible.

Keys to Effective Management

1. Rotate the entire garden to a new location as often as possible. This is especially important for reducing the chances for soil-borne diseases to develop. If the same location is used for more than one season, rotate the crops within the garden by plant family. Garden rotation is highly effective in reducing soil-borne disease problems.
2. Plow or turn the soil well in advance of planting. The garden should be well plowed and free of weeds, grass, etc., at least 30 days before planting.
3. Buy seed or vegetable transplants with known resistance to common diseases. In many cases, catalogs or tags will list pathogens that plants are resistant to. Transplants should be purchased from a reputable dealer and should be free of disease and insect pests at the time of planting.
4. Follow recommended plant spacings and practice good weed control to maximize air movement through the garden to encourage rapid leaf drying. Use proper fertility and watering programs to maintain plant health and vigor.
5. If possible, use a soaker hose or hand water at the base of plants. Never run your sprinkler in the late afternoon or evening! Long hours of leaf wetness results in ideal conditions for disease development. If you need to water with a sprinkler, do so in the morning or early afternoon so leaves have enough time to dry out before sunset.
6. Learn to identify common garden diseases, know when and under what conditions they are likely to occur, and consider chemicals only when a disease problem exists. Seek alternatives to chemicals when possible.
7. Thoroughly inspect plants at regular and frequent intervals to monitor any potential disease development. It is suggested to scout the garden at least twice a week. Inspect plants carefully from top to bottom, including both upper and lower leaf surfaces.
8. Harvest fruit, seed, pods, etc., as soon as they are ripe. Allowing overripe fruit to remain on the plants often invites additional pest problems.
9. Once a plant is no longer productive, destroy it or plow it under or remove it from the garden. Avoid pulling infected plants up and leaving them in the garden area. Infected and/or dead plants left in the garden will only act to harbor the pathogen and potentially cause more disease to develop.
10. It is recommended that you do not use infested vegetable plants in any form to add to a mulch bed or compost bin. Vegetable plant matter can harbor insects, disease organisms and nematodes that can easily survive organic decomposition and cause future problems, especially if not composted properly.

^* Some formulations of these products may be considered organic, be sure to check the label.

^1. Active ingredients, not product names, are listed. Pesticide products and formulations may change. Always follow label instructions. Check label for personal protective equipment, number of applications allowed per season, interval between sprays, and the number of days between last spray and harvest.

March 2026