Trees for Tight Spaces

'Diana' weeping larch Photo/Illustration: Jennifer Benner

Most people have an inborn need to connect with nature. But how do we make this connection in a world where houses are getting bigger and yards are getting smaller? Part of the answer, at least, is by creating gardens in the small allotment of outdoor space that so many of us have to work with. Even larger properties have small nooks, which seem like impossible spots to plant. But a narrow side yard, a lifeless courtyard, or an uninviting roof deck are all golden opportunities for a petite green space.

Small-space gardeners often encounter three basic problems: The space is jumbled and chaotic, there’s no room for variety, and the space doesn’t connect to the rest of the landscape. And as some of us have learned from dismal experience, it is better to address as many of these issues early in the game rather than late in the design process.

Small, slow-growing trees—those having all the attributes of larger ones but remaining in scale with an undersize environment—can form the backbone of small garden spaces. By carefully selecting the correct trees, a dull, wasted space can be transformed into a refuge. Luckily, today’s gardeners have a wide array of slow-growing dwarf and semidwarf trees that require little or no maintenance yet provide year-round interest with unusual color, shape, texture, bark, flowers, fruit, or cones.

‘Diana’ weeping larch
Name: Larix kaempferi ‘Diana’
Zones: 5 to 7
Size: 8 to 15 feet tall and wide
Conditions: Full sun; well-drained soil

Organize a small space with tall, airy trees

‘Tamukeyama’ Japanese maple Photo/Illustration: Jennifer Benner

When we enter a space, particularly a small or intimate space, we tend to look first horizontally, then vertically. Instinctively, we check—if only for an instant—to make sure we aren’t going to trip or misstep on something. This means it is important to keep a small space organized and not let things get too jumbled on the ground or across the field of vision.

One solution is to plant trees with an open habit: those that allow the viewer to see them and see through them at the same time. Open, airy trees act like transparent curtains, adding structure that can organize a small space into rooms or areas of interest and helping us navigate through the space.

A contorted, upright tree like ‘Diana’ weeping larch is strong enough visually to work as an accent and bold enough to separate a space, yet remains open to what lies beyond it. ‘Diana’ will eventually reach a height well above eye level, and although it has foliage down to the ground, it won’t act as a solid wall, blocking off the rest of the garden. This deciduous conifer has year-round interest, with pendulous, needled branches draping gracefully in summer; turning bright golden orange in fall before dropping; and exposing a contorted, branching silhouette in winter. It reemerges with soft, tufted, lime green needles in spring.

A deciduous tree with similar characteristics is ‘Tamukeyama’ Japanese maple. Through the growing season, ‘Tamukeyama’ maintains a consistent dark purple color better than most red Japanese maples, even in high heat and humidity. In fall, the leaves flame out to a breathtaking bright scarlet. I also like ‘Tamukeyama’ because it takes well to staking, which creates additional interest with a more open, irregular structure. As with most Japanese maples, consistency in watering is more important than volume for optimal health.

‘Tamukeyama’ Japanese maple
Name: Acer palmatum var. dissectum ‘Tamukeyama’
Zones: 5 to 8
Size: Up to 7 feet tall and wide
Conditions: Partial shade; moist, well-drained soil

Narrow, upright selections add variety without overcrowding

‘Twisted Growth’ deodar cedar Photo/Illustration: Ancil Nance

Everyone wants a national arboretum in their courtyard, but adding variety and texture without overcrowding is always an issue in a small space, particularly at ground level. As a solu­tion, consider trees that add space—visual space—to your limited area with narrow, upright habits. Trees that grow above eye level take up only a little precious yard space by, instead, claiming a certain amount of the overhead sky and helping alleviate the cramped feel common to small spaces.

Some trees ideally suited for this situation are ‘Twisted Growth’ deodar cedar and ‘Hillside Upright’ spruce. The deodar cedar has distinctive slender silver-green needles. Its branches casually droop, carving arches in the skyline. This elegant tree is drought tolerant once established in well-drained soils.

‘Hillside Upright’ spruce Photo/Illustration: Courtesy of Iseli Nursery, Inc.

‘Twisted Growth’ deodar cedar
Name: Cedrus deodara ‘Twisted Growth’
Zones: 6 to 9
Size: 8 to 15 feet tall and 3 to 4 feet wide
Conditions: Full sun; well-drained soil

The sturdy, open, lush foliage of ‘Hillside Upright’ spruce makes it a good back­drop for a smaller garden. This tree has truly unique, irregular branching. These trees, with their narrow, twisting branches, pull the eye up, expanding the sense of space.

‘Hillside Upright’ spruce
Name: Picea abies ‘Hillside Upright’
Zones: 3 to 8
Size: 10 to 12 feet tall and 6 to 8 feet wide
Conditions: Full sun; moist, well-drained soil

‘Cesarini Blue’ limber pine Photo/Illustration: Ancil Nance

For a denser upright tree that provides a bit of narrow screening, a good choice is ‘Cesarini Blue’ limber pine. If left unstaked, this tree forms a lyrical, curving leader. Alternatively, it can be kept much smaller and denser with annual pruning. ‘Cesarini Blue’ is reasonably drought tolerant once established in well-drained soils and provides an ideal focal point with its long, strikingly blue needles.

‘Cesarini Blue’ limber pine
Name: Pinus flexilis ‘Cesarini Blue’
Zones: 3 to 7
Size: 10 to 12 feet tall and 5 to 7 feet wide
Conditions: Full sun; well-drained soil

For a deciduous selection, a narrow tree like ‘Cumulus’ Alleghany serviceberry will successfully add variety to your space-conscious landscape. ‘Cumulus’ is an open upright tree, taller than it is wide, producing showy white flowers in spring, purple edible fruit in midsummer, and dramatic orange-red leaves in fall.

‘Cumulus’ Alleghany serviceberry
Name: Amelanchier laevis ‘Cumulus’
Zones: 5 to 9
Size: 15 to 25 feet tall and 10 to 15 feet wide
Conditions: Full sun to partial shade; moist, well-drained, acidic soil

‘Cumulus’ Alleghany serviceberry Photo/Illustration: Susan A. Roth

Serviceberry foliage Photo/Illustration: Danielle Sherry

Tie the landscape together with short, squat trees

‘Green Prince’ cedar Photo/Illustration: Jennifer Benner

Another problem commonly encountered when designing small spots is finding a way to provide low, space-conscious structure with trees that carry the bulk of their mass below eye level. These trees are often important in tying together the landscape and connecting it to water features, garden art, and hardscaping. Their low visual center of gravity—typically from squat or weeping shapes—makes this possible. An additional advantage to these smaller trees is that they often are the easiest and best varieties for growing in containers. Their smaller stature aboveground translates to smaller root requirements belowground.

One of my favorites for this tight situation is ‘Green Prince’ cedar. A natural bonsai, this quirky little tree takes many forms. With short, medium green needles and dramatic, irregular branching, some specimens grow up and others grow out, but all look attractive. ‘Green Prince’ cedar is a low-maintenance, high-impact small tree wherever you plant it.

‘Green Prince’ cedar
Name: Cedrus libani ‘Green Prince’
Zones: 6 to 9
Size: 3 to 5 feet tall and wide
Conditions: Full sun to partial shade; well-drained soil

‘Viridis’ Japanese maple Photo/Illustration: Danielle Sherry

Trees with a strong weeping nature anchor small gardens. A good example is ‘Viridis’ Japanese maple. The name ‘Viridis’ is used for many green laceleaf maples but always refers to a tree with narrow, deeply cut, bright green foliage. The branching is arching, pendulous, and dense, forming a low, compact, rounded dome. These trees can be as much as 8 to12 feet tall and wide but are more commonly found in the 3- to 4-foot range. ‘Viridis’ can grow in full sun (if not too hot) and turns a beautiful golden hue in fall.

‘Viridis’ Japanese maple
Name: Acer palmatum var. dissectum ‘Viridis’
Zones: 5 to 8
Size: 4 to 6 feet tall and 8 to 10 feet wide
Conditions: Full sun to partial shade; moist, well-drained soil

With the right small trees as a foun­dation, even the most disorganized and unimaginative, cramped space can be transformed into a unique garden sanctuary.