A good mix of large trees and smaller ones gives a landscape its shape. The big trees draw your eye up and provide a canopy; the understory trees bring the planting down toward the house and garden beds. Before adding either kind, look at the trees you already have and the space they will need as they grow.
Begin with the trees already in place
In an established yard, a mature tree may be one of the most valuable parts of the planting. It may also need attention. Look for branches crowding a structure or work that cannot safely be done from the ground, and ask a qualified tree professional to assess it before pruning. Climbing and chainsaw work are not sensible weekend chores. Our article on mature tree maintenance covers what to keep an eye on between visits.
Keeping a large tree often changes what you can plant beneath it. Check how much light reaches the ground and whether its roots leave enough room for a new bed. You may get a better result by working with the shade rather than trying to force a sun-loving planting into it.
Use small trees to connect the canopy to the beds
Japanese maples, dogwoods, cherries and smaller evergreens can give the space beneath taller trees some scale. A small Japanese maple can sit among shrubs and perennials near the house; an evergreen can hold the shape of a bed after the annual flowers are gone. Choose for the actual light, soil and available width, though. A plant sold as small today may need much more room later.
Some smaller deciduous trees benefit from occasional pruning to keep their form, and low branches may be manageable from the ground. That does not mean every pruning job should be done at home. If a branch is large or near a building or utility line, get advice first. For another look at how size and placement affect the decision, read Making a Good Tree Choice.
Leave room for the mature tree
When you lay out a new bed, check the expected height and spread of each tree rather than designing around the size of its nursery pot. Repeatedly cutting back a tree that has outgrown its spot is a chore and can spoil its shape. Look overhead for power lines, and have buried utilities located before digging. Roots and branches need room away from paving and structures too.
The same thinking applies to the whole property: the planting should make sense from the house as well as from the street. If you are planning several trees together, take a look at the existing landscape before deciding what to add.
