Landscape Architecture
Installing Mature Trees in Your New Landscape
The living part of your landscape can take years to grow in. That’s why we love including mature trees in a fresh landscape — they immediately provide the shade, privacy, and impact of an established garden. If you’re thinking about installing a mature tree in your outdoor spaces, here is what you’ll want to to consider.
October 30, 2025
When the construction of your new outdoor area is complete, the hardscape features, like patios, decks, and paths are ready to enjoy right away. But the living parts of your landscape, especially trees and large shrubs, are just getting started.
For the most part, they won’t their full size and beauty for many years. In some cases, you may be waiting close to a decade to enjoy the shade, privacy, or structure that those plants are intended to provide.
What do you do if you want to enjoy these benefits now? The quickest way to accelerate the timeline to your full-grown outdoor spaces is to install mature shrubs and trees.
In addition to immediate screening, shade, and impact, larger plant material also gives a new project the timeless character of a mature, established garden. Trees can be particularly impactful, given their size and the character they immediate add to an outdoor space.
As with all choices made during the design of your landscape and site, choosing to include mature trees comes with a variety of considerations and impacts. Here is how we go about choosing and installing large trees for our clients.
Selecting the right tree.
The first consideration is the selecting the right tree. Several criteria should be considered when installing any tree, but especially when installing a larger, more mature one to your landscape.
- Mature size and growth rate.
- Leaf texture and density.
- Fall color and seasonal flowering.
- Branching pattern.
- Maintenance and long-term health needs.
- Site access and equipment requirements for installation.
- Proximity to buildings and utilities.
- Overhead clearance.
We take these criteria into consideration for all trees, but mature trees need to meet all your site’s requirements at installation. For example, in Seattle, trees should be planted at least five feet from buried utilities and ideally about 25 feet from other nearby large canopy trees.
If planting under power lines, we recommend sticking to species that mature under 25 feet. These requirements will influence what mature trees work for your sight as much as their beauty and visual interest.
And if a particular species is simply too large to even get onto your site, it won’t be an option no matter how lovely it might be.
Regional Tips for Puget Sound
Your regional location might also call for some specific considerations. Here in the Pacific Northwest, and particularly in the Puget Sound region, we think about the following.
- Fall planting between October and December is best. Winter rains help new roots establish before summer drought.
- Certain native trees, like Pacific madrone, are notoriously difficult to transplant as large specimens. Smaller stock establishes better.
- For screening, western redcedar has historically been popular, but with climate-driven dieback in some areas, we suggest drought-tolerant alternatives.
We work through these regional considerations during the design process and use the information to identify ideal trees.
Once we have a good idea of what will work for a project, we visit local nurseries to review available mature trees, hand-selecting and tagging each tree that will best fit the landscape design. Homeowners often join us on these nursery visits! It’s a fun and rewarding part of the process.
Preparing the tree.
The next step is to prepare the tree. Unlike container-grown plants, large trees are grown in the ground, with roots extending far beyond their canopy. To prepare them for moving, nurseries “dig” the trees into balled-and-burlapped (B&B) root balls sized by industry standards.
- 24" root ball diameter for a 2” trunk caliper.
- 32" root ball diameter for a 3” trunk caliper.
- 42" root ball diameter for a 4” trunk caliper. These trees often weigh in at over 1,000 pounds.
Because root loss is stressful for the tree, timing matters. For most deciduous trees (the ones that have color-changing leaves), the safest window is during dormancy, from late fall through early spring.
Nurseries may root-prune months in advance to encourage new, fine roots inside the eventual root ball. This makes transplanting safer, improves survival rates and, if the construction schedule allows, is our preferred approach.
Installing the tree.
The scale of mature trees means installation requires careful logistics and preparation. A successful transplant starts with proper site preparation.
- A planting hole 2–3 times wider than the root ball, but only as deep as the root flare (the area where the main roots meet the tree trunk).
- Stable, compacted soil beneath the root ball so the tree doesn’t sink.
- Grading to direct water away from the trunk.
- Using only native soil for backfilling. Soil amendments (anything physical or chemical added to the soil) can create “bathtubs” that hold water around roots.
- Adding 2–4 inches of arborist wood chips over the planting area to conserve moisture and regulate soil temperature.
We always conduct a site review before installation to check drainage, utility clearances, and access for equipment.
On installation day, your contractor will need to have the proper equipment on site. Smaller trees may be moved on dollies, but 1,000-pound B&B trees often require forklifts or cranes.
We’re also on site on installation day to align the tree for the best views and sun orientations, confirm the root flare sites slightly above grade, remove all the twine and cut away the burlap and wire from the top of the root ball, and observe the backfill, which needs to be done in layers, watering after every layer to gently settle the soil and remove air pockets.
Immediately after the tree is installed, drip irrigation rings or bags must be installed, as well, to deliver slow, deep watering where roots need it most.
Ongoing care.
After your mature tree is installed, the work doesn’t end. The first 2–3 years are critical for survival and growth.
Watering Schedule
For the first two weeks, your new tree needs daily watering. For the next two to three months, it needs watering every two to three days. Weekly waterings, or more during summer droughts, is needed for up to two years after installation. A good rule of thumb is 1–1.5 gallons of water per inch of trunk diameter per watering.
Staking
We advise staking only for high-wind or unstable sites. Staking should be removed as soon as possible, usually within a year.
Fertilization
Skip fertilization at planting and instead focus on water and mulch. Fertilize only after soil testing shows need, usually after 2+ years.
Inspections
Seasonal check-ins are necessary to monitor for pests, diseases, or settling, and help secure the long-term health of your investment.
A tree is considered “established” when roots extend well beyond the planting hole. This typically takes place in 1–1.5 years per inch of trunk diameter.
Even in their first season, mature trees bring permanence and a sense of time that smaller plantings can’t match. To make sure you protect your investment, acquiring the right species, ensure it is prepared and installed in the proper manner, and commit to the maintenance required to keep it healthy and thriving. And don’t be afraid to call up your landscape architect to help!
