How to Grow Horstmann Blue Atlas Cedar
by Ken Lain, the mountain gardener
The Horstmann Blue Atlas Cedar is a striking evergreen conifer with a naturally compact, pyramidal shape. Its silvery-blue needles and weeping branches add a touch of elegance to any landscape. This dwarf cultivar of the Blue Atlas Cedar is perfect for smaller yards where a full-size cedar would overwhelm the space. Exceptionally hardy and thrives in the mountain climate.
Botanical Name: Cedrus atlantica 'Horstmann'
Common Name: Horstmann Blue Atlas Cedar
Hardiness Zone: 6-9
Plant Type: Evergreen Conifer Tree
Size: 10' x 6' feet
Shape: Pyramidal, Weeping
Foliage Color: Silvery-blue
Landscape Uses: Specimen, Accent, Rock Gardens
Growth Rate: Slow
Plant Tolerance: Drought tolerant, adaptable
Standout Feature: Unique weeping form, silvery-blue foliage
Planting a Horstmann Blue Atlas Cedar
Choosing a site for this tree is crucial. While smaller than a full-size Blue Atlas Cedar, it still needs space to grow to its mature height of 10' feet tall and 6' feet wide. Full sun is best for vibrant color. As with all trees, never plant deeper than planted initially in the pot.
1. Dig a hole: 2-3 times the width of the container but the same depth.
2. Check drainage: Fill the hole with water. It should drain away within 12 hours. If not, amend the soil with Watters Premium Mulch to improve drainage.
3. Amend the soil: Blend 1 part Watters Premium Mulch with two parts native soil taken from the hole.
4. Score the root ball: Use a utility knife or pruners to score the sides and bottom of the root ball. This encourages outward root growth.
5. Plant the tree: Place the tree in the hole, ensuring the top of the root ball is level with the surrounding ground. Backfill with the soil-mulch mixture, packing firmly around the root ball.
6. Stake (if necessary): For extra support, particularly in windy locations, stake the tree using a sturdy stake and tree ties.
7. Water thoroughly: Build a well around the tree and water deeply with Watters "Root & Grow" liquid root stimulator.
Water: Water with Root & Grow every 2 weeks for the first 2 months. Then, water deeply once a month during the growing season, especially during hot, dry periods. Reduce watering in winter.
Soil and Sun:
This cedar prefers well-drained soil and thrives in full sun (6+ hours daily). It tolerates a variety of soil conditions, including alkaline and clay soils, but good drainage is essential.
Feed 3 times per year with the following:
· Spring: 7-4-4 All Purpose Plant Food + Soil Sulfur
· Summer: 7-4-4 All Purpose Plant Food
· Fall: 7-4-4 All Purpose Plant Food
Additional Tips:
· Mulch: Apply a 2-3 inch layer of mulch around the base of the tree, keeping it a few inches away from the trunk. This helps retain moisture and suppress weeds.
· Pruning: Minimal pruning is needed. If necessary, prune lightly in late winter to remove any dead or crossing branches.
· Pests and Diseases: Horstmann Blue Atlas Cedar is generally pest and disease resistant. However, watch for spider mites and bagworms.
Enjoy the unique beauty and elegance this stunning evergreen brings to your landscape!