Autumn is a Perfect Time to Plant Trees

If you think spring is the only time to do major work in your yard, you just may be surprised. Fall is actually the perfect time to work on landscaping, says Dr. Ken Tilt, an Alabama Cooperative Extension System horticulturist.

"Fall is really an ideal time for planting," he says. "It isnít the only time for planting, but itís definitely an optimal time because after you get a few frosts, the plants go dormant and are less active. However, we still have soils that are warm enough throughout the winter that we get root growth. So by planting in the fall, you are planting in the cooler time of the year, and you get root growth that will be ready to take up water during our hot spring temperatures. When leaves unfurl and expand, the increased roots are better able to access the reservoir of water, and the stress of transplanting is drastically reduced.

Tilt says fall is the best time to plant bare-root plants and some types of roses and perennials.

"Some of the perennials that come in through catalogs are shipped without any soil on the roots and need to be planted in the fall," he says. "You should put them in water as soon as you get them, soak them for about 24 hours, and then plant them. If you canít plant them immediately, put them in a shaded spot with some moist soil around the roots so the roots donít dry out. The roots are the most important part of the plant; donít let them dry out. If they die the shoots will come out the next year, but with no water uptake they will quickly wilt and die."

Tilt says two traditional ways of planting trees in the fall are the balled-and-burlapped method and planting from containers.

"With the balled-and-burlapped (method), nurseries dig these plants out of the field and then transplant them during the dormant season Ė sometime between late October through early March," he says. "When you dig the trees or shrubs, up to 90 percent of the roots are removed. So that puts the plant under a lot of stress. Nursery workers have been using this harvest method for hundreds of years, and it works well. But you have to realize the plant is under stress. So the best time to plant those is through the dormant season."

Container plants are also popular. "You can plant these year-round, but fall is a nice time to plant them, too," he says. "If youíre planting those in the heat of the summer, you have to be careful to give them enough water. Theyíre all grown in a pine bark substrate or medium thatís very open and porous. And when you plant those into a clay soil, which has a finer texture with different water properties, it will actually draw the water away from the pine bark medium. As a result, the plant will dry out faster than a balled-and-burlapped plant. You can plant from containers as long as you keep up with the water needs of the plants."

Tilt says a good oak to plant this fall is the overcup oak, which tolerates a wide variety of soils and is a good choice for Alabama gardeners. Other great trees to plant this fall include the Chinese pistach, the Chinese fringe tree and a disease-resistant type of dogwood called the Cherokee brave.

"A mid-sized tree that has given us the best fall color that weíve had in the landscape with few problems is the Chinese pistach," Tilt says. "Theyíre all grown from seeds, and they have a range of fall colors from yellow to orange to red. It has consistently produced great fall color and is a tough plant, so itís good for urban sites."

The Chinese fringe tree is a small flowering tree that many people enjoy. "It has a glossy leaf and beautiful puffy white flowers in the spring," he says. "It is a tree people donít use much, but when they use it theyíre really excited about it."

In recent years, dogwoods have been particularly susceptible to powdery mildew, Tilt says, which has caused problems for gardeners. "Thereís one cultivar that is resistant to powdery mildew called Cherokee brave," he says. "Itís a red dogwood, and itís nice to have if you can find it."

When planting trees this fall, remember to dig a wide hole, not necessarily a deep hole.

"In the old days we recommended that you dig a real deep hole and fluff up the soil and plant the tree," Tilt says. "But we know now that most of the roots on the trees grow in the upper 12 to 18 inches of soil, and they spread out two to three times the canopy of the tree. So itís more important to dig a wide, shallow hole. The greatest cause of death of newly planted trees is planting them too deep. So dig a wide, shallow hole two or three times the size of the root ball so the roots can spread out."

Tilt says if the tree has burlap around its ball, donít remove it. Instead, peel it back and drop the excess material into the bottom of the hole. Fill in the hole around the plant with the same material you removed when digging the hole.

"Donít go to a lot of trouble to put in peat moss or compost in with that soil," he says. "Research has shown plants actually grow better if theyíre planted in the same soil you dug it out of. Make sure that you mulch with 2 or 3 inches of some type of pine straw or compost or some kind of organic material. Water it thoroughly to get rid of air pockets and so it has a good supply of water."

Tilt also recommends taking soil tests before planting anything. "You may have to amend the soil with some lime," he says. "Add a little bit of fertilizer thatís not high in nitrogen. The tree needs to put out roots initially. If you put too much nitrogen on the plants, youíll get too much top growth at the expense of root growth."

For more information about taking soil tests or planting trees this fall, contact your local county Extension agent.

SOURCE: Dr. Ken Tilt, (ktilt@aces.edu), Extension Horticulturist, Alabama Cooperative Extension System, (334) 844-5484