How far apart should Techny Arborvitae be planted to create a screen/hedge? The garden center says 10 to 12 feet apart, but our neighbor has existing older plants that are planted 5 feet apart.
Olmsted County Minnesota
Techny Arborvitae at maturity will be 10 ft. wide if they are healthy. Therefore it is best to plant them 10 ft. apart. If they are planted closer together they will not reach their proper size. 8 ft. apart probably won't have a negative effect. Alternatively, they can be planted 4 or 5 ft apart for a very fast privacy hedge and instead of having wide full trees they will be more columnar.