Korean Boxwood ‘Wintergreen’ (Buxus sinica var. insularis Wintergreen) tends to stay green in winter and is hardy to Zone 4. The leaves are not as fine as on Buxus sempervirens, but it is still a beautiful boxwood.
Wintergreen Boxwood is an excellent alternative for those who love boxwood but live in places where English boxwood is not hardy.
Korean Boxwood ‘Wintergreen’ is aptly named.
Introduced in 1960, Buxus ‘Wintergreen’ is a slow grower, it is true, but eventually reaches 4′-5′ feet tall/wide after 10-15 years. ‘Wintergreen’ stays green through the winter, and is a fantastic choice for gardeners who cannot stomach another winter of pumpkin orange boxwood. For gardeners where other boxwood species and cultivars are borderline cold-hardy, Wintergreen will allow you to sleep soundly on cold nights rather than fretting or coddling.
I really love English boxwood. Sometimes, for a number of reasons, we need to look to the American, Japanese and Korean boxwood for answers. Perhaps we need a cold-hardy boxwood (The plant featured on this page, ‘Wintergreen’, is cold hardy to Zone 4; English boxwood borderline to Zone 5). Perhaps we tire of seeing our boxwood grow half an inch a year (American boxwood can get huge).
Boxwood and winter-burn
Boxwood culture in the garden is fairly consistent across the board. Before getting into some basic planting rules, the most important thing is to prevent desiccation by protecting the boxwood from micro-climates in your landscape prone to wind. Desiccation can happen during any season of the year, but with boxwood, we are primarily discussing winter-burn.
The orange boxwood effect, while it is true some varieties are more prone, is mainly a product of growing conditions. Wind, low soil moisture, and low temperatures combine to create a situation where the roots of the boxwood cannot take up water faster than is lost through transpiration. You cannot control the outside temperatures, but you can protect your plants from wind through prudent design, and you should water your plants, even in winter, until they are established (nevermind on the watering if the ground is frozen).
Planting & Caring for Boxwood
The best time to plant boxwood is in fall or early spring. What most garden guides do not tell you is that landscape companies plant year-round, but beware that plants installed in the active growing season must often be watched over carefully. Sun is normally fine; partial shade is even better…if you plant in heavy shade plants may be more open than preferred, especially important with boxwood considering it is beloved for the tight growth.
Dig a hole slightly more shallow than the rootball, as our aim is to plant with the top of the rootball just an inch or three above the natural grade. If you have the ability, amend the soil in the area with compost. Plunk the boxwood in the hole, backfill, and water.