How Tall Do Arborvitae Grow

If you’re planning a hedge or a standout specimen tree, a common question is how tall do arborvitae grow. These popular evergreens are known for reaching impressive heights, but the exact number can vary a lot. Knowing their potential helps you pick the perfect spot and avoid future headaches.

Arborvitae, part of the Thuja family, are workhorses in the landscape. They provide year-round color, privacy, and structure. But planting one without knowing its mature size is a recipe for trouble. This guide will give you clear, practical info on their height so you can plant with confidence.

The short answer is: it depends entirely on the type. Some stay shrub-sized, while others become towering giants. On average, most common landscape varieties will grow between 10 and 40 feet tall at full maturity. However, some can reach 60 feet or more under ideal conditions.

Their growth rate also varies. A ‘fast’ grower might add 1-2 feet per year, while a slow one may only put on a few inches. Let’s break down the factors that determine their final height.

Key Factors That Influence Arborvitae Height

Several things work together to decide how tall your tree will get. It’s not just about the species.

Species and Cultivar: This is the biggest factor. A ‘Green Giant’ and a ‘Danica’ are worlds apart.
Sunlight: Arborvitae need full sun for best, densest growth. In heavy shade, they grow slower and become leggy.
Soil Conditions: They prefer moist, well-drained soil. Poor, dry, or waterlogged soil stunts growth.
Climate Zone: Each type has a hardiness range. Outside that range, the plant will struggle and not reach its potential.
Spacing and Competition: Planted too close together or near large trees, they compete for resources and stay smaller.

Height Ranges of Popular Arborvitae Varieties

Here’s a look at specific types. These are typical mature heights in good conditions, but remember, extremes can happen.

Tall Giants (Over 30 feet)

Thuja plicata (Western Red Cedar): The native giant. Can soar to 60-70 feet or even 200 feet in the wild. Not for small yards!
Thuja ‘Green Giant’: A superstar for privacy. Grows 3-5 feet per year, reaching 40-60 feet tall and 12-20 feet wide. Fast and vigorous.
American Arborvitae (Thuja occidentalis): The standard. Often seen at 40-60 feet tall, though many cultivated forms are shorter.

Medium-Sized Choices (15-30 feet)

Thuja occidentalis ‘Nigra’ (Dark Green Arborvitae): A sturdy, dark-green form that typically matures around 20-30 feet.
Thuja ‘Spring Grove’: Similar to ‘Green Giant’ but with brighter color, reaching 25-35 feet.
Thuja occidentalis ‘Techny’ (Mission Arborvitae): A cold-hardy, dense variety that usually caps out at 15-20 feet.

Compact and Dwarf Varieties (Under 15 feet)

Thuja occidentalis ‘Emerald Green’ (Smaragd): A very popular narrow hedge plant. Grows slowly to 12-15 feet tall and only 3-4 feet wide.
Thuja occidentalis ‘Danica’: A true dwarf globe shape. It grows painfully slow to about 2 feet tall and wide.
Thuja occidentalis ‘Little Giant’: Another rounded dwarf, maxing out at 4-5 feet in both directions.

How to Manage and Control Arborvitae Height

You’re not stuck with whatever height they want to reach. Careful planning and maintenance gives you control.

1. Choose the Right Variety from the Start

This is the most important step. Match the plant’s natural mature size to your available space. If you need a 10-foot screen, don’t buy a ‘Green Giant’ unless you plan to shear it constantly.

2. Proper Planting for Healthy Growth

Give your tree the best start so it grows at its intended rate.

Dig a hole twice as wide as the root ball but no deeper.
Place the tree so the top of the root flare is level with the ground.
Backfill with the native soil, watering halfway through to remove air pockets.
Apply a 2-3 inch layer of mulch around the base, keeping it away from the trunk.

3. Pruning and Shearing Techniques

You can prune to control height and encourage density. The best time is in early spring before new growth starts, or in mid-summer.

Topping: Cutting off the central leader (the main upward shoot) controls height but can look unnatural. It may cause multiple leaders to form.
Shearing: Lightly trimming the new growth each year maintains a neat shape and slows vertical growth. Never cut back into old, brown wood, as most arborvitae won’t regrow from it.
Thinning: Removing select branches back to a main stem opens up the plant and is healthier than constant shearing.

4. Ongoing Care for Optimal Growth

Healthy trees grow at their proper pace. Water deeply during dry spells for the first few years and during any drought. A slow-release fertilizer in early spring can help, but avoid over-fertilizing, which can cause weak, rapid growth.

Common Problems That Stunt Growth

If your arborvitae isn’t growing as expected, check for these issues. Pests like bagworms or spider mites can weaken the tree. Diseases such as tip blight or root rot are serious and can kill branches or the whole plant. Also, deer browsing can severely damage or top young trees, limiting their height permanently.

Animal damage is often overlooked. Deer especially love to nibble the tender tops. If the leader shoot is broken, the trees growth pattern can be altered.

Planning Your Landscape with Height in Mind

Think long-term. That cute 3-foot pot can become a 30-foot monster. Always check the plant tag for mature height and width. For a hedge, space plants according to their mature width, not their size at purchase. This gives them room to grow without crowding.

Consider what’s above and below. Don’t plant tall varieties under power lines. And be mindful of roots near foundations or sewer lines, although arborvitae are generally less aggressive than some trees.

FAQ: Your Arborvitae Height Questions Answered

How fast do arborvitae grow per year?
It varies. Fast types (‘Green Giant’) grow 3+ feet yearly. Moderate types (‘Emerald Green’) grow about 1 foot. Dwarfs (‘Danica’) grow less than an inch.

What is the tallest arborvitae type?
The native Western Redcedar (Thuja plicata) is the tallest, capable of reaching over 200 feet in its native habitat. In landscapes, ‘Green Giant’ is one of the tallest commonly sold.

Can I keep an arborvitae short?
Yes, through annual pruning. However, it’s much easier to choose a dwarf or compact variety that naturally stays the size you want. Constantly shearing a giant variety is a lot of work.

How tall do emerald green arborvitae get?
The popular ‘Emerald Green’ typically matures at 12 to 15 feet tall, with a very narrow width of 3-4 feet. It’s a slow grower.

Do arborvitae stop growing?
They slow down significantly as they approach their genetic mature size, but they never truly stop growing. Very old trees will still add a tiny amount of growth each year.

What happens if you plant arborvitae too close?
They compete for light, water, and nutrients. The lower branches may die back, leaving you with a thin, unhealthy hedge. It also increases risk of disease from poor air circulation.

Final Thoughts on Arborvitae Size

Understanding how tall do arborvitae grow is the first step to success. By matching the variety to your space and providing good care, you can enjoy these beautiful evergreens for decades without suprise. Always respect their mature size. A little research before you plant saves you from major pruning headaches or even removal down the road.

Their impressive heights make them fantastic for privacy and windbreaks. With so many sizes available, there’s truly an arborvitae for almost every garden purpose. Just be sure to give them enough room to reach their full, beautiful potential.