How to Create a Garden Out of a Cinder Block

While some might argue that a single cinder block planter is not a garden, anyone who just wants the satisfaction of digging in the dirt and creating a green oasis for contemplation and enjoyment would beg to differ. Because a cinder block garden is modular, you just add more cinder blocks to create the garden purist's vision. You can find free cinder blocks near demolition sites, while new blocks usually cost $2 to $5 as of November 2010.

Measuring tape

Trailing annual and perennial flowers, vegetables and herbs

Compost

Landscape cloth

Install "chimney" or "screen" cinder blocks, if available, because they provide a greater number of spaces for plants. Screen blocks and some chimney blocks have a central hole surrounded by four corner holes, while other chimney blocks have eight holes around a central hole.

Test the salt content of your compost by planting a few bean seeds in a compost-filled container two weeks before you plant your cinder block garden. Water your compost two to three times, allowing it to dry out in between, if the seedlings look stunted or have yellowed leaves.

Line a shallow basin with landscape cloth and place it under your cinder block to prevent runoff during watering, especially if your cinder block garden will be on a porch or balcony.

Fill each hole 1-inch with gravel for drainage. Top with compost to within 2 inches of the brim.

Plant one tall plant in the central hole. Plant lemon verbena, lemon balm or lemon mint, which grow 2 to 3 feet tall, for a "tea time" theme block. Try rhubarb, whose edible 18-inch stalks are used in jellies and sauces, for a "jam closet" theme.

Plant Hungarian waxed yellow peppers or sweet bell peppers in the center hole if using a "pizza garden" or "salad days" theme. Substitute jalapeno peppers if using a "taco garden" theme, or use English lavender for a "rest and relaxation" theme.

Turn the cinder block so that one corner is facing you. Plant regular, chocolate or lemon mint in the left and right corners of the "tea time" block. Substitute strawberry plants for the "jam closet" theme.

Plant trailing rosemary or peppery-tasting nasturtiums in the "pizza garden" block. Plant cilantro in the "taco garden" block. Use cherry or grape tomato varieties in the "salad days" block. Try trailing tansy for the "rest and relaxation" block.

Fill any remaining holes with short, leafy or flowering plants that fit the correct theme.

Water your cinder block garden just enough that a handful of the soil will hold together for two to three seconds in your hand, using a watering can.

Choosing a theme for your block makes it easier to select plants. "Tea time," "jam closet," "pizza garden," "taco garden," "salad days," and "rest and relaxation" are just a few possibilities.