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Growing Your Own Growing Your Own Vegetables | Composting | Container Gardens | Fall/Winter Gardens | Fertilizing | Insect Pests | Plant Diseases | Planting Guidelines | Raised Beds | Regional Tips | Site Selection | Slugs | Soil Improvement | Tilling | Warm-season Crops | Watering | Weeds Watering Vegetable Gardens Methods of watering How often to water Watering mistakes to avoid Plants that receive the proper amount of water are likely to be healthy and productive. In Oregon, summer vegetable gardens require regular watering because of the extremely low rainfall during that season. When planning your garden, consider how you will meet the plants' water needs. Soil type is an important factor in watering. Water soaks into and drains through sandy soil approximately twice as fast as it does clay soil. Loam soil lies between these two extremes. Thus, it takes longer to water to a specified depth in clay soil. Methods of watering There are three basic watering methods: hand watering (with a hose or a watering can), soaker hoses and drip irrigation systems, and portable sprinklers. The method you choose will depend on the size of your garden, your budget, and your life style. Hand watering delivers water directly to the plants, thus eliminating waste. If you are hand watering, be sure to water deeply. Remember, this takes time. Do some spot checks to make sure you are delivering enough water, and be careful to give all areas of the garden adequate coverage. Enlarge illustration Drip irrigation systems require an initial investment of time and money, but, once installed, are more convenient and conserve water. You can set up a drip system to meet the needs of individual plants precisely and then alter it throughout the growing season as watering needs change. As with any watering method, infrequent, deep watering is the goal. A typical drip system is run 1 or 2 hours once or twice a week. Avoid the tendency to overwater with drip systems; the surface may look dry while the rooting zone is wet. If in doubt, check the soil. The pattern of soil wetting with drip irrigation is different for sandy and clay soils. In sandy soil, the water soaks straight in, wetting a narrow vertical band of soil. In clay soil, the water spreads more horizontally. Thus, drip emitters can be placed farther apart for clay soil than for sandy soil. See an animated example. Sprinklers have the disadvantage of wasting water by watering paths and other bare spots in the garden. They also lose water to evaporation and wind drift. When using sprinklers, always water when there is little wind. Because they wet the foliage, sprinklers also might promote the development of leaf diseases. If using oscillating sprinklers, elevate them above the tallest plants so the water streams are not blocked. To make sure all of your plants are watered, place sprinklers so their patterns overlap. Runoff indicates you need to water at a slower rate. How often to water Regardless of the system you choose, the goal is the same: to deliver water to the roots of the plants at about the same rate that it is removed from the soil by the plants and evaporation. Consider your soil, your plants, and recent weather when determining how much and how often to water your garden. Sandy soil holds much less water than clay soils. Larger plants consume more water than seedlings. Hot, windy weather dries out the soil. Instead of developing a watering schedule based on calculations and charts, monitor your garden to determine your watering needs throughout the growing season. Different plants in your garden may have different needs. Germinating seeds and seedlings need to be kept uniformly moist without being washed away, so water them with a gentle spray every day or two. Developing plants need to be watered deeply, but less often, to encourage deep root growth. Water to a depth of at least 6 inches and then let the surface inch or two completely dry out before watering again. Crops such as lettuce, beets, green beans, and chard draw water from the top foot or less of soil. Thoroughly soak the rooting zone and then don't water until the plants show signs of needing additional water such as turning a dark bluish green or wilting during the hottest part of the day. Corn, tomatoes, asparagus, and rhubarb have deep root systems that allow them to draw water from the top 2 feet of soil. Deep-rooted plants need water less frequently, but need more water to reach the rooting depth. As a general guideline, garden plants that have been watered properly, and therefore have developed deep roots, need a thorough watering every 5 to 7 days in hot weather. Avoid these three common watering problems Frequent, shallow watering promotes root development in the surface layers of the soil. Plants with shallow roots are very susceptible to drought Overwatering can drown plants by filling up soil pores with water, leaving little or no oxygen for plant roots. Also, excessive watering leaches away nutrients and can contribute to groundwater contamination. Postponing irrigation after plants show signs of needing water can damage plants very quickly in hot weather. Observe your plants every day or two and respond to their needs promptly.

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