Is fall a good time to plant trees and shrubs?
A: It is the best time. Container-grown trees and shrubs can be planted 12 months of the year, but fall is considered the best time to plant them.
Why is fall the best time? Unlike the tops of ornamental plants that go dormant and cease growth for the winter, roots of ornamental plants continue to grow throughout the winter months.
Fall panting allows all the energy produced during the previous growing season to be directed to root growth because there is little demand from the top.
So when spring arrives, a well-established root system will be prepared to provide the necessary water and nutrients for optimum growth.
When you plant this fall, make sure you take the time to do it right, because improper planting is the biggest mistake many gardeners make in the landscape.
It is the number one problem at our plant clinic at the University of Georgia, and it is what all the garden center personnel complain about, particularly planting the tree or shrub too deep.
Probably 50-75 percent of dead shrubbery taken back to garden centers could be avoided if people planted correctly.
So avoid this common, yet so simple problem.
Although it would be desirable to cultivate or till a large area when planting a solitary tree or shrub, it may not be practical. Therefore when planting a single tree or shrub in native undisturbed soil, dig the planting hole two to three times as wide as the root ball. Simply changing the structure of the soil adjacent to the roots of the plant provides a favorable environment for early root growth and plant establishment.
In a study at the University of Georgia, a group of red maples were planted in soil that had been thoroughly tilled, while another group was planted in holes dug no wider than the root ball in undisturbed soil.
After five months, the roots of trees planted in the disturbed soil had grown 5 feet beyond the planting hole, while those in the undisturbed soil had only extended about 2 feet beyond the planting hole.
Dig the hole to the depth of the root ball and no deeper. This assures that the top of the root ball will be level with the soil surface and that it will not settle over time and become too deep in the soil.
When planted too deeply, the root system will struggle to obtain sufficient oxygen, plant establishment will take longer, and long-term plant stress may result. If the planting hole is accidently dug deeper than the root ball, backfill with some of the soil removed from the hole until the top of the root ball is level, or even slightly above the soil surface. Then firm the soil with your foot in the bottom of the hole to minimize settling.
Backfill with the same soil removed from the hole, breaking up clods to improve the structure of the soil. Organic amendments may be useful in improving excessively sandy or clay soil, however, if used, they should be incorporated into the planting area and not added directly to the planting hole.
Poor root growth and/or root rot can often result from this condition as water is held against the roots by uneven or irregular layers of soil texture.
Often, when planting azaleas and other woody plants, it is helpful to rinse the potting medium (which is mainly pine bark) from the roots before you plant.
Many soils in our area with a high clay content will wick moisture away from the pine bark-based growing mixes where the majority of the roots are and make it difficult for the plant to obtain the water it needs.
Another common mistake is not breaking up the root ball prior to putting the plant in the hole.
You may hear conflicting recommendations as to whether you need to do this, but if the roots are pot bound (having a dense external root mass) that will prevent good water movement into the internal portions of the root ball.
If it is not pot-bound, I still recommend it as I think the plants will get off to a much better start since they don’t have to break free of the root ball.
Digging a hole just big enough for the root ball has a similar effect. Both mistakes result in a stressed plant that is more susceptible to disease and that inexplicably dies during extreme environmental conditions.
Most of these plants I see and that are sent to the lab still have the root system in the original shape of the pot.
Finally, a good layer of mulch around the base of the plant will keep the roots moist and prevent weeds. Water the plant immediately after planting to settle the soil around the roots.
Don’t forget to give them water about once a week (depending on the soil type) in the absence of rain for the next six to eight weeks until they become established.
Keep in mind that a rotary sprinkler running 15-20 minutes may not be enough to wet all the roots. Hand water plants long enough for the water to soak down to the entire root ball.
On the other hand, you don’t have to water the plants every single day. I talk to numerous people who do that.
They wind up killing them with kindness. Think about it, roots underground will not dry out every day even during the middle of the hot summer.
REACH SID MULLIS, THE DIRECTOR OF THE UNIVERSITY OF GEORGIA EXTENSION SERVICE OFFICE FOR RICHMOND COUNTY, AT (706) 821-2349 OR SMULLIS@UGA.EDU.