Growing strawberries (Fragaria × ananassa) in the garden not only supplies your family with fresh, sweet berries each summer, but it provides a good opportunity for teaching your children about gardening, nature, responsibility and work. If your yard contains poor soil or lacks enough space for a full strawberry patch, don't despair. A spiral strawberry planter acts as a raised bed, holding rich, plant friendly soil while allowing you grow more plants per square foot. If you live in one of the U.S. Department of Agriculture plant hardiness zones 3 through 10, the regions in which strawberries grow, building a spiral planter for your strawberries will allow you to cultivate a healthy crop.
Pull weeds and remove debris from an area that receives at least 6 hours of full, direct sunlight and contains fast-draining soil. Using a stick, draw a circle with a diameter of 6 feet in the soil.
Place one end of the stick in the line of the circle where you wish the spiral to begin. Draw a line in the soil to mark the spiral inside the circle, making 1 1/2-inch passes around the circle to create a three-tiered spiral. Space the lines of the spiral 15 inches apart to allow enough width for the rows and walls.
Dig 3 inches down with a shovel or trowel over the marked lines of the circle and spiral to create a trench for the base layer of blocks. Make the trench 3 1/4 to 3 1/2 inches wide.
Line the trench with a single row of bricks or pavers. Push the individual bricks together so that the inside corners of their ends touch, leaving a triangular gap between their outer corners so that they will fit in the circular trench. Fill in the trench around the sides and gaps between the bricks with soil, tamping it down to secure the bricks in place.
Stack a second row of bricks on top of the first row, lining the bricks up as before. Alternate the ends of the bricks with the brick ends in the previous row to create a staggered pattern. Repeat this process to stack a third row of bricks on the second row in the same staggered pattern.
Pour topsoil or potting soil into the spaces between the brick walls. Fill the areas to 1 inch below the top surface of the topmost bricks. Tamp the soil down to set it. Add additional soil if needed to maintain the correct level. Tamp the added soil down.
Stack three additional rows of bricks on the bricks in the second and third tiers of the spiral, increasing their height about the outermost circle. Stagger the bricks as before to ensure a sturdy wall.
Pour topsoil or potting soil into the space inside the second and third tiers of bricks, filling them to 1 inch below the brick's tops. Tamp the soil down to settle it.
Stack two to three rows of bricks on the bricks in the third tier to raise it above the second tier. Fill the space inside the third tier with soil, stopping when it reaches 1 inch below the brick's tops. Tamp the soil down as before.
Spread 1 teaspoon of 10-10-10 nitrogen, phosphorous, potassium granular fertilizer per square foot of soil along the rows of the spiral planter. Mix the fertilizer into the top 6 inches of soil with a trowel. Smooth the soil's surface with a garden rake, and tamp it down.
Select a strawberry start, and trim all of its roots to a length of 8 inches. Dig a hole in the center of the top tier of the spiral planter, making it twice as wide and equal in depth to the start's root system.
Place the start in the hole. Adjust the depth of the hole if needed to position the start's crown, or point where the roots and shoots meet, just above soil level. Fill the hole with soil, tamping it around the roots. Repeat the planting process to plant individual strawberry starts every 8 to 12 inches along the entire spiraling row of the planter.
Water the soil in the spiral planter immediately after planting the strawberry starts. Apply 1 to 2 inches of water form a garden hose to each tier, moistening the soil to a depth of 12 to 24 inches.