Cedar trees thrive in various climates across the United States. These evergreen trees add ornamental value to many landscape designs. Planted in rows, these trees provide dense barriers to block wind and mark property lines. The thick boughs of cedar trees often kill plants growing beneath their heavy branches. Like many trees, cedars compete with nearby plants for soil nutrients. Knowing what types of plants to grow and following proper planting techniques ensures the health of your cedar tree and the health of the nearby plants.
Test the soil under your cedar tree. Purchase a soil test kit to determine the health of your existing soil. Cedar trees often pull valuable nutrients out of the soil, creating a need for soil amendments. Consult the results of your soil test and purchase any recommended soil nutrients.
Cut the lowest branches of your cedar tree. Use a branch saw to cleanly remove the bottom boughs and increase the amount of sunlight to the soil under your tree.
Remove any existing weeds or other plant growth in the area beneath your cedar tree. Lightly loosen the surface of the soil with a garden rake. Avoid disturbing the roots by carefully working around any surface roots. Loosen just the top few inches of soil.
Add your soil amendments by sprinkling them over the surface and raking them into the existing soil. Avoid placing mulches or other soil amendments directly over exposed roots. Covering these roots can shock and damage healthy trees.
Select shade tolerant varieties of plants to place under your cedar tree. Choose ground covers, such as sweet woodruff, periwinkle and bugleweed. Include some woodland perennials like plantain lilies, bleeding heart plants and primroses.
Place your selected plants into the soil beneath your cedar tree. Plant each variety to the depth recommended on the accompanying instructions. Tamp down the soil after planting to remove any air pockets near the roots of your new plants.
Water the plants beneath your cedar tree. Check the soil for moisture near the plants' roots. Shade tolerant plants often require moist soil conditions to thrive. Keep the soil slightly moist to encourage healthy plant growth.
Fertilize your soil regularly to provide necessary nutrients. Replace soil nutrients lost to your cedar tree's hungry roots. Apply a slow-release, nitrogen fertilizer once each year. Follow the manufacturer's instructions when applying commercial fertilizers.