Spectacular Douglas-firs in winter
Douglas-fir (Pseudotsuga Menziesii) is a perennial tree that grows in gardening zones 4 to 6 to a height of 40 to 80 feet. The tree can reach 200 feet at 20 to 40 years old, making it a spectacular specimen for landscaping. Douglas-fir trees are also grown in groups or "stands," making excellent windbreaks and providing cover for wildlife. Both the seeds and needles are food for birds and animals. Douglas-fir trees are readily available for home landscaping and commercial use from garden centers and wholesale suppliers. Commercially, Douglas-fir trees are cultivated for their wood, used in the construction and paper industries, as well as for fire wood. Because of their pleasing shape and long needle retention, Douglas-firs make popular Christmas-tree choices.
Instructions
Planting and Cultivating the Douglas-Fir Tree
1. Douglas-fir trees at night
Purchase healthy plants. Seedlings and bare-root plants can be purchased, but the best home results are obtained by buying more established plants. Specimens in at least 2-gallon or larger containers are more likely to survive the first year and eventually turn into a dramatic landscape accent.
2. Pick a location protected from high winds in full sun to part shade. Douglas-fir is not as drought tolerant as some other conifers, so do not locate in blazing sun at high elevations. Drainage should be excellent to prevent root rot, but light moisture retention of the soil is also important. Spring is the best time to plant, although fall planting is possible.
3. Dig the hole. The planting technique is similar to any long-lived perennial tree. Loosen the soil with a garden fork and remove it from the hole with a space or shovel. Dig a hole twice the depth of the root ball and mix a good amount of compost and peat moss into the bottom of the hole. Fill the hole 1/2 full with water and allow to drain before positioning the tree. Add in soil mixed with compost and peat moss around the sides, watering between layers of added soil. Finally, tamp down the top soil, then use the extra dirt to create a wide ring or moat around the tree to hold in moisture.
4. Spray animal repellant to protect your trees
Spray plants thoroughly with animal repellent. Repellents should be sprayed on plants at the time of planting and work by using substances such as predator urine, dried blood and egg solids to keep away deer, elk, rabbits, mice, beaver and other animals that can harm the trees. Re-spray at intervals, following manufacturer's directions to keep animals from snacking on the young trees.
5. Mulch
Apply mulch to a depth of 4 inches. Bark landscape mulch is a food choice to conserve moisture and protect the soil from drying out. The mulch also prevents weeds from taking hold and from competing with the tree for nutrients. The Douglas-fir trees also stand out and look attractive with the dark mulch background.
6. Water often
Water frequently. Water Douglas-firs every day for three days after planting and weekly thereafter until established. Young trees and more mature trees planted at higher altitudes or anywhere that summers are hot and winters are cold will need regular watering several times a month during the summer and during any part of the growing season that rain is scarce.
On-Going Care of Douglas-Fir Trees
7. Apply fertilizer once a year. Trees planted in the fall should be fertilized the following spring. Apply fertilizer to spring-planted trees six to eight weeks after planting. Use a balanced, slow-release fertilizer such as 10-10-10 and follow package directions, applying in a light band around the perimeter of the planting hole under the branches.
8. Lightly prune to shape
Prune to establish an optimum conical shape. Until the trunk is 10 inches in circumference, light pruning to obtain a good shape is permissible. After the trunk size is reached, the tree should be left to grow on its own, except to remove dead or diseased branches.
9. Kill pests with natural or chemical controls. Several pests can damage Douglas-fir trees. The Douglas-fir Tussock Moth defoliates the tree from the top down, and the Western Spruce Bud worm is another highly destructive pest and defoliator. When needle drop occurs, the trees should be examined to determine which pest is at work. Bt, Bacillus thuringiensis is a natural biological control that can be tried for spruce bud worm infestation before resorting to chemical sprays. Check with your garden supply store to see which chemical controls are legally allowed in your area.
