Fruit Tree Care
By: National Gardening Association Editors
Once your trees are planted, here's how to keep them growing strong and producing an abundant harvest.
Water and Mulch
During the first two growing seasons, water the trees deeply (6 to 8 gallons of water per tree) about once a week if there's been little or no rain. Don't apply less water more frequently. That will encourage shallow rooting.
Irrigate bearing fruit trees if they receive less than 2 inches of rain during any 2-week period between bloom and early fall. If no rain has fallen for 2 weeks, this means you need to add 1 gallon of water per square foot of rooting area, which extends several feet farther out than the tree's dripline. Measure rain and sprinkling systems with open containers on the ground. The most critical time to water is during fruit expansion, but don't apply more than 2 inches. Excessive watering can cause fruit to expand too much and be more prone to rot.
Spread 4 to 6 inches of mulch around the trees to their dripline to conserve moisture and control weeds. You can use bark mulch or other attractive mulches and plant noncompetitive flowers (spring bulbs and shallow-rooted annuals) around the trees. Before spreading straw mulch, let it sit out and wet it several times to encourage weed seed germination.
You can grow a lawn or other groundcover between the mulched areas around the trees, and the mowings can be used for mulch. You might plant quick-growing annual cover crops such as buckwheat and annual rye during the first few years to provide organic matter, but as the trees get older, you'll need to establish a permanent groundcover. Legumes such as bird's-foot trefoil (with yellow flowers) or crimson clover (with red flowers) make attractive groundcovers where they are adapted. Mow grasses to reduce competition, and mow legumes frequently to reduce stinkbug injury. Groundcovers that don't require mowing include wildflowers and noncompetitive evergreens such as vinca minor and creeping phlox. Avoid warm-season grasses such as Bermuda or zoysia, and competitive groundcovers such as pachysandra. Ask your nursery for other recommendations for your area.
Supply fertilizer and abundant organic matter during the first few years to get the trees off to a good start, but keep in mind that heavy or careless applications of fertilizer can damage the trees. To avoid burning the new root system, wait 6 weeks after planting to fertilize. Then apply a fertilizer containing 1/10-pound of actual nitrogen in a wide band 1 foot out from the trunk. It's best to apply a nitrogen source separately and adjust phosphorus and potassium according to soil test results, although a complete fertilizer can also be used. You can apply nitrogen in any form as long as it equals the specified amount. Don't plan on supplying all of a young tree's nitrogen needs with compost or manure. If you added enough to do that, nitrogen would still be released in early fall, inducing the tree to grow too late in the season and predisposing it to winter injury. During the summer, check the amount and color of growth to guide you in fertilizing next year. Leaves should be dark green and terminals--the shoot growth from the sides or end of a branch--should grow 16 to 20 inches during the season. If trees received adequate water but leaves are yellowish and terminals didn't grow that long, add more fertilizer next year. If terminals grow 22 inches or more, cut down on fertilizer.