ASK THE HORT AGENT
Question When is the best time to transplant trees and/or shrubs?
Answer Fall is the best time of year to transplant trees and shrubs. Itís cooler outside, and working outside beats the heck out of watching presidential campaigns. Mosquitoes are the only downside.
Now is the best time to transplant woody plants because of the ď2 for 1 deal.Ē When you dig up a shrub, you move the stem, but most of the roots are still in the ground. Plants like to live with a balanced ratio of roots to shoots (leaves). When we transplant a plant and cut off the roots, we offset that ratio. The plant now has more shoots than roots. So, we want to give the plant every opportunity to get closer to its original root to shoot ratio.
In the fall, the days are shorter than the nights (less sunlight). The air and ground temperature is cool (not hot and not cold). This combination of day length and temperature decreases shoot growth and increases root growth.
During the winter, growth of roots and shoots nearly shuts down. As spring approaches, the ground warms and daylight is still limited. Roots begin to grow again before the leaves. When spring finally gets here, the leaves begin to pop out again. Therefore, if you transplant your shrubs in the fall, they have two seasons (fall and late winter) to grow roots before the leaves pop out in the spring Ė the ď2 for 1 deal.Ē
Since leaves make energy for the plant, most people think leaves are the most important part of a plant. While leaves are the energy makers (actually converters), they are also the water losers. Roots are the water-getters. If a plant is losing more water than it is taking up, it dies. Think of our government. If we are spending more money than we are taking in, then we enter a deficit (which is not good by the way). A water deficit for your shrubs means death.
Root pruning is another method to insure survival after transplanting. Like shoot pruning, this method encourages growth. Root pruning is basically cutting the roots with a shovel without digging up the plant. The only drawback is timing. Roots need to be pruned at least 6 months before the plant is transplanted. Trees and/or shrubs can be root pruned now for transplanting this spring. Not even 700 billion dollars will make a plant grow a root faster.
For more info on transplanting, visit http://hgic.clemson.edu/factsheets/hgic1055.htm
If you donít have internet access, then call the Extension Office at 893-7533 or email me at firstname.lastname@example.org Iím Gary Pierce and I approved this message.
Gary L. Pierce
Horticulture Extension Agent