How to Garden in Cinder Blocks

Start your planting in spring after last frost. These plants don't need the soil to thaw, but do require warm air temperatures. Wait for night time temperatures of 60 to 65 degrees F to ensure safety for all summertime fruits, vegetables and annuals.

Place your cinder blocks in level, safe locations with appropriate lighting conditions. Choose areas with six to eight hours of sun every day for sun-loving plants and dappled shade for shade-loving plants. In this raised garden situation, site drainage is irrelevant. Make sure that the cinder blocks sit securely on the ground. Scatter the blocks around the yard for decorative effect. Stack two cinder blocks, on on top of the other, for large vegetable plants like tomatoes, peas and beans, which require more root room.

Mix equal parts organic compost and garden loam for your potting soil, and fill the cinder block holes to the top. This mixture provides nutrition and drainage, and retains moisture between waterings. Add 10-10-10 or 12-12-12 granular fertilizer to vegetable cinder blocks, and 5-10-5 granular fertilizer to annual flower cinder blocks.

Plant small annuals like primroses, aster, cornflowers, petunias, pansies, sweet peas, geraniums, mums and cosmos in the sun, and violets and impatiens in the shade. Plant small vegetables like radishes, beets, spinach and cabbage in shaded areas, and larger plants like tomatoes, peas and bush beans in sunny areas. Plant strawberries in full sun for a fruit addition.

Water the garden with 2 inches of water every week to maintain soil moisture, and fertilize the plants on individual schedules. Deadhead annual flowers as the blooms fade to encourage repeat blooming.