How to Grow and Care for Black Hills Spruce

The Black Hills spruce tree is a cultivar of white spruce that grows high in the Black Hills of South Dakota and is known for its aromatic deep green to blue-green needles and dense, narrow form in the landscape. The Black Hills spruce grows best in dry, non-humid conditions with cold winters and cool summers, but the tree requires full sunlight and acidic soil. Be aware that this tree will only do well in USDA hardiness zones 3-6.

Black Hills Spruce Care

Here are the main care requirements for growing a Black Hills spruce tree:

• Site this tree in full sun.
• Add compost to the soil when planting the tree.
• Plant in well-draining soil that is a bit more on the acidic side.
• Make sure the tree can breathe well since it prefers dry, cool air but moist soil.
  
• Requires little pruning except for low and drooping branches if desired.

Light

The Black Hills spruce will grow in partial shade for those with less ideal light conditions. It does prefer full sun, though, and you will see slower growth if you plant your tree in anything less than six to eight hours of sun.

Soil

For those looking for a particularly adaptable tree for soil conditions, the Black Hills spruce might be the tree for you. It can do well in well-draining clay, loam, and sand. While it can handle some alkalinity, your tree will favor slightly acidic soil. You can always test this using a simple pH test and amend the soil as needed.

Water

Once your tree is established, it won’t need much supplemental watering, but until then, you will need to water it weekly during periods without heavy rains. Continue this for the first two years, and your tree will be one step closer to establishing a well-watered, healthy root system.

Temperature and Humidity

This particular cultivar of white spruce lives in the Black Hills of South Dakota at elevations higher than 6,000 feet. Because of this, it has adapted to dry conditions, cold winters, and cool summers. When placing it at lower elevations, be sure to plant it in a location that leaves ample room for airflow to allow the wind to dry moisture from its branches.

Fertilizer

There is no real need to give this tree supplemental fertilizer. When refilling the hole you dug to plant your spruce, add good organic compost to the back-fill. If you should notice any signs that your tree is suffering, test the soil and check if deficiencies can be corrected by adding nutrients as needed.

Types of Black Hills Spruce

While there are only three varieties of Picea glauca, there are many cultivars. Black Hills spruce was formerly designated as var. densata. It is now considered the cultivated variety (or cultivar) 'Densata' since it is biologically too similar to wild white spruce populations to constitute a unique variety.

Because of this, you will only find one type of Black Hills spruce commercially available.

Pruning

Prune dead or broken branches at any time. You also can raise the canopy by removing drooping, lower branches at the trunk. Do any optional pruning in late winter or early spring. Otherwise, the tree will not need regular pruning.

How to Propagate Black Hills Spruce

Propagate Black Hills spruce trees by seed or cutting, just as you would any white spruce tree. Take these steps if you choose to do cuttings in the late summer or early fall:

1. Using a sterilized cutting tool, clip off a healthy 6- to 8-inch shoot.
2. Angle the base of the cutting with another cut using a sterilized tool.
3. Remove all the needles from the lower portion of the cutting, leaving the top 1/3 section of needles in place.
4. Dip the angled end of the cutting in rooting hormone, though this is an optional step.
5. Plant the cutting directly into moist soil in a sunny spot outdoors and keep moist.
   

How to Grow Black Hills Spruce From Seed

Growing a spruce tree from seed takes patience because you need to let the roots mature a bit before planting outdoors. However, there will be an abundance of seeds in the cones produced by this spruce tree so you can plant a stand of them if you desire. Black Hills spruce tree's cones are small, about the size of a large thumb.

1. Watch for fallen cones in the fall and let them dry thoroughly. They will open on their own and you can collect the seeds.
2. Place the seeds in a plastic bag and put them in the refrigerator for three weeks.
3. Remove the seeds and soak them in water for 24 hours. Use seeds that sink and discard seeds that float to the top because they are not viable.
4. Plant seeds in a small pot filled with rich soil.
5. Cover the seeds and keep the soil moist, but never soaked.
6. Place pots in a protected area outdoors in the late spring.
7. Seeds will typically germinate in three weeks.
8. Keep a seedling in a pot for at least a season to let the root system grow and then you can plant it in the ground.

Common Pests & Plant Diseases

Mites, aphids, and bagworms are the most common pests with the Black Hills spruce, though none should be able to do enough damage to a healthy tree to kill it. Bagworms are the most obvious pest and can be unsightly. Remove those within reach by hand and treat the tree with Bacillus thuringiensis.

The only diseases that may cause you the rare issue are various rusts. One occurrence of rust will not likely be of concern. A common sign is the yellowing and dropping of infected needles.

Common Problems with Black Hills Spruce

The Black Hills spruce does not have many issues unless it's placed in an unsuitable environment. Note that the tree does not like urban or coastal environments due to humidity, overcast, or wet conditions.

From: thespruce