Conifers are commonly evergreen and reproduce through the formation of cones. Their growth rate is generally divided into three categories. Slow-growing conifers grow less then 12 inches per year. A medium or moderate growth rate is between 1 and 2 feet per year. Fast-growing conifers grow at least 2 feet per year. Conifer growth rates differ not only from species to species but from species to hybrid cultivar.
Cedrus and Chamaecyparis
Atlas cedars, C. atlantica, grow quickly for 10 to 20 years then slow down, eventually reaching a mature height of 40 to 60 feet. The Glauca Pendula cultivar grows slowly with a weeping habit. It is often used in espalier. C. deodara or deodar cedars also grow quickly during the first 10 to 20 years, rarely growing to more than 50 feet tall. The Pendula or Prostrata cultivar grows with a weeping habit to 10 feet tall or less. Cedar-of-Lebanon, Cedrus libani, grows slowly to a mature height of 40 to 50 feet.
Chamaecyparis pisifera or Japanese falsecypress grows slowly to a mature height of 25 to 50 feet. The Filifera or Sawara cultivar grows to between 25 and 35 feet. C. nootkatensis or Nootka cypress grows slowly to between 50 and 75 feet. C. obtuse or Hinoki falsecypress grows to between 50 and 75 feet tall at a medium rate. C. thyoides or Atlantic whitecedar falsecypress grows to 50 feet tall at a medium growth rate.
Abies and Juniperus
Abies balsamea or balsam fir grows slowly to a mature height of 50 to 60 feet. The Nana cultivar grows to only 2 feet. A. fraseri or Fraser fir grows slowly to a mature height of 30 to 40 feet. The Klein's Nest cultivar grows to only 3 feet. A. procera or noble fir trees grow at a slow-to-medium rate to between 50 and 100 feet tall.
Calocedrus decurrens or California incense-cedar grows slowly to a mature height of 40 to 60 feet. It is not a true cedar and is actually in the juniper family. Juniperus scopulorum or Rocky Mountain juniper grows slowly to a mature height of 30 to 40 feet. J. ashei or ashe juniper grows to 35 to 40 feet tall at a medium rate. J. virginiana or Eastern redcedar, also a type of juniper, grows fast to a mature height of 40 to 50 feet.
Picea and Pinus
Picea abies or Norway spruce has a fast growth rate early on but slows down as it ages. It matures to 40 to 60 feet tall. P. abies "Nidiformis" or bird's nest spruce grows at a slow rate to only 3 to 6 feet tall. P. glauca or white spruce grows at a medium rate to between 40 and 60 feet tall. Some P. glauca hybrid cultivars like Echiniformis and Jean's Dilly grow slowly.
Pinus banksiana or Jack pine grows slowly to a mature height of 25 to 50 feet. P. sylvestris, Scots or Scotch pine, grows to between 30 and 50 feet tall at a medium growth rate. Scotch pine hybrids Aurea, Beauvronensis and Spaan's Fastigiate grow slowly. P. strobus or eastern white pine is a fast-growing conifer that matures to between 50 and 80 feet tall, although the Sea Urchin hybrid cultivar grows slowly.
Thuja and Tsuga
Thuja occidentalis or white cedars are slow-growing conifers that eventually reach a height of 25 to 40 feet. T. orientalis or arborvitae grows at a medium rate to a height of 15 to 20 feet. T. plicata or giant arborvitae also grows at a moderate rate but commonly reaches a mature height between 50 and 70 feet.
Tsuga Canadensis, eastern or Canada hemlock, grows slowly to a mature height of 50 to 70 feet. T. caroliniana or Carolina hemlock also grows slowly to between 50 and 75 feet. Tsuga diversifolia or Japanese hemlock grows at a medium rate to a height of 50 to 75 feet.