Childs said that the fall it is best time to transplant conifers. Once you have your trees ready for planting, take the burlap, wire, or bucket off of the plant and examine the roots. Plant the tree only up to the root flare. The root flare is what it sounds like, where the roots begin to flare out. Childs said that if you plant the tree above the flare, it will likely kill the tree. He added that most people expect to be able to just take the burlap or bucket off the root ball and just drop it in the ground. “Sometimes the flare ends up in the middle of that root ball,” said Childs. “Take off as much wrapping as possible and really examine what you have.”
Make sure your conifers receive adequate water following planting, especially when there is a drought.
Childs said that “unless its incredibly poor soil, you shouldn’t have to use peat, compost, or manure to fertilize.” Childs recommended that only in the worst soil conditions should a fertilizer such as a 10-10-10 mix be used.
What insects are conifers susceptible to, and what do I do about them?
Conifers don’t tend to be especially attractive to insect infestations with a few notable exceptions. Mugo, or dwarf mountain pines, are susceptible to caterpillar infestations. Mugo pines are often used as ornamentals around rock gardens as they are low-lying. Some conifers are susceptible to pine needle scale and spider mites, and hemlocks may attract wooly adelgid, which was introduced to the northeastern US in the 1950’s.
Wooly adelgid are fluid sucking insects similar to aphids. “It has weakened a lot of trees and can kill them,” said Childs. Do not fertilize with nitrogen-containing products if you have wooly adelgid, as they thrive on nitrogen.
There are many pesticides approved for homeowner use, some of which are earth-friendly such as horticultural oils and insecticide soaps. However, you may want to call in a professional if the problem gets out of hand. You also may need to take out any diseased/infested trees so that any others around them have a better chance for survival.
What about pruning?
Due to the fact that the conifers you are transplanting have been stressed by the process, you don’t want to do any heavy pruning initially said Childs. “You shouldn’t prune at planting unless you have broken or damaged limbs,” said Childs. “The foliage and roots ‘talk’ to each other via hormones.” He said the communication process that goes between roots and foliage on lets the tree know it needs more water or certain types of nourishment.