Disease management in the home vegetable garden
One favorite hobby of many Gordon County residents is vegetable gardening. Vegetable gardening can be a fun and rewarding activity. In addition, gardening can also be a healthy chore by getting folks outdoors and activity. The rewarding part is when you can provide fresh vegetables for your family and friends during the growing season. One issue that can dampen the joy in vegetable gardening is when disease becomes a problem. Today, I will be sharing tips on disease management from a revised UGA publication by Elizabeth Little, UGA Home Garden and Small Farm Plant Pathologist.
When we think about disease in our vegetable garden, we mainly are thinking in terms of our warm season gardening efforts. We seem to have more disease issues in wet and warm weather patterns.
The four primary types of organisms that cause plant disease issues are fungi, bacteria, nematodes and viruses. The organisms are grouped into what we call plant parasites or pathogens. You see issues with fungi and bacteria more when you have more moisture from rain and dew along with warm temperatures. Virus issues are more of a problem in summer when the insect pressure that carry the diseases are higher. Nematodes are more of an issue when temperatures are warm, but they can feed on plant roots year round. You can’t see the actual root damage, but you will see less plant production and plant growth issues.
The first tip in disease management in your vegetable garden is simply site selection. You need an open and sunny spot to grow vegetables. The area needs to be a great well- drained area too. Too much soil moisture can lead to root and crown diseases. A sunny area will allow for quicker drying of the foliage in wet times and should reduce the number of foliage diseases. Another tip is crop rotation.
Do not plant the same vegetables in the same spot in the garden each and every year. Planting in the same spot can lead to pathogen buildup. It is suggested to only grow the same type of vegetables or closely related vegetables in the same soil once every three to five years. When you incorporate rotation into your efforts, you will reduce the pathogens that can cause your stem and leaf diseases.
If you are having issues with some of the soil borne diseases, you may need longer rotations and maybe other management methods.
Another tip is to use disease free seed and healthy plants. Keep in mind that some diseases are seed- borne issues so if you want to save seed, consult seed saving guideline for information on which species or cultivars are suggested. Do not save seed from unhealthy plants. Many seed companies will treat seed with fungicides that will provide some seed protection. This treatment mainly will protect germinating seed and young seedlings, but will not protect the plant after the seedling stage. You can also use more diseaseresistant varieties in your garden. When you are doing your variety selection, many seed companies will list the resistant traits of that vegetable variety. You can study up on some of the more problematic disease issues for the Southeast and find varieties that have some resistance for that issue. Keep in mind that when we talk resistance it can be a total or only partial resistance depending on the disease and the variety in question.
Planting date management is also a consideration in disease management. Traditionally, the middle part of April is about as early as I would consider planting warm season vegetables. Many experienced growers will wait till later April and even May to plant their gardens. It is a fine line of success or failure when you plant a garden too soon. You can have problems with late freezes and soils that are too cool and wet which can lead to stunted plants and disease. Some items such as corn and squash may do better if they get up and going early to reduce interference with pest issues.
As I wrap up today, keep in mind that proper spacing and incorporation of trellising can help in disease management. Mulching can help reduce soil pathogens from splashing on plants and can keep fruit from touching bare soil. How and when we irrigate our gardens can be a big issue in disease reduction also. Managing weeds plus keeping the pH correct along with proper fertilization can help too. For more information, contact UGA ExtensionGordon County at 706- 629- 8685 or email gbowman@uga.edu.