How Tall Do Arborvitae Grow

When planning your garden, a common question is how tall do arborvitae grow. The answer is not simple, as arborvitae varieties have vastly different mature heights, making selection important for your landscape plan. Choosing the right one depends on your goal, whether it’s a privacy screen, a foundation planting, or a standalone specimen.

This guide will walk you through the expected heights of popular arborvitae types. You will learn about dwarf, medium, and towering varieties. We’ll also cover the factors that influence their growth and how to manage it.

The potential height of an arborvitae is primarily determined by its cultivar, or cultivated variety. On the extreme ends, some dwarf types stay under 3 feet tall, while certain giant species can soar over 60 feet. For most residential landscapes, popular varieties fall into a range of 10 to 30 feet at maturity.

Mature height is typically measured after 10 to 20 years of growth under ideal conditions. It’s crucial to check the specific cultivar’s tag or description. Assuming all arborvitae grow to the same size is a common mistake that leads to overcrowding and excessive pruning.

Key Factors Influencing Arborvitae Height

While genetics set the maximum potential, several environmental factors determine if your tree reaches that potential. Understanding these helps you set realistic expectations and provide the best care.

Sunlight Exposure

Arborvitae thrive in full sun, meaning at least six hours of direct sunlight daily. In full sun, they grow denser and closer to their genetic height potential. In heavy shade, growth slows significantly, and plants become thin and leggy as they stretch for light.

Soil Quality and Drainage

These trees prefer moist, well-drained soil rich in organic matter. Poor, compacted, or constantly soggy soil stunts root development, which directly limits upward growth. A soil test can reveal nutrient deficiencies that might slow growth.

Climate and Hardiness Zone

Each cultivar is rated for specific USDA hardiness zones. A tree planted outside its recommended zone may struggle with winter damage or summer heat stress, hindering its growth and overall health.

Watering and Nutrition

Consistent moisture, especially for young trees, is critical for establishing a strong root system that supports vertical growth. A balanced, slow-release fertilizer applied in early spring can promote healthy growth, but over-fertilization can cause weak, rapid growth that’s susceptible to damage.

Dwarf Arborvitae Varieties (Under 6 Feet Tall)

Dwarf arborvitae are perfect for small spaces, rock gardens, or low hedges. They provide evergreen structure without overwhelming the landscape. Their slow growth means they require minimal pruning to maintain their size and shape.

Danica: A perfectly globe-shaped cultivar that rarely exceeds 2 feet in height and width. It’s excellent for borders or container planting.
Little Giant: As the name suggests, it’s a small, rounded form of the popular ‘Green Giant’, typically staying around 4 to 6 feet tall and wide.
Hetz Midget: One of the smallest, forming a dense dark green ball that grows only about 3 to 4 inches per year, maxing out near 3 to 4 feet.
Mr. Bowling Ball: A unique, fine-textured variety with a natural, compact spherical form, reaching about 2 to 3 feet tall.

Medium-Height Arborvitae Varieties (6 To 20 Feet Tall)

This is the most versatile group for home landscapes. These varieties are ideal for privacy screens, windbreaks, and accent plantings. They offer significant height without becoming unmanageable.

Emerald Green (Smaragd): Perhaps the most popular, it forms a narrow, bright green pyramid. It slowly reaches 12 to 15 feet tall but stays only 3 to 4 feet wide, perfect for tight spaces.
Techny (Mission): Known for excellent winter hardiness and retaining its dark green color. It grows to a broad pyramid shape, 10 to 15 feet tall and 6 to 8 feet wide.
Degroot’s Spire: An extreamly narrow columnar form, growing to 10 feet tall but only about 2 feet wide. It’s ideal for creating vertical accents.
North Pole: A cold-hardy, columnar variety that grows to 10 to 15 feet tall with a spread of 3 to 5 feet. It’s a good alternative to ‘Emerald Green’ in colder zones.

Tall And Giant Arborvitae Varieties (20+ Feet Tall)

These are the giants of the arborvitae world, best suited for large properties, commercial landscapes, or as stately specimen trees. They grow rapidly and can quickly create a tall, dense barrier.

Green Giant: The champion of fast growth, often adding 3 feet per year. It matures at a massive 40 to 60 feet tall and 12 to 18 feet wide. It’s resistant to deer and many common diseases.
American Arborvitae (Thuja occidentalis): The straight species can reach 40 to 60 feet in the wild. Cultivars like ‘Nigra’ are more common in landscapes, growing to 20 to 30 feet.
Oriental Arborvitae (Platycladus orientalis): Often has a more open, irregular form. Some cultivars, like ‘Aurea Nana’, are dwarf, but the species can reach 18 to 25 feet.
Korean Arborvitae (Thuja koraiensis): Less common, it typically grows as a spreading shrub but can reach 15 to 30 feet in ideal conditions, with beautiful silver-white underside foliage.

Growth Rate And Time To Maturity

Growth rate varies dramatically. Dwarf types may grow less than 3 inches per year, while ‘Green Giant’ can grow over 3 feet annually. Most medium-sized landscape varieties grow at a moderate rate of 6 to 12 inches per year.

Time to maturity is relative. A tree may reach its near-maximum height in 15-20 years but continue to fill out and gain girth for decades after. When planting for privacy, consider the growth rate to know how long you’ll wait for your screen to fill in.

Pruning And Height Management

You can control the height of your arborvitae to some extent through pruning, but it’s best to choose a variety that naturally fits your space. Pruning is for maintenance, not for drastically reducing size.

Timing: The best time to prune is in early spring before new growth starts. You can also do light trimming in mid-summer.
Technique: Never cut back into old, brown wood that has no green foliage; it may not regenerate. Always prune just above a set of green leaves or a branch junction.
Topping: Avoid cutting off the central leader (the main top branch) on a young tree if you want it to gain height. To control height on a mature tree, you can carefully reduce the leader, but this may alter its natural shape.
Shearing: For formal hedges, shear the new growth once or twice during the growing season to maintain a crisp shape. Allow the plant to be slightly wider at the base than the top so sunlight reaches the lower branches.

Common Problems That Stunt Growth

If your arborvitae isn’t growing as expected, these issues could be the cause. Early identification and action is key to saving the plant.

Bagworms: These pests create conspicuous bags and can defoliate a tree, severely weakening it and stunting growth.
Spider Mites: Cause foliage to turn yellow or bronze, reducing the plant’s ability to photosynthesize and grow.
Root Rot: Caused by poorly drained soil, it leads to yellowing, wilting, and dieback. It’s often fatal and severely limits growth before symptoms appear above ground.
Winter Burn: Desiccation from cold winds and sun causes brown foliage, which can kill branches and set back growth in spring.
Deer Damage: Deer browsing, especially in winter, can break branches and strip foliage, ruining the shape and vigor of the plant.

Selecting The Right Arborvitae For Your Height Needs

Follow these steps to ensure you choose a variety that will be the right size for your space at maturity.

Measure Your Space: Determine the available width and height for the mature plant. Remember to account for power lines, building overhangs, and property lines.
Define Your Purpose: Is it for a 6-foot privacy fence, a 2-foot garden border, or a 30-foot windbreak? Your goal dictates the size.
Research Cultivars: Use the height groups above as a starting point. Read plant tags and reputable nursery descriptions carefully for mature dimensions.
Plan for Spacing: If planting a screen, space trees based on their mature width, not their current size. For example, space ‘Emerald Green’ trees about 3 feet apart, but ‘Green Giants’ need 8 to 10 feet.
Consider Growth Rate: Decide if you need a fast solution (‘Green Giant’) or are willing to wait for a slower-growing but lower-maintenance option (‘Degroot’s Spire’).

FAQ About Arborvitae Height

How fast do arborvitae grow per year?

Growth rate depends on the variety. Dwarf types grow 1-3 inches yearly. Popular ‘Emerald Green’ grows 6-9 inches. The fast-growing ‘Green Giant’ can grow 3 feet or more per year under ideal conditions.

Can I keep an arborvitae short?

You can prune to maintain a height, but it’s an ongoing commitment. It’s better to select a dwarf or slow-growing cultivar that naturally stays at your desired height to avoid constant pruning.

What is the tallest arborvitae variety?

The ‘Green Giant’ cultivar is one of the tallest, regularly reaching 40 to 60 feet. In ideal conditions, the straight species of American Arborvitae can also achieve similar heights in a landscape setting.

How close to my house can I plant an arborvitae?

Plant at least 3-5 feet from your foundation for medium varieties, and 10-15 feet for giant varieties like ‘Green Giant’. This allows for air circulation, maintains access for maintenance, and accounts for the mature width of the plant.

Why is my arborvitae not growing taller?

Check for common issues: insufficient sunlight, poor soil drainage, compacted roots, pest infestations (like bagworms), or nutrient deficiencies. Correcting the underlying problem is essential for resuming healthy growth. Sometimes a tree is simply a slower-growing cultivar than expected.