As a general rule, anytime a tree or shrub dies within the first year of planting, there is usually a root issue involved. Spring planted trees and shrubs are generally more stressed from summer heat, since their roots are still underdeveloped during the first year. This results in excessive wilting, which causes well-intentioned gardeners to literally water their plants to death.
Fall and winter planted trees and shrubs can more quickly become established in their new environment while they are dormant—giving them far more resilience during their first summer. Even with proper timing and planting technique, woody plants may still take a few years to fully establish and recover from transplant stresses.
Spring plantings are also more likely to suffer from chronic transplant shock. Under stressful conditions, plants are unable to recover, continue to decline, and eventually die. The most common reasons for transplant shock and root-stress are planting too deep, poor drainage, backfilling with composted soil amendments, damaging the stem/root ball connection during planting, or excessive watering. It’s possible that a combination of these issues may be involved, especially with the amount and frequency of rain we’ve had the past few years in North Georgia.
From my experience, it seems that many problems related to transplant shock are the result of old habits and misinformation. Many folks that are new to North Georgia don’t know what to do with our clay soil. If you are human “transplant” from Florida, South Georgia, or the West coast, how you plant trees and shrubs in those regions is very different than here. Clay soils function differently than sandy/loamy soils found elsewhere. Clay has the ability to hold water for several days, drains very slowly, and has less oxygen available to roots—especially if compacted.
These unique traits of clay soil are the reason why we don’t recommend backfilling with composted soil amendments, which can act like a sponge in a bowl—staying either too wet or too dry and disrupting normal drainage. Water tends to accumulate at the bottom of the bowl and results in root rot. Also, it’s best to allow trees and shrubs to breathe a few days between watering. One inch of rain or irrigation can take several days to fully drain from clay soil. Roots can literally suffocate from watering too frequently. Planting roots too deep will make problems worse in clay soil due to poor drainage. The root flare at the base of the stem should always be visible or slightly above grade in a clay soil.
Unfortunately, root stresses do not have a good remedy. Mulch is an important part of planting and caring for landscape trees and shrubs. Maintain a 2” to 3” inch mulch layer of pine straw or wood chips to conserve soil moisture. Dead branches that result from transplant shock should be pruned out as needed. Note that adding fertilizer can actually stress new plants further by forcing new growth that the roots are not yet able to sustain.
In most situations it is best to replace the plant once you experience more than fifty percent dieback. Also, realize that even if a plant “survives” transplant shock, it will continue to be stunted/stressed for several years and may never reach its fullest potential. If you do decide to replace the plant, wait until fall or early winter, which is the best time to plant.
For more information view UGA Extension Bulletin 932, “Soil Preparation and Planting Procedures for Ornamental Plants in the Landscape” available your County Extension office or on our website at extension.uga.edu/publications.
Paul Pugliese is the Extension Coordinator and Agricultural & Natural Resources Agent for Bartow County Cooperative Extension, a partnership of The University of Georgia, The U.S. Department of Agriculture, and Bartow County. For more information and free farm, lawn, or garden publications, call (770) 387-5142 or visit our local website at extension.uga.edu/bartow.