If you’re planning a hedge or a new foundation planting, a common question is how fast do arborvitae grow. Understanding their growth rate clearly helps you plan your garden space and manage your expectations for privacy and landscape design.
These popular evergreens are known for their reliability, but their speed isn’t the same for every type. We’ll break down the factors that influence their pace and give you clear numbers for the most common varieties.
How Fast Do Arborvitae Grow
On average, most common arborvitae varieties grow about 1 to 2 feet per year once they are established in your garden. However, this is a general range. The actual speed depends heavily on the specific cultivar, your local conditions, and the care you provide.
In their first few years after planting, arborvitae focus energy on developing a strong root system. You might not see much upward growth during this time. This establishment phase is crucial for their long-term health and drought tolerance. After that, they typically hit their stride and put on more consistent annual growth.
Growth Rates of Popular Arborvitae Varieties
Choosing the right type is the biggest factor in determining growth speed. Here’s a clear look at some favorites:
- Emerald Green (Thuja occidentalis ‘Smaragd’): This is a very popular choice for narrow hedges. It grows at a moderate pace of about 12 to 18 inches per year, eventually reaching 12-15 feet tall.
- Green Giant (Thuja standishii x plicata ‘Green Giant’): As the name suggests, this is a fast-grower. It can add 3 to 5 feet per year under ideal conditions, quickly forming a tall, dense screen.
- American Arborvitae (Thuja occidentalis): The standard species grows around 1 to 2 feet yearly, maturing into a large, pyramidal tree over decades.
- Techny (Thuja occidentalis ‘Techny’): Also known as ‘Mission’, this cultivar is valued for its cold hardiness and full shape. It grows steadily at about 1 foot per year.
- Degroot’s Spire (Thuja occidentalis ‘Degroot’s Spire’): This unique, twisted variety is a slow grower. Expect only 4 to 6 inches of growth per year, making it excellent for small spaces.
Key Factors That Affect Arborvitae Growth Speed
Why does one person’s arborvitae thrive while another’s struggles? Several environmental and care factors play a huge role.
Sunlight Exposure
Arborvitae grow fastest and densest in full sun, meaning at least 6 hours of direct light daily. They can tolerate partial shade, but growth will be significantly slower, and the foliage may become thin and sparse.
Soil Quality and Drainage
This is critical. Arborvitae prefer moist, well-drained soil that is rich in organic matter. They struggle in heavy, soggy clay or in very dry, sandy soil. Poor drainage is a leading cause of root rot and stunted growth.
Watering Practices
Consistent moisture is key, especially for new plants. They need deep watering weekly during dry spells. Established trees are more drought-tolerant, but prolonged dryness will slow growth and cause browning.
Climate and Hardiness Zone
Most arborvitae thrive in USDA zones 3-7, though some varieties extend that range. Extreme heat in southern zones can stress them, slowing growth. Winter burn in very cold, windy areas can also set them back.
Nutrition and Fertilization
While not heavy feeders, arborvitae benefit from an annual application of a balanced, slow-release fertilizer in early spring. Too much fertilizer, especially high-nitrogen formulas, can cause weak, overly fast growth that’s susceptible to damage.
How to Maximize Your Arborvitae’s Growth Rate
To help your arborvitae reach its full potential, follow these practical steps from planting onward.
- Plant Correctly: Dig a hole twice as wide as the root ball but no deeper. Planting too deep is a common mistake that suffocates roots. The top of the root ball should be level with the soil surface.
- Amend the Soil: Mix compost or aged manure with the native soil you use to backfill the hole. This improves drainage and provides nutrients right where the young roots need it.
- Water Deeply and Regularly: For the first two years, don’t rely on rainfall alone. Provide 1 inch of water per week, soaking the soil deeply to encourage roots to grow downward.
- Apply Mulch: Spread a 2-3 inch layer of mulch (like wood chips) around the base, keeping it a few inches away from the trunk. Mulch conserves moisture, regulates soil temperature, and suppresses weeds.
- Fertilize Annually: In early spring, apply a granular, slow-release fertilizer formulated for evergreens. Follow the package instructions to avoid over-application.
- Protect from Damage: Shield young trees from winter wind and salt spray with burlap screens if needed. Guard the base from lawn mower and string trimmer damage, which can wound the bark.
Common Problems That Slow Down Growth
Even with good care, issues can arise. Watch for these signs that your arborvitae’s growth is being hindered.
- Pest Infestations: Bagworms, spider mites, and deer browsing can remove foliage and stress the plant. Inspect your trees regularly, especially the inner branches.
- Diseases: Fungal diseases like tip blight or root rot cause browning and dieback. These often stem from poor air circulation or overly wet conditions.
- Poor Planting Site: Competition from large tree roots, soil compaction, or insufficient space for the mature size will all limit growth. Always check the mature width before planting.
- Nutrient Deficiencies: Yellowing foliage (chlorosis) can indicate a lack of essential nutrients, often due to poor soil pH. Arborvitae prefer slightly acidic to neutral soil.
Pruning and Shaping Your Arborvitae
Pruning mainly maintains shape and density; it doesn’t significantly speed up height growth. The best time to prune is in early spring before new growth starts. You can also do a light trim in mid-summer if needed.
Always use sharp, clean tools. Avoid cutting back into old, brown wood, as most varieties will not produce new growth from these areas. Instead, trim the green, leafy shoots to encourage bushier growth on the outside.
Setting Realistic Expectations for Your Landscape
Patience is essential in gardening. A ‘Green Giant’ might give you a quick screen in 3-5 years, while an ‘Emerald Green’ hedge will take longer to fill in. Slow-growing varieties are perfect where you don’t want constant pruning.
Consider your long-term goal. For a permanent 20-foot tall screen, a fast grower is great. For a low-maintenance foundation plant, a slower cultivar is often a better, more manageable fit. Planning with the mature size in mind saves you from future headaches.
FAQ: Your Arborvitae Growth Questions Answered
How fast do arborvitae grow per year?
Most grow 1-2 feet yearly, but fast types like ‘Green Giant’ can grow 3+ feet, and slow types like ‘Degroot’s Spire’ grow under 6 inches.
What is the fastest growing arborvitae for privacy?
The ‘Green Giant’ is the champion for quick privacy screens due to its rapid 3-5 foot annual growth rate and dense foliage.
Why is my arborvitae growing so slow?
Check for insufficient sun, poor soil drainage, compacted roots, lack of water, or pest/disease issues. The first year after planting is always the slowest.
How can I make my arborvitae grow thicker?
Ensure it gets full sun and adequate water. Lightly pruning the tips of new growth in spring stimulates branching, leading to a denser habit.
Do arborvitae stop growing after a certain height?
They will eventually reach their genetic mature height and slow way down, but this can take decades for many large varieties.
Understanding how fast arborvitae grow clearly involves looking at the whole picture. By selecting the right variety for your goal and providing consistent care with good sun, soil, and water, you’ll set your plants up for success. Remember, a healthy tree is a fast-growing tree, so focus on creating the right conditions from the start. With a little patience, you’ll be rewarded with beautiful, lush greenery that enhances your landscape for years to come.