Tree planting tips

Planting native trees is not difficult. Here are some key points:

Consider the timing. Fall is the best time to plant, after the tree has lost its leaves. This gives the roots, which keep growing in the winter, a chance to move out into the surrounding soil before summer hits. Early spring while the tree is still dormant is okay as well. Don't plant between May 15 and the end of September.
Pick a good tree for your location. Check that it will fit your site when it grows, and remember that roots also need a lot of room. Find details here on site selection. Learn about native tree choices here, and for help picking the tree species, you can consult our tree choice "hotline."

Remove all tags, wires, burlap, etc.

Prepare trees grown in containers by “squaring the ball:” cut 1.5 inches off the surface roots from top to bottom on all sides. This works much better than splaying or scoring the surface.

Don’t add “better” soil. You don’t want the roots to decide to stay inside the hole. Native trees prefer local soils anyway.

Check to make sure the top of the soil around the tree is at the root flare. Sometimes trees are potted too deep, so dig down to make sure.

Dig a hole two or three times as wide and the same depth as the roots.(For bare root seedlings, though, all you need to do is make the hole deep enough to spread the roots.) Deepen the outer edge of the bottom to make a central pedestal. "Deglaze" the hole by roughing up the walls. Spread the young tree’s roots and place it in the hole so the root crown is exactly level with the surface. Add the soil back to the hole, a little at a time, watering as you go to settle the soil around the roots.

Mulch lightly to control weeds - 4 inches of fresh wood chips (preferred) or 2 inches of wood (not bark) mulch - but don’t pile mulch up to the tree trunk. Leave a gap between trunk and the mulch. DO NOT pile mulch around the tree trunk – “mulch volcanoes” cause rot and can be home to mice and rats. They also cause the tree to put out roots higher up than they should.

Prune ONLY dead and broken branches.

Do not stake the tree unless absolutely necessary, and then only loosely and for one year at most.

Water regularly until the tree is established. The younger the tree, the easier the watering task.
- Bare root seedlings: Add a gallon of water after planting. Repeat in 2-3 weeks if there has been no rain. After that, in you are planting in a natural area or using arborist wood chip, no need to repeat unless there is no rain for 6 weeks. If you chose to use finely ground landscaping mulch (not a great choice for trees, since it forms a water and vapor barrier), you'll need to continue to check for dryness and water accordingly. Expect a certain failure rate from small seedlings.
- For larger specimens, the ideal schedule is to water every day initially and then weekly (unless there has been a soaking rain), continuing until the roots have grown out into the soil. Typically this takes 1 year for every 1 inch of tree caliper. In other words, a tree with a 2-inch trunk will take 2 years to establish! Saving on work is only one of the good reasons to buy smaller trees. See www.treesaregood.org for more information on tree care and planting.
- If you are unable to maintain this schedule, you'll need to check the soil moisture carefully to water when needed. An inexpensive moisture meter is very helpful. (Watering is suspended once the leaves fall off, assuming normal rainfall.)
- Do not water if the root ball is wet or saturated. Overwatering is as bad for trees as underwatering. Heavy rainfalls count as watering.
- Water deeply around the edge of the planting hole to encourage roots to reach for the water, using ten gallons per inch caliper.

Plant when young - it takes one year per inch caliper (diameter at 6 inches above the ground) for trees to establish, and they will need watering that entire time. The smaller the tree, the less watering is needed. Smaller trees also transplant better. They are likely to need some pruning after they get established to direct their growth properly - read about it here, and be sure to make a note to yourself to do it at the proper time.\

Young trees may need protection from deer.

After getting established (one year for seedlings and very small saplings, two or three for larger trees), well chosen native trees require little or no care, because they are perfectly adapted to local conditions.

More details about native tree planting and maintenance can be found here on the Plant NOVA Natives website, and in the Fairfax County Tree Basics booklet.