Small Trees for Small Gardens: What to Check First

Many people with a small yard would love a tree and talk themselves out of it, picturing roots under the patio and a canopy swallowing the whole plot. The worry is reasonable, but it is an argument for choosing carefully, not for going without. There are plenty of small trees for small gardens that stay in proportion for decades.

One well-chosen tree does more for a small space than almost any other single addition. It gives height that nothing else matches, a patch of shade to sit in, a screen at the level where overlooking windows usually are, and a focal point that changes through the year. The key is knowing what to check before you buy.

Check the mature height and spread first

The tree in the nursery pot tells you almost nothing about the tree in fifteen years. Look for the mature height and spread on the label, and ask what size it reaches at 10 to 20 years, since that is the period you will actually live with.

Spread matters as much as height. Mark the mature canopy width on the ground with a hose or a loop of string and see how much of the garden it covers. If the circle reaches over the neighbor’s side, across the only sunny bed or up against the house, choose a narrower tree.

Sizes on labels are estimates. Growth varies with soil, climate and variety, and named varieties of the same species can differ a great deal, so read the label for the exact plant in front of you.

Choose a canopy shape that fits the space

Two trees of the same height can take up very different amounts of room depending on their shape. Match the shape to the job.

• Upright or columnar: tall and narrow. Suits tight spots and side boundaries, and gives height without much shade.
• Vase-shaped: narrow at the base, spreading higher up. Leaves room to plant or sit underneath.
• Rounded: a balanced dome. The classic specimen shape, and the one that needs the most width.
• Weeping: branches that arch downward. A strong focal point, though the ground beneath is hard to use.

Consider a multi-stem form

Many small trees are sold with several stems rising from the base instead of a single trunk. A multi-stem tree tends to look lighter and more sculptural, shows off attractive bark and gives a see-through screen at eye level. In a small garden that openness is often better than a solid lollipop shape.

Think about the shade it will cast

Shade is half the reason to plant a tree and the main reason people regret one. Trees with small leaves and an open branch structure cast light, dappled shade that most plants and most people enjoy. Trees with large leaves and a dense crown cast deep shade where little will grow.

Work out where the shadow will fall in the afternoon, when you are most likely to be outside. A tree to the south or west of a seat shades it in summer; the same tree on the other side shades the neighbor’s yard instead. A deciduous tree gives summer shade and lets winter light through, which is usually what a small garden needs.

Roots, buildings and utilities

How close a tree can go to a house, wall, paving or pipe depends on the species, the soil and what is in the ground, and there is no single distance that applies everywhere. Ask a local nursery or a certified arborist about the specific tree and position before planting near buildings, walls or utilities.

Look up as well as down. Avoid planting under overhead lines, and think about where branches will be in a decade.

Ask for more than one season

In a small garden the tree is always on view, so it has to earn its place for more than two weeks of blossom. Look for at least two of these, and ideally three: spring flowers, summer leaf color or texture, fall color, fruit or berries, and attractive bark or branch outline once the leaves have dropped.

Winter is the season most often forgotten. A tree with good bark and a clean branch pattern holds the design together when everything else has died back; the guide to making a small garden work in winter covers what to look for.

Widely grown small trees

The trees below are common examples of the shapes and roles described above. None suits every climate, so check that a tree suits your hardiness zone on the USDA Plant Hardiness Zone Map, and check the mature height and spread on the label of the exact variety.

• Japanese maple: grown for leaf shape and fall color; many upright and weeping varieties.
• Serviceberry: often sold as a multi-stem, with spring flowers, berries and fall color.
• Crabapple: spring blossom and small fall fruit; varieties range widely in size and shape.
• Flowering dogwood: spring bracts, fall color and layered branches.
• Redbud: early flowers on bare stems and heart-shaped leaves, frequently vase-shaped.

Where to put it

Place the tree where it does two jobs at once. A corner position leaves the center open and draws the eye to the far end of the plot. A spot on the sight line from the main window makes it a focal point. Set between your seat and an overlooking window, the canopy screens exactly where it is needed; see privacy ideas for small gardens for how a tree combines with other screens.

Then plant underneath it. A tree is the top layer of a planting, and the guide to the best plants for small gardens suggests shrubs, perennials and groundcovers to go beneath.