Garden Variety: For evergreens in Kansas, think beyond pine trees
Pine trees are often the first things that come to mind when thinking about evergreen plants to add to the landscape for screening, windbreaks and winter interest. There are many other options, though, and many are better suited for planting in northeast Kansas than pines.
Take a look around the yard this winter while the leaves are off most trees and identify areas that could benefit from the beauty and shielding that evergreens provide. Then consider the options.
The terms pine and evergreen are sometimes thought to be synonymous. Pine refers to a specific group of trees, while evergreen is a broad term used to describe plants that retain their leaves through the winter. Evergreens may have needles (pine and spruce), scale-like needles (cedar and arborvitae), or broad leaves (boxwood, yew, some viburnums and magnolias).
The only native evergreens in Kansas are eastern redcedars and inkberry holly. They are the hardiest options for this area but are sometimes overlooked because they are considered less attractive than other options or are too common.
Eastern redcedar has considerable variability, but it is the most reliable evergreen to fill any landscape need in this region. For landscape plantings, consider using cultivars that have been selected for their shape, size and color. Canaerti is a columnar tree that grows to about 20 feet tall and can range from 6 to 15 feet wide. Prairie Sentinel is a little shorter and narrower than Canaerti, and Taylor is a very narrow upright cultivar. Grey Owl is only about 3 feet tall by 6 feet wide at maturity. For a windbreak, wild transplants or seedlings from the Kansas Forest Service are affordable options.
Inkberry holly is a good choice for winter interest in the landscape but offers little screening. Try Chamzin, which is about 4 feet tall and wide, or Shamrock, which is a little taller.
Nonnative evergreens that have proven their worth in northeast Kansas include selected species and cultivars of arborvitae, bayberry, boxwood, juniper, magnolia, spruce, viburnum and yew.
Arborvitae has scale-like needles like redcedar and juniper, although they are softer and more rounded on arborvitae than on the other species. They range in size from 2-foot-tall shrubs (Little Giant) to 30-foot trees such as Green Giant. These plants are susceptible to fungal disease and dislike certain soil types, but they are still a popular choice of many landscapers.
Bayberry is a large shrub (10 feet tall at maturity) with glossy, aromatic leaves. This plant gets wider over time if suckers are left to grow, making it a good choice for an area where it has plenty of room to grow. It is attractive, provides screening and is underused because of its size and availability.
Boxwood is a commonly planted shrub ranging in size from 3 to 15 feet depending on the cultivar. Smaller varieties are good foundation plantings and hedges. Larger varieties are harder to find but provide excellent screening.
Junipers are also common and have a wide range of variability. Use short, shrubby species for evergreen groundcovers, foundation plantings and hedges. Use taller shrubby species or tree-form junipers for vertical winter interest, screening and windbreaks.
Bracken’s Brown, Edith Bogue and other magnolias that have been selected for their cold-hardiness provide winter interest and screening. They benefit from supplemental watering over extended dry periods and especially need water in winter to prevent scorching.
Spruce is a tree that landscapers either love or hate. It can survive for a long period of time with a very compact root system, but that means it might die several years after transplanting because the roots failed to grow into the soil outside of the planting hole. If spruces do establish in a site, they grow to beautiful medium or large trees. Like magnolias, spruces benefit from supplemental watering over extended dry periods year-round.
Prague viburnum has leathery evergreen leaves, and leatherleaf viburnum has leaves that are semi-evergreen. Both are 10 to 15 feet tall at maturity and provide excellent winter interest and screening.
Yew is a common foundation and hedge plant similar to boxwood. There are large options such as Hicksii, which grows to 15-20 feet.
Atlas and incense cedars, falsecypress (chamaecyparis) and holly may also be suitable evergreens in Kansas but are much more finicky about site conditions. Consult with a professional to minimize risk of losing these investments.
Despite all these choices, some gardeners still want pines. They were recommended for several decades for screening and windbreaks, but the discovery of pine wilt disease changed their favorability. This disease is native to the region and shortleaf pine (native to Missouri) is resistant. Pine wilt attacks nonnative pine species and kills them quickly after infection.
Although shortleaf pine is resistant to the disease, the species is rarely planted because it is less attractive than others.
Limber pine (Vanderwolf’s pyramid is one cultivar) may be resistant to pine wilt, but it’s not a sure bet. Eastern white pine is somewhat resistant but has problems with poorly drained alkaline soils that are common in this region. Scotch, Austrian and ponderosa pines are highly susceptible and should be avoided. For other pine species and cultivars, research about disease resistance and suitability for growth in Kansas are ongoing.
— Jennifer Smith works in regulatory horticulture and has worked as a horticulturist for various government entities. She has experience in landscape design and maintenance and as an educator.