- 1). Choose the style of landscaping bed. A curved bed usually looks best under trees. Outline the desired area using non-toxic spray paint. Base the size of the bed on the size of the tree. For example, a small crabapple tree should have a smaller bed than a large oak.
- 2). Remove any existing grass, weeds or other plants, including plants' roots, inside of the outline. Don't use a weed killer that could damage the tree or new plants you install. Try not to damage tree roots while removing plant material.
- 3). Spread a 2- or 3-inch layer of compost on the bed. Work it into the top 4 inches of soil with a shovel. Use care around tree roots.
- 4). Install edging. Edging keeps mulch in, prevents grass from encroaching and gives the bed a finished look. Edging choices for under a tree include rock, wood and pre-formed concrete. Avoid edging material that you have to pound into the ground. Alternately, create a natural edge using a spade to cut the dirt at an angle while being careful of roots.
- 5). Select and purchase plants for the landscape. Check that each selection will grow in your USDA hardiness zone. Choose plants that tolerate full to partial shade and moderately dry to dry soil.
- 6). Situate the plants in the bed while still potted to visualize where you want to plant them. This allows you to move them around and find a design that works. Place taller plants closer to the tree and graduate to smaller plants near the edge. Leave enough room for plants to reach their mature size without crowding each other.
- 7). Install the plants. Dig holes approximately twice as wide as the pot and deep enough so the plant crowns sit at soil level. If you encounter large tree roots while planting, relocate the plant rather than cut the root. Place the plants in the holes and water until the hole fills up. Once the water drains, backfill with a mix of half soil and half compost.
- 8). Spread a 3-inch layer of mulch. Shredded hardwood mulch works in most situations; however, under an evergreen you might want to use pine needles or bark mulch for a cohesive feel. Mulch retains water, decreases soil erosion, maintains soil temperature, adds nutrients and prevents weed growth.
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