Companion Plants For A Birch Tree
Birch trees (Betula spp.) are chosen for gardens because they display colorful, paper-like or shredding bark and tend to have a bright yellow fall leaf color. Companion plants grown with a birch tree need to complement — not hide or visually overpower — the ornamental features of the birch and grow in a climate and soil that already favors the birch tree. Birch trees prosper in fertile, moist, well-drained soils in full sun or lightly dappled shade.
Ground Covers
One of the simplest and most effective design ideas to show off a birch tree is to plant a uniform carpet of ground cover plants around the tree's base. Whether the birch is solitary or planted in a grove-like cluster, a low-growing ground cover unifies the area and helps accentuate the birch. The ground cover also provides a subtle backdrop so visitors focus on the branches and ornamental bark of the birch tree.
The range of possible plant species to use as ground cover is large and depends on soil quality and moisture, as well as how much light the birch tree allows to reach the ground beneath. The U.S. Forest Service suggests ground cover plants including bugleweed (Ajuga reptans, USDA zones 3-10), hosta (Hosta spp.), foamflower (Tiarella cordifolia, USDA zones 3-8), lilyturf (Liriope spp.), tickseed (Coreopsis spp.), and creeping juniper (Juniperus horizontalis, USDA zones 3-9).
Evergreens
Contrast the birch tree's tall height by planting evergreen shrubs or trees. Birch trees are particularly showy in winter, when the tree's silhouette is obvious and an unimpeded view of the bark exists. A background of a dark green evergreen hedge or trees like Eastern white pine (Pinus strobus, USDA zones 3-8), Austrian pine (Pinus nigra, USDA zones 4-7), hemlock (Tsuga spp.) or American arborvitae (Thuja occidentalis, USDA zones 2-7) accentuates the lighter-colored branches and trunk of the birch.
Evergreen shrubs scattered around the base of a birch tree help provide visual color and structure to complement the upright trunk. Juniper (Juniperus spp.), mugo pine (Pinus mugo, USDA zones 2-8), dwarf blue spruce (Picea pungens 'Glauca Globosa,' USDA zones 2-7), and Russian arborvitae (Microbiota decussata, USDA zones 3-7) are a few needled evergreen shrubs to grow near a birch tree.
Flowering Shrubs and Bright Bushes
Birch trees produce small, bright flowers in early spring, but for the most part they aren't considered an ornamental flowering tree. Once the birch tree's leaves return in spring and summer, a few strategically placed flowering shrubs can bring flowers and brightness back to the area around the tree. Choose round-shaped shrubs to contrast with the vertical nature of the birch, and plant taller shrubs behind the birch and shorter, petite flowering plants in the foreground.
The U.S. Forest Service mentions using dwarf lilacs (Syringa spp.), rhododendrons/azaleas (Rhododendron spp.), viburnums (Viburnum spp.) and spirea shrubs (Spiraea spp.) to make a colorful splash. While the flowers of winterberry holly (Ilex verticillata, USDA zones 3-9), blueberry (Vaccinium spp.), beauty berry (Callicarpa spp.) and red-twig dogwood (Cornus spp.) shrubs are often overlooked as companion plants, the wintertime berries or leafless colored stems can provide a visual contrast to the ornamental bark of the birch tree. This makes the entire planting area around the birch a striking highlight in fall and winter.