Question: How should I properly water my vegetable garden?
Answer: Do not stand in the garden and water lightly. This is the worst possible method of watering vegetable plants. When you do water, water thoroughly to encourage plant roots to seek moisture and nutrients deep in the soil. Soak the soil to a depth of 6 to 8 inches.
A thorough soaking every five to six days is usually sufficient. Of course, weather conditions such as temperature and rainfall also will affect frequency of watering.
Use soaker hoses or drip irrigation for best results, as overhead watering is usually a very inefficient way to water. Soaker and drip irrigation places the water near the plant's roots and not in the middle of the rows. Also, soaker and drip systems do not wet the foliage, thus helping to reduce leaf spot and other diseases.
Q: Why do my vegetable seedling plants turn black and rot at the soil?
A: It is a common fungal disease called damping off or pythium. This disease is usually caused by overly wet soil conditions.
Pythium attacks the lower stems of young vegetable and flower plants, causing the stems to rot at the soil line. Keep the soil moist but not overly wet, and treat the seed and seedlings with a recommended fungicide at planting.
Q: I fertilize my vegetables regularly and the plants look great, but I have little fruit. Why?
A: Heavy amounts of fertilizer, particularly high nitrogen fertilizers, cause plants to produce foliage at the expense of fruit production.
Fertilize vegetable gardens during the growing season according to soil test recommendations. Use fertilizer at planting time, and side dress as prescribed by the soil test.
For any vegetables that produce fruit (tomato, pepper, potato, onions, carrots, broccoli) use a 1-2-3 analysis fertilizer (for example, 5-10-15, 4-8-12) and for leafy vegetables (lettuce, all greens) use a 1-1-1- analysis (for example, 8-8-8, 10-10-10).
Q: My squash plants are covered with a white, powdery substance? What is it?
A: Powdery mildew is a common fungus disease that attacks many plants. This disease thrives in hot, humid weather and spreads from plant to plant by spores. Powdery mildew infects plant tissue causing yellowing and sometimes death of plants.
Remove infected leaves, treat plants with recommended garden fungicides such as Daconil or use organic controls such as neem oil. Also, select and plant powdery mildew-resistant plants.
Q: I found several old bottles of vegetable insecticides and wonder if they are suitable to use? How old is too old?
A: The answer to this question is, it depends. Stored under ideal conditions, many pesticides can effectively last for many years. Ideal conditions include being kept out of direct sunlight in a cool, dry location with the lid or top securely closed. Too much cold or heat lessens the shelf life of most pesticides products.
If the products you found appear to be usable - that is, not hardened if in a powder form or separated into layers if in a liquid form - you may wish to apply the product according to label directions to a test plant or location before applying to many plants or over a large area.
Try to purchase pesticides in amounts that will last for two to three years.
Billy Skaggs is an agricultural agent and Hall County extension coordinator. Phone: 770-531-6988. Fax: 770-531-3994.