The arborvitae growth rate depends on the variety you plant. Some types creep along at a few inches a year. Others shoot up by several feet in one season. There is no single answer, because the name "arborvitae" covers slow species and fast hybrids that do not act alike at all.
Two arborvitae bought the same day from the same shop can stand at very different heights five years later. One stays a tidy little column near eye level. The other looms overhead like a small tree. A slow species and a fast growing arborvitae hybrid just do not grow on the same clock.
The American species and the popular Emerald Green sit on the slow end. The USDA Forest Service lists the native white cedar as a slow grower. Young plants often add only about 3 inches a year in their early seasons. That slow pace is why Emerald Green stays neat. It rarely needs heavy pruning to hold its shape.
Soil, water, and sun shift these numbers too. A well-fed plant in full sun grows near the top of its range. A dry, shaded, or root-bound one slows way down. But the variety still sets the ceiling. No amount of care turns a slow Emerald Green into a fast screen, and a Green Giant stays quick even in plain soil.
The Green Giant hybrid plays a different game. This type can add a fast 3 to 5 feet of height per year once its roots settle in. That Green Giant growth rate is why landscapers reach for it when a client wants a tall privacy screen in a hurry. The wait drops from many years to just a few.
Mature size tells the same story. Emerald Green tops out around 12 to 15 feet over many seasons. It holds a narrow shape the whole time. Green Giant can reach 40 to 60 feet far sooner and spreads much wider at the base. So the word "fast" only fits certain varieties. The arborvitae growth rate you get tracks the cultivar, not the label on the bin. Pick the wrong one for your space and you face real headaches later.
There is one more slow type worth knowing. Techny, sometimes sold as Mission, grows at a moderate pace and lands between the two extremes. It adds maybe 6 to 12 inches a year and tops out near 15 feet. So even within the slow camp, the speed shifts from one cultivar to the next. The tag is the only place those exact numbers live.
Spacing matters once you know the speed. A fast Green Giant needs 5 to 6 feet between plants so each one has room to fill out. Crowd them and the inner branches go bare from shade. A slow Emerald Green can sit closer, around 3 feet apart, since it stays narrow and never bulks up the same way. The growth rate drives the layout.
Read the plant tag before you buy instead of assuming every arborvitae grows fast. The tag lists the variety name, the yearly growth, and the mature height. Those three numbers decide what your yard looks like in ten years. A slow Emerald Green will never fill a 30-foot gap. A Green Giant will swallow a small bed in no time.
Match the variety to the job and you dodge both problems. Want a quick screen along a back fence? Plant Green Giant and give each one room to spread. Want a low-fuss accent near the house? Pick Emerald Green and enjoy the slow, steady pace. Knowing the arborvitae growth rate up front turns the whole question of speed into a simple choice you make once.
Read the full article: Arborvitae Shrub: Complete Growing Guide
