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Arborvitae can grow anywhere from 3 feet tall to over 70 feet tall depending on the variety.
Some arborvitae stay compact and bushy while others shoot up into towering privacy screens.
So how big does an arborvitae get really depends on which type you plant and how you care for it.
In this post we will break down the mature size of different arborvitae varieties so you know exactly what to expect.
Let’s dig into how big an arborvitae gets and why that matters for your landscape.
How Big Does an Arborvitae Get by Variety
The size of an arborvitae varies widely by species and cultivar.
Here are the most common types and how big they get.
1. Emerald Green Arborvitae
Emerald Green arborvitae is one of the most popular choices for hedges.
How big does an arborvitae get in this variety? Expect 10 to 15 feet tall and 3 to 4 feet wide at maturity.
It grows slowly and maintains a neat pyramid shape without much pruning.
2. Green Giant Arborvitae
If you need a fast-growing screen, Green Giant is your pick.
How big does an arborvitae get with this cultivar? It can soar to 50 to 70 feet tall and spread 12 to 20 feet wide.
That is a massive tree, so give it plenty of room.
3. American Arborvitae (Thuja occidentalis)
American arborvitae is a native species with many named varieties.
How big does an arborvitae get when it is a straight species American? Typically 40 to 60 feet tall and 10 to 15 feet wide.
But smaller cultivars like ‘Nigra’ stay around 20 feet tall.
4. Dwarf Arborvitae Varieties
Not all arborvitae are giants. Dwarf types stay petite for small spaces.
How big does an arborvitae get if you pick ‘Little Giant’ or ‘Hetz Midget’? Usually 3 to 5 feet tall and just as wide.
These are perfect for foundation plantings or rock gardens.
5. Globe Arborvitae
Globe arborvitae forms a round, ball-shaped shrub.
How big does an arborvitae get in globe form? Around 2 to 4 feet tall and wide.
It is a low-maintenance option for borders or mixed beds.
Factors That Influence How Big an Arborvitae Gets
Even with the same variety, how big an arborvitae gets depends on where and how you plant it.
These factors can push it toward its maximum size or keep it smaller.
1. Sunlight Exposure
Arborvitae need full sun to reach their full potential.
How big does an arborvitae get in shade? It will be thinner, leggy, and possibly only half the normal height.
Plant in at least 6 hours of direct sun for best growth.
2. Soil Quality and Drainage
Rich, moist soil with good drainage helps arborvitae grow faster and taller.
How big does an arborvitae get in heavy clay or sandy soil? It may struggle, staying shorter and less dense.
Amend the soil with compost before planting to give it a strong start.
3. Watering Consistency
Young arborvitae need regular water to establish roots.
How big does an arborvitae get if it dries out often? Growth slows, and the tree may never reach its listed size.
Keep the soil evenly moist, especially during the first two years.
4. Spacing and Competition
Crowded arborvitae compete for light and nutrients.
How big does an arborvitae get when planted too close? It stays narrow and may lose lower branches.
Follow spacing guidelines: for a hedge, plant Emerald Green 3 feet apart; for Green Giant, at least 6 feet apart.
5. Pruning Practices
Regular pruning can control height and width.
How big does an arborvitae get if you never prune it? It will reach its natural maximum size.
If you trim the top lightly each year, you can keep it shorter without harming the tree.
How Long It Takes for an Arborvitae to Reach Full Size
Understanding growth rate helps you plan how big an arborvitae gets over time.
1. Slow-Growing Varieties
Emerald Green grows about 6 to 12 inches per year.
So how big does an arborvitae get after 10 years? About 10 to 12 feet tall if conditions are ideal.
2. Fast-Growing Varieties
Green Giant can shoot up 3 to 5 feet per year in good soil.
How big does an arborvitae get in just 5 years? Possibly 20 feet tall.
That is why it is a top choice for instant privacy.
3. Dwarf Varieties
Dwarf arborvitae grow only 2 to 4 inches per year.
How big does an arborvitae get after 10 years in a dwarf cultivar? Maybe 3 feet tall.
They stay small for decades.
So, How Big Does an Arborvitae Get in the End?
How big an arborvitae gets depends entirely on the variety you choose and the growing conditions you provide.
Dwarf types stay under 5 feet, while giant cultivars can exceed 70 feet.
Emerald Green hits 15 feet, American arborvitae reaches 60 feet, and Green Giant is the largest of all.
To get the size you want, match the variety to your space, give it full sun and good soil, and water consistently.
Now you know how big an arborvitae gets, so you can pick the perfect one for your yard.