How to Grow and Care for White Fir

White fir is a hardy evergreen conifer tree with distinctive blue-green needles and is often used as a Christmas tree. It is also grown in large public spaces and parks but its cultivars fit any size home landscape. White fir grows best in mountainous regions but is highly adaptable to many types of soil. The tree likes six hours of sunlight a day, slightly acidic, rocky soil, and can easily tolerate difficult northern weather conditions.

White Fir Care

Here are the main care requirements for growing white fir.

• Plant in full sun.
• Irrigate a young white fir tree frequently but it is drought-tolerant when it matures.
• Prefers rocky, gravelly soil that is well-draining and not soggy.
• Fertilize young white fir trees with evergreen food.

Light

White fir prefers to grow in full to partial sun. When the tree is young, it has the chance to burn its needles in the severe sun or severely dry weather. Keep younger trees in full sun either shaded or well irrigated.

Soil

Used to sandy, gravelly soil, the white fir thrives in soils it would find in its native mountainous regions. It is very adaptable, though, and will take to almost any conditions other than standing water. Providing it with slightly acidic, gravely soil is the perfect condition for white fir, but there won't be much of a fall-off in performance or health in other soils.

Water

The white fir is extremely drought-tolerant once it has established itself. Giving your tree supplemental irrigation is important to ensure healthy root growth during the first growing season or two. Watering the fir at about 10 gallons per inch of trunk diameter is a great guideline to follow that will get your tree going in a healthy direction.

Temperature and Humidity

This mountain terrain native can handle warmer temperatures and is very accustomed to the dry air of the western ranges of North America during the summer months. During the cold winter months, it can easily handle temperatures that plummet at high elevations down to −22 degrees Fahrenheit.

Fertilizer

There is no need to fertilize a mature white fir once it has been established. You may want to help your young tree along a bit by using a fertilizer specifically formulated for evergreens. Often these come in the form of slow-release spikes inserted at the base of the tree and will disintegrate over time. Once your tree reaches maturity, it will not need supplemental fertilizer.

Types of White Fir

The white fir has numerous cultivars to choose from to help you pick the best one for your landscape needs.

• Abies concolor 'Compacta': This dwarf cultivar is over a century old and grows in an oval form that reaches only 5 feet in 10 years.
• Abies concolor 'Blue Cloak': A weeping intermediate cultivar, this white fir grows to 8 feet in 10 years and has powder blue needles.
• Abies concolor 'Candicans Nana': The dwarf shrublike cultivar grows to only 4 feet tall with a spread of 6 to 8 feet wide.
• Abies concolor 'Wintergold': This tall upright tree is a unique and seasonally variable gold-colored dwarf cultivar that begins chartreuse in the spring, turning bright green, and then finally to gold in the winter.
• Abies concolor 'Piggelmee': This slow-growing miniature white fir cultivar has pale blue foliage and grows as a dense, compact mound low to the ground up to 12 inches tall.

Pruning

Pruning a coniferous tree like a white fir is rarely done because it grows into its pyramidal shape without much fuss. However, prune away dead, broken, or diseased branches when you see them. In the winter, remove branches that are touching the ground to improve the air circulation around the tree. Otherwise, you might want to leave a white fir undisturbed.

Propagating White Fir

It's generally recommended to plant a white fir you have purchased from a nursery rather than try to propagate by a cutting or seeds. If you are patient and up for the challenge, the easier way to propagate a white fir is with a cutting. In the late spring, cut a softwood cutting, or in late fall when the tree is dormant, cut a more mature hardwood cutting.

1. Take a 6- to 8-inch cutting with a sterilized cutting tool.
2. Remove all needles and dip one end in rooting hormone.
3. Put 3 inches of the end with the rooting hormone into a pot filled with a moistened rooting medium, such as a mix of perlite, sand, or peat moss.
4. Put a clear plastic zip bag over the pot. Add a couple of small holes so the plant can breathe.
5. Put the pot in a warm space with indirect sunlight.
6. Mist or water the stems frequently so they do not dry out but do not make the soil soggy, either.
7. Plant the seedling in regular potting soil when it reaches around an inch tall. It may take months for the hardwood cutting to grow but softwood may root in a few weeks.
8. Keep the plant in a pot for about a year before placing it outdoors.

How to Grow White Fir From Seed

Growing a white fir from seed is a long process with spotty results. Harvest seeds when the tree's cones shed seeds in late September or early October. Seeds germinate in the spring.

1. Soak the seeds in water for 24 hours.
2. Put seeds in moistened soil or peat/perlite.
3. Stratify seeds by placing them in the refrigerator for 60 days. This step is optional.
4. Directly seed multiples (10 to 15 seeds at a time) in the ground or place them in pots placed in a cold frame as soon as they are harvested and if you are not stratifying them.

Common Pests & Plant Diseases

Pests include balsam twig aphids, bagworms, scale, fir engraver and bark beetles, and spider mites (in hot weather). Apply insecticidal soaps or oils to minimize the issues.

Fungal issues can include twig blight, canker, and root rot, especially Armillaria root rot. Rust is another problem afflicting white fir across the country. To avoid fungal issues, keep the tree healthy and free of broken branches with open wounds. Also keep the tree watered, but avoid overwatering, especially near the trunk, in very dry weather.

Common Problems With White Fir

The white fir is usually a strong and healthy tree that does not need much intervention. However, stay on the lookout for any of these issues.

Weak Limbs

Watch for broken, dangling limbs that need to be removed. Strong winds may damage taller trees.

Scarred Trunk

White fir has thin bark. Be careful when mowing around the tree. Accidentally banging into the tree can cause scarring or wounds.

Dieback

If your otherwise healthy white fir appears to be experiencing dieback, contact a licensed arborist to diagnose the problem. It is likely a type of a type of rust, root rot, or blight.