Because of their wide, spreading branches and tall growth, many cedar trees cast shade down upon the garden. Some cedar trees, like the blue atlas cedar, grow up to 100 feet tall, to cast dense shade around the garden. Because of their growth habit, plants and flowers under the cedar need site requirements of both sun and shade. Versatile, most cedar trees prefer well-drained, moist soils to thrive, but tolerate a wide range of soil varieties, including clay and sandy soils.
Like the cedar tree, cranberry cotoneaster (Cotoneaster apiculatus) is an evergreen with spreading branches and a mounding form. Keeping its foliage and color all year long, like the cedar, the cranberry cotoneaster provides constant color to the garden. A slow to moderate grower, cranberry cotoneaster prefers well-drained soils, but tolerates a wide range of sites, similar to the cedar tree. Cranberry cotoneaster tolerates sun and partial shade, ideal for planting under the cedar tree that casts some shade around the garden. Cranberry cotoneaster grows 3 feet tall and 3 to 6 feet wide with small pink summer-blooming flowers, ideal for spreading around the base of the cedar tree for a burst of color. Drought-tolerant, cranberry cotoneaster has dark green leaves that turn to fiery bronze and red in fall. The bright cranberry red fruit also emerges in fall to create a prolific sea of bright red among the ground cover. The USDA Hardiness Zone for planting is 4 to 7.
Hellebores (Helleborus orientalis) are a slow-growing evergreen that thrives in light to moderate shade, perfect when planted under the commanding cedar tree. Growing 12 to 18 inches tall, hellebores, also called Lenten rose, grow in upright clumps and have a coarse texture. Appearing as if they are nodding down, the saucer-shaped blooms grow over 2 inches wide and come in a wide range of colors including, green, yellow, pink and purple. Hellebore foliage is leather-like with dark green leaves that are shiny. Remaining green throughout the winter, hellebore prefers well-drained soil to thrive. The zone for planting is 3 to 8.
Add bright bursts of color under the cedar tree with the ever-vibrant primrose (Primula x polyantha). Growing 6 to 12 inches tall, the spring-blooming flower prefers moist, shaded areas to flourish, perfect under a cedar tree. One of the first flowers to bloom in spring, primrose blooms have contrasting "eyes" that are surrounded by the bright red, yellow, blue and coral petals. Tucked under the cedar tree, this hardy perennial flower contrast with the bright green, low-growing foliage. The zone for planting is 3 to 8.