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Watering Basics for New Trees
- In Central Virginia new trees (those planted in the last 2 years) need to be watered from spring through fall the first two years after planting.
- To determine if your new tree needs water check the soil. If the soil is dry about 3 inches deep and near the tree it’s time to water.
- Watering frequency:
- Ideal – water once a week un less there has been at least an inch of rain.
- Good – every two weeks
- Minimum, not recommended– every 3-4 weeks. This will reduce mortality during a typical summer, but may not produce the healthiest tree. New trees in hot locations or any new tree during very hot, dry weather will likely die.
- Realistic – if you cannot water once a week, water as often as you can manage and then water once a week when the weather is very hot and dry.
- At least 15 gallons of water should be applied each time you water. (Newly planted bare root trees will not need this much water since their root balls are much smaller than those of larger trees obtained from nurseries. Still, they need sufficient water to get down to the roots.)
- Lawn watering systems are intended to provide enough water take care the grass which has shallow roots and will probably not provide enough water to get to the roots of trees, so don’t depend on this to water your tree.
- These are general guidelines. There are many variables – soil type, planting location, tree species & season planted – that will influence watering needs. Trees in full sun, those near pavement or other hot spots will need more attention than others.
Summer Dos, Don’ts and Tips for Trees
- Do use organic mulches (wood chips, bark, etc) to conserve soil moisture and moderate soil temperature. Mulch should be 2 -4 inches deep and should never touch the trunk of the tree.
- Do not use inorganic mulches such as stones.
- Do pay more attention to trees near pavement or other hard surfaces since these trees experience more heat than those in the middle of a yard or landscaped area. These trees may also receive less water when it rains, since much of the water runs off rather than soaking into the ground.
- Do water slowly so the water soaks into the ground rather than running off.
- Deep watering is essential!
- Do not give small amounts of water. Even if this is done often, it does more harm than good. This encourages shallow roots that dry quickly.
- The best time to water mature trees is between late evening, at night , or very early morning. Trees replace the water they have lost during the day at night. Watering at night also reduces the amount of water lost to evaporation.
- Do not use fertilizers around trees during drought and be very cautious about the use of pesticides.
- During drought and water restrictions, give trees priority over lawns. It takes many more years to grow a tree than a lawn. A lawn can become dormant and, if necessary, can be replaced in a season; it could take a lifetime to replace a large tree.