Transplant shock is a term that refers to the stresses a recently transplanted shrub or tree can experience. It is a biological process that occurs when the plant being installed has not established a root system extensive enough to keep up with the needs of the plant.
Often, a newly transplanted tree or shrub won’t have an extensive root system. As a result, they can suffer stress because the trimmed/disturbed roots can’t absorb enough water to supply to the plant. If a plant is experiencing transplant shock, it may be more susceptible to injuries from other outside causes, such as disease, insects or weather. With proper care and extra watering until the roots are more established, a plant can overcome transplant shock. If proper care isn’t provided, the plant may decline or die.
A general rule for trees is to expect one year of transplant shock for every inch in caliper (diameter), or the truck. The larger the tree at time of installation, the longer it will have to work to overcome transplant shock. The type of tree can also affect likelihood and duration of transplant shock.
Leaf Scorch: The First Sign of Transplant Stress
One of the most commonly seen signs of transplant stress is leaf scorch. This usually starts as a bronzing or yellowing of the tissue present between or along the leaves margins in deciduous plants (a deciduous plant is one that loses its leaves during colder months of the year). Later, the discolored leaf dries out and turns brown in color.
Some of the other signs and symptoms of transplant shock include:
- Wilting leaves
- Yellowing leaves
- Leaf curling or rolling
For evergreen trees with needles, the first sign of water stress is an overall grey-green coloration to the foliage. As water stress continues, the needles may begin to turn a light color on the end. If the stress is not alleviated, then the leaf will die, which can be followed by twig and limb dieback.
Causes of Transplant Stress
There are several reasons that plants may become stressed. Some of the most common include:
- A poor or injured root system
- Improper planting techniques
- The roots are unable to spread if the plant is put in a container
- The plant is not watered properly
- A plant that isn’t right for the region/location
Effects of Transplant Stress
When transplant stress occurs, it can result in the reduction of the plant’s growth. This is seen in how much the new sprigs grow. If a plant is not growing properly, it often has significantly shortened internodes, which can result in shorter branch tips compared to those of a plant that is not suffering from stress. Also, new needles or leaves of a plant under stress are going to be smaller than what is considered normal. It isn’t unusual for a transplanted plant to have extremely reduced growth the initial year after being planted; however, symptoms of this problem may be seen for two years or more.
Overcoming Transplant Shock
Follow a watering schedule provided by your landscape professional or local educational institution. Watering more frequently until the roots are established will help overcome much of the symptoms. There is no way of totally preventing something that is a biological process, but proper care, proper planting, and attention to plant health will increase chances of plant success.
If you have a plant that dies due to transplant stress, then you should try to figure out what caused this. If you are unsure, work with the professionals before trying to transplant another plant. This will give you a better chance of success the second time around.
