- Types of Boxwood
- European Boxwood Vs Japanese Boxwood
- Dwarf Boxwood Varieties
- Tall or Large Boxwood Varieties
- Hybrid Boxwood Varieties
- Can Boxwood Grow in the Shade?
- Best hedging plants for shade
- Plants for Very Shady Sites
- Types of Shade – One: Open Shade
- Types of Shade – Two: Overhead Shade, Deciduous Trees
- Types of Shade Three – Overhead Shade, Evergreen Trees
- Types of Shade Four – Seasonal Shade
- Ah, I See. . .
Types of Boxwood
By Teresa Odle
Boxwoods (Buxus) are popular shrubs partly because they are so versatile in shape, size, leaf qualities and the list goes on. Boxwood varieties are perfect shrubs for forming hedges or showing off your pruning skills or even topiary skills on a single plant. Because they are evergreen, boxwoods make your garden look alive even when other plants are dormant for winter.
Choosing the best boxwood for your landscape might seem daunting, but keep in mind your weather, the plant’s exposure (full shade or sun, for example), and the shape or height you want for the plant’s intended use and you are likely to find the perfect boxwood.
European Boxwood Vs Japanese Boxwood
English boxwood and American boxwood are the two classic types that grow into manageable but showy hedges. Also called tree boxwood, the classic hedge plant represents the model boxwood. It is hardy down to zone 6 and a slow grower to a mature height of four feet.
American Boxwoods (B. sempervirens) , often called Common Boxwood, is a perfect all-around group of plants that continue growing for up to 100 years. Some varieties can get quite large if not cared for, but most are tall and can easily be shaped into rounded or upright form:
North Star (B. sempervirens ‘Katerberg’) is small (about 2.5 feet diameter) and evergreen in zones 5 through 9.
Jensen is another American boxwood but has a rounded shape that resembles some English boxwood varieties. Shape Jensen into a low hedge or foundation plant.
Elegantissima has creamy white edges around its green foliage and does best with afternoon shade in zones 6 through 8.
Bright green, oval leaves adorn one of the most popular types of boxwood (B. microphylla var. japonica), another great choice for formal hedges. Most Japanese boxwoods are hardy in partial sun in zones 6 through 9. Japanese boxwood has a good growth rate.
Wintergreen boxwood can take partial to full sun and grows in zones 4 through 9 and grows more quickly than many classic English boxwoods. Its leaves can turn a light bronze in winter sun.
Morris Midget is a slow grower that thrives in zones 6 through 8.
Green Beauty, also hardy in zones 6 through 8, has a slightly faster growth rate.
Dwarf Boxwood Varieties
Although many overlap with common hedge types, many dwarf boxwoods can serve as natural looking groundcover with light pruning. These flexible little plants make excellent low borders around garden beds or paths or can be shaped into round balls or hedges. Dwarf varieties also make stunning container centerpieces, and are easy to shape.
North Star Boxwood grows to only 2 or 2.5 feet tall and wide in sun or shade in zones 5 though 9.
Baby Gem Boxwood grows to only 3 feet tall and 3 feet wide, a perfect size for an accent or border in a small garden.
Wedding Ring Boxwood, a Korean variety with glossy foliage that has lime-colored edges. It grows to only 1 to 3 feet tall and wide, and is hardy in zones 5 through 8. Wedding Ring boxwood also is salt tolerant, so you can plant it near sidewalks or driveways.
Green Pillow is a dense and compact variety that grows to just over a foot in height and 3 feet across in zones 5 through 8.
Tall or Large Boxwood Varieties
Some boxwoods grow naturally upright, making them perfect for a columnar effect or taller privacy hedge.
Dee Runk (B. sempervirens ‘Dee Runk’) is an upright and fast grower in sun, shade or part sun (zones 6 through 8). Its natural growth habit forms a nice cone shape for an accent against a home or fence.
Fastigiata is similar to Dee Runk, and has blue-green foliage and upright growth, reaching up to 6 feet tall and 2 feet wide. It is hardy in zone 6 through 8 only.
Hybrid Boxwood Varieties
Breeders have created some boxwood hybrids that can take more cold than the classic varieties. If you live in USDA zones 4 to 5, you should have success with one of these special varieties. Sheridan Nurseries in Canada developed Green Gem and Green Mountain for colder climates. All of these varieties grow to average size, about 4 feet tall and 3 feet wide.
Green Gem’s foliage turns bronze in winter.
Green Mountain stays green all year long and grows upright, making it a nice cold-hardy topiary or accent shrub.
Glencoe comes from the Chicago Botanic Garden. It has uniform growth and can take any sun exposure.
Check the growing zone on the boxwoods you buy to be sure they are cold hardy or can take the heat in the location you have in mind. Most of all, happy choosing, shopping and planting!
Can Boxwood Grow in the Shade?
Boxwoods (Buxus spp.) are popular evergreen shrubs commonly grown as formal hedges or border plants for paths and driveways. They have a naturally symmetrical growth habit, making them ideal for the formal English garden style. Boxwoods are durable garden plants that require minimal maintenance if grown in a suitable location.
Most boxwood species are cold hardy to U.S. Department of Agriculture zone 5, although some cultivars grow in zone 4. Boxwood plants do best when grown in partial shade rather than full shade or full sunlight. Established shrubs may be grown in full sunlight in cool climates, but newly transplanted shrubs and plants grown in hot, Southern climates require protection from afternoon sunlight. On the other hand, too much shade can cause poor growth.
For best results, plant boxwood in a well-draining, slightly acidic sandy loam. Shrubs are also tolerant of average soils, so long the area has good drainage. Water whenever the soil is dry, and fertilize if needed. Plants that produce yellowing leaves that drop prematurely may be suffering from a nitrogen deficiency. Remedy this by applying fertilizer in the spring, but water before fertilizing to keep from burning the shrub’s shallow roots.
Thinning of branches is crucial to the health of boxwood shrubs, particularly common boxwood (Buxus sempervirens). Thinning, which can be done any time of year, helps to allow light and air into the inner foliage of the shrub, which can die if left in perpetual darkness. Shrubs that have too much inner foliage are more susceptible to pests and fungal disease. Shaping is best done in early summer. If hard pruning is required to control growth, cut the boxwood back hard in early winter.
Fungal diseases such as canker and root rot may occur. Root rot, which causes overall plant decline, rotten roots and dark leaves, is common in poorly draining, clay-based soils. Reduce watering and apply a fungicide to the soil. Increase soil drainage if necessary. Canker causes pinkish waxy fungus to appear on leaves, as well as loose, peeling bark that sits atop discolored black or gray wood. Prune out infected branches. Prevent the disease with regular applications of copper fungicide or lime sulfur.
Best hedging plants for shade
Walls and fences in shady gardens are easily covered if you know what to plant.
North- and east-facing sites can be transformed with a combination of hedging plants, which enjoy a break from the sun in partial shade. Even in deep shade there’s a choice of hedging plants that can cope with the lack of light, and even thrive, adding shape and form – from stately yew to variegated holly.
Not sure what aspect your garden is? Find out with help from our guide to the types of garden shade, and use our quick tips for planting in shade to help you along.
Discover six of the best hedging plants for shade, below.
With clipped yew in your garden, you’re assured of year-round shape and form.
Brighten up a partially shady spot with berberis, which has yellow flowers in spring, red-tinged foliage and bright red berries in autumn. This shrub makes a good informal hedge and windbreak, and a useful barrier because of its thorns.
Flowers: April and May
Height x spread: 1.5m x 60cm
Virtually all hollies will grow in a little shade. Ilex altaclerensis makes up a group of hybrid hollies that are more robust than our native Ilex aquifolium and more tolerant. ‘Argentea Marginata’ (pictured) has dramatic, golden variegated foliage that will stand out in a border. Grow them in partial to full shade.
H x S: 2.4m x 1.2m
The aristocrats of the early spring garden, camellias bring style and glamour at a time when it’s most unexpected. Shrugging off the winter cold, tough evergreen Camellia x williamsii thrives in quite deep shade and prefers acid soil.
Flowers: January to March
H x S: 5m x 2.5m
With clipped yew in your garden, you’re assured of year-round shape and form. Taxus baccata can be used as a hedging plant for shade, putting on about 30cm of growth a year, and will thrive in most soils, apart from soggy badly drained spots, and in all aspects including deep shade.
Video: How to plant a yew hedge
H x S: 10m x 6m
This handy evergreen shrub can be used to create a low hedge along boundaries in partial shade. There are many varieties of euonymus to choose from, including several variegated types, and it’s easy to clip into shape.
Flowers: May and June
H x S: 60cm x 90cm
The vibrant berries of this evergreen shrub almost glow during autumn in a shady spot. Pyracanthas make attractive hedges, or they can be trained against a north-facing wall. Small white flowers in summer are followed by orange, red or yellow berries.
H x S: 3m x 3m
More shady spots to fill?
If you’re looking for more plants for shade, we’ve got you covered. Take a look at some of the best plants for full, partial and dappled shade, plus flowering plants for damp shade.
Plants for Very Shady Sites
Hedges For Dense Shade – Shady areas, often under the canopy of other much larger plants may also be particularly dry and are often considered difficult areas in which to have colour and interest with shrubs, hedges and ground cover plants.
There are in fact many hedges for dense shade that will tolerate, or even thrive in these conditions. All of the plants below are suitable but do remember that even the most drought resistant species will need regular watering during the early stages to get established. Dry shade areas that are sheltered by walls miss out on natural rainfall whilst areas shaded by mature trees with shallow roots are constantly having any rainfall or naturel moisture absorbed by the root system of the established trees.
Most hedges for dense shade will grow more slowly in these harsher conditions, growth rates given on our website are based on a ‘good average’, in dense shade they may only grow half as fast, or even slower. With patience and given sufficient watering and mulching to get the new hedge started, good results can be achieved.
However many plants can cope with these conditions in fact will often thrive if a little forward planning is applied. Ground preparation will help new shade loving plants get established quickly adding copious quantities of well rotted manure or compost digging well into the existing soil will help as will a good layer of mulch around your plants after planting.
Adding Rootgrow mycorrhizal fungi when planting can be a very helpful aid to establishment, particularly in harsh conditions.
The most popular hedges for dense shade include all of our Berberis hedging varieties, Box, Cotoneaster Hedges and Euonymus which is available in a variety of types for shade hedges of differing sizes.
Many of our best selling evergreens are suitable including all varieties of Laurels (except the Bay Laurel), Lonicera and Vibunum tinus, a super plant for brightening dark corners producing white flowerheads during the winter months.
Our sales team are always available to answer any questions you may have about hedges for dense shade, or any of our other hedge plants, please do call our office on 01580 765600.
If you do a little research, you will usually find that Thuja Green Giant Arborvitae is listed as an evergreen that needs full sun. Yet look around, and you will see good specimens and hedges of this plant growing pretty well in shade – so what’s going on?
To understand this a little better, we need to look more closely at the different types of shade in gardens. Understanding this will help you grow not only Thuja Green Giant, but all your other plants too. Basically, there are three or even four distinct types of shade found in gardens, and each of them has a different effect on plants growing in them. Once you understand the differences you will see why it is that you see the same plant doing well in shade in one place, and badly in another, including plants of Thuja Green Giant.
Types of Shade – One: Open Shade
The first type of shade we find is what is often called open shade. What is ‘open’ about it? Simple – just look up. Can you see the sky, free of tree branches or any other obstructions? If you can, then you are looking at open shade. Even though the direct rays of the sun don’t come through, the atmosphere scatters and spread the light, and all the wavelengths of sunlight are present, in a very similar balance to direct light. This is important, and it explains why many plants will grow well in these locations. We find this kind of shade on the north side of buildings (or south side, if you are reading this in Australia, New Zealand, South Africa or most of South America) and in the shadow zone cast be trees, most noticeably between fall and spring.
Sunlight contains all the wavelengths and colors of visible light – all the colors of the rainbow. Plants use mostly red, and some blue light, but not green light. This is why they look green – the green part of the light is reflected back to our eyes, and the other colors are absorbed for photosynthesis and growth. Open shade gives plants all the necessary colors, just less of them, so growth is possible, even if it is reduced. Indeed, many plants grow very well in open shade – hydrangeas for example. Especially in hot states, and in the south, some plants prefer to be in open shade, since the very strong sunlight can burn the leaves and inhibit growth.
So if you want to grow Thuja Green Giant in a place in open shade, it may grow well. Not as fast as in full sun, and it may not be quite as dense, but this reliable plant will survive and grow, especially if it gets a few hours of direct sunlight, as we will discuss a bit further down.
Types of Shade – Two: Overhead Shade, Deciduous Trees
If you look up in this kind of shade, you will see that it comes from tree branches overhead. These may be solid and dense, or they may be more open and showing some blue sky. They may be close overhead, or high up above you. The denser and closer they are, the less light there will be. This kind of shade has another disadvantage. Most of the light that reaches the ground has passed through the leaves, and the valuable red and blue colors have been extracted by the chlorophyll. This creates that lovely cool look in shady spots – at least to us – but for plants growing in these areas the light has less value, because a lot of the ‘photon goodness’ has been taken out before it reaches them. This is why plants that will grow happily in open shade will grow less well in overhead shade.
Now, the shade from deciduous trees has some advantages, because in spring most trees are slow to leaf out, allowing much more direct sunlight through. In fall too, after the leaves have gone, light comes through, and in warmer, southern areas this is especially helpful in winter, where temperatures may be warm enough for plants to still be growing slowly. So a Thuja Green Giant, planted in the overhead shade from deciduous trees, especially in a warmer zone, may still do OK. It will certainly be a bit thin and more open, but with some trimming it should be possible to keep a reasonable look to it.
Types of Shade Three – Overhead Shade, Evergreen Trees
Now we come to the really difficult shade, the sort of thing you find underneath a big old spruce or fir tree, or a laurel bush. Not only are many evergreens very dense, allowing very little light through, but the shade is unrelenting, just as dense in fall, winter and spring as it is in summer. Gardeners know from experience just how few plants will grow in these conditions, especially if the branches are low and close to the ground. Here, Thuja Green Giant is simply not going to make it, so use something more shade tolerant, like Yew or Plum-yew (Cephalotaxus).
Types of Shade Four – Seasonal Shade
Most of us know that the sun is in the sky for longer in summer than in winter – pretty basic stuff. As well, the sun is higher in the sky in summer, especially between the two equinoxes, March 21 and September 21. Each day up until June 21 the sun is a little higher, and then it goes lower again, until everything turns around on December 21 and starts again. So if you look at your garden in winter you will see a lot of shade, from buildings and the long shadows of trees, especially evergreen ones. But as the shadows shorten, areas that were in shade are now in full sun, and this coincides with the growing season too. If you plant Thuja Green Giant in a spot that is only shady in winter, it will grow almost as well as in a spot that is sunny all year, because most of the growth happens between spring and fall, even though the plant is evergreen. If you want to know if you can make a hedge with this great plant, or plant a specimen or two, it is best to look at the available light during the summer period, as any shade in winter has very little effect.
Ah, I See. . .
It’s obvious that shade is a complex subject, and simply rules like ‘grow in sun’ have to be thought through in each garden, and the areas more closely identified. Then you will be able to plant more effectively and get ‘the right plant in the right place’. Hopefully that will mean that you can grow Thuja Green Giant in more places than you thought possible.