Vegetable garden needs deep watering

Q: How often should I be watering my vegetable garden?

Answer: The frequency and amount of water your vegetable garden will need is going to depend on the weather conditions we are having. It is usually very hot during late June, into July and August, so the general rule of 1 inch of water a week may not be enough. The best way to tell if your plants are receiving enough water is to take a trowel or shovel and dig down a few inches after you have watered or after a rain. The soil should be moist at least 3 to 3 to 4 inches deep to ensure that the water is reaching the root zone of the plants. The primary rule of summer watering is to water thoroughly and deeply each time and to allow the soil to dry out a bit between watering. Deep watering will allow the plant's roots to grow deeper as well as the added benefit of anchoring the plant better into the ground. Light surface watering actually wastes water, because the water never reaches the root zone for uptake by the plants. Soil temperatures are high this time of year and soil moisture evaporates rapidly from the top inch of soil. Try to do your watering in the morning hours when air temperatures are cooler and more of the water will be taken up by the plants. It is best to water at the base of the plants so that you avoid wetting the foliage. Wet foliage makes plants more susceptible to fungus and diseases. A soaker hose makes a great way to water the vegetable garden. Place a rain gauge out near the garden so that you can better monitor rainfall. If we are getting sufficient rainfall each week, say 1 to 2 inches, you may not need to supplement with irrigation, unless we have extreme heat. Plants lose water through their leaves in a process called evapo-transpiration. As temperatures warm, evapo-transpiration speeds up, increasing the water demand for plants.

Q: Is it safe to use water from our rain barrel in our vegetable garden?

Answer: Keep your rain barrel water refreshed by using it throughout the summer. When rain-barrel water stands, especially in warm weather, there can be some potential bacteria growth from any animal feces that have washed into the rain barrel. With that in mind, it is safer to use potable water in the vegetable garden. But if you choose to use your rain barrel in the vegetable garden, water the soil around the base of the plants and not the plants themselves. Never wet any edible portion of the plant with water from a rain barrel and always wash your produce with potable water before you eat it.

Mary Jac Brennan is the agent for fruit and vegetable horticulture for small farms and local food for the Forsyth Cooperative Extension. Contact Mary Jac about commercial production, local foods, and sustainable agriculture questions. For information on home and gardening issues, contact the Forsyth Cooperative Extension office at maryjac_brennan@ncsu.edu or call 336-703-2850.

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