Arborvitaes love the sun and moist well drained soil. They are moderate growers but can be hurried along with adequate moisture and fertilization. This also minimizes spring and fall interior shedding. They also are less prone to bag worms and other pest than leyland cypress.
To create a solid screen, space plants 2 to 3 feet apart. To emphasize their columnar shape, plant 4 to 5 feet apart and plant lower growing shrubs such as knock out roses, loropetalum or dwarf forsythia in between and a little to the front. If you need a physical barrier but wish to keep your sight lines open, inter-plant with rotunda or Carissa hollies.
Proper watering is critical in your first summer. Soak the plants well when you plant them and mulch to help retain moisture. Water deeply every 3 to 4 days when there is no rainfall. A rain gauge is an inexpensive investment. One inch of rain a week is usually sufficient for most plants. Pay particular attention to plants on a slope. Those at the top may receive too little moisture while those at the bottom may get too much.
Arborvitaes generally do not need to be pruned, but they do take shearing and shaping well, hence their popularity as topiaries. You can accentuate their conical shape and keep them to a uniform size with a yearly shearing in late winter. As with all evergreens, do not cut back into the bare branches. They will not regenerate from such excessive pruning.
Green Giant arborvitae (Thuja plicata x) is a columnar tree perfect alternative to leyland cypress for screening purposes. The are a great choice for creating a private space in your yard. They are capable of withstanding ice, snow and other extreme weather.
The Emerald Green arborvitae (Thuja occidentalis ‘Emerald Green’) is a naturally columnar shaped evergreen. It has dense bright green fan like foliage that takes on a bronze hue in winter. It will reach 10 feet tall and only 3 feet wide in a few years, though it will get larger with time. It is a great choice where space is at a premium. They are the perfect screening shrub. They can help you achieve some privacy in your yard whether you just want a hedge along your property or you’d like to block out your neighbors.