Arborvitae are a popular and attractive evergreen tree that are commonly used in landscaping. Here's how to plant, grow, and prune arborvitae in your home garden!
About Arborvitae
The elegant American arborvitae (Thuja occidentalis) is a hardy, native evergreen with a narrow pyramid shape. It's a natural choice for privacy hedges and windbreaks when planted in rows. Dwarf and miniature cultivars make great accent plants or foundation plantings, too. Arborvitae will add color and texture to your landscape. Plus, easy care requirements make this a rewarding plant to grow.
Planting
When to Plant Arborvitae
- Plant in early spring when the soil can be worked or in the fall before the ground freezes.
Choosing and Preparing a Planting Site
- Choose a location in full sun or partial shade.
- Amend the soil by digging in about 2 inches of compost or aged manure.
How to Plant Arborvitae
- Dig the planting hole 2 to 3 times as wide and as deep as the root ball.
- Loosen some of the roots in the root ball.
- Plant the arborvitae in the hole so that the top edge of the root ball is level with the top of the hole.
- Back-fill with soil around the root ball, tamping down with your hands.
- Soak the soil in the hole when you have filled it ½ full.
- Finish filling to the top edge of the root ball.
- Water deeply.
- Add a 2 inch layer of aged shredded wood mulch or pine straw around the arborvitae to conserve moisture. Avoid placing mulch directly against the stem.
Care
How to Grow Arborvitae
- Keep the soil consistently moist the first growing season. Don’t let the soil dry out but be careful not to over-water.
- Established arborvitae will require extra water only during prolonged periods of drought.
- Use stakes for support as newly planted arborvitaes are vulnerable to wind.
- Fertilize the arborvitae in the spring with a slow-release high-nitrogen shrub/tree fertilizer.
How to Prune Arborvitae
- Arborvitae do not require a lot of pruning.
- Plants that are used in formal hedges and foundation plantings can be trimmed with hedge shears to shape and to spur new growth.
- Prune in early spring before new growth emerges.
- Trim from the bottom up.
- Shorten branches that are expanding beyond the desired length.
- Prune damaged branches anytime.
How to Propagate Arborvitae
- Take stem cuttings in late summer or fall.
- Cut 4 to 5 inch cuttings from current year’s branch growth.
- Remove the leaves on the bottom half of the cutting.
- Fill a small pot with organic soil mix or a mixture of sand and peat moss.
- Stick the cutting into rooting hormone and then into the pot.
- Water and cover the pot with a plastic dome or clear plastic wrap.
- Place the pot in a location with filtered light.
- Water if soil gets dry.
- It will take 6 to 8 weeks for the roots to form.
- Remove the plastic covering.
- Transplant into a bigger pot with soil.
- Plant outdoors the following spring.
Pests/Diseases
Insect pests
- Spider mites
- Bagworms (occasionally)
- Arborvitae leafminer
Animal pests
Diseases
- Needle blight
- Botrytis twig blight
Recommended Varieties
The American arborvitae is a tall, dense, broad-pyramidal evergreen. This native tree can reach heights of 40' to 60'. Choose plants with strong central stem to avoid damage from wind, snow or ice.
- ‘Brandon’ is a conical evergreen that can reach a height of 15’ and a width of 8’. This cultivar is mildly fragrant and has scale-like foliage. It will tolerate a wide range of soil types as long as periodic deep watering is provided.
- ‘Emerald Green’ is a favorite for hedges. It grows to15 feet tall and 4 feet wide forming a tall column of brilliant green foliage.
- ‘Art Boe’ also called North Pole arborvitae is a narrow upright shrub. It can grow for years in a container or if planted in the ground it grows to 15 feet.
- ‘Hetz Midget’ is a hardy dwarf that reaches 3 to 4 feet tall. Its naturally round form makes it ideal for foundation plantings.
- ‘Tom Thumb’ is a miniature and grows only 12 to 15 inches tall. It is a dense multi-stemmed shrub with a rounded form, perfect for containers or rock gardens.
Wit and Wisdom
- The name arborvitae is the Latin form of the French l'arbre de vie, which means, "tree of life."
- The genus name, Thuja, is from a Greek word for perfume.
- Arborvitae was the first North American tree to be introduced to Europe.
- Other names for arborvitae include northern white-cedar, eastern white-cedar, and swamp-cedar.
- The oldest living arborvitae is over 1,000 years old.
- Native Americans made baskets from the roots and used the leaves in tea.
- The wood is used for log cabins, fence posts, shingles, paneling, canoes, and wood crafting.
