Rock-hard clumps of soil are inhospitable to both seeds and the roots of transplants, leaving you with a poor harvest of anything but the most determined weeds. The best garden soil is smooth, rich in organic matter and able to absorb water well without holding puddles. Cultivating and amending soil prior to planting eliminates clumps and improves soil structure when done properly and at the correct time.
Dig 6 inches into the area where soil is clumped in early spring. Grab one handful of the soil. Squeeze it in your hand to form a ball of soil. Drop the ball of soil from waist height. If it shatters easily, the soil is dry enough to work the soil to loosen its clumps. If it does not shatter easily, wait. Working soil when it is wet creates even more clumps.
Spread a 2- to 6-inch layer of finished compost or composted manure over the entire clumped area with a rigid garden rake. The addition of such organic material is one of the most effective ways to improve soil, particularly clay soil, which is the type most likely to form unwieldy surface clumps. As organic material breaks down, it helps tiny clay particles stick together to form larger aggregates -- actually microscopic clumps -- with spaces between them to allow for the water and air movement that prevents large clumps and crusting.
Dig a hole at one end of your planting area, making the hole about 16 inches square and the depth of the blade of your shovel. Deposit the soil from that hole at the opposite end of the planting area.
Stick the tines of a garden fork into the soil in the bottom of the hole, stepping on the back or top of the fork to force it into the compacted soil as deep as possible. Rock the garden fork's handle back and forth, loosening the soil. Repeat the procedure across the bottom of the hole.
Move to the space immediately behind the hole, and dig into the layer of finished compost or composted manure and soil. Deposit it in the hole you just dug, breaking up clods with the blade of your shovel as you place it in the hole.
Repeat the hole-filling and hole-digging tasks until the finished compost or composted manure is incorporated into the entire planting area. Place the soil you removed to create the first hole into the last hole to finish the procedure.
Rake the area's surface with the rigid garden rake, pulverizing all remaining clumps with the rake's tines and making the soil smooth.
Spread mulch onto bare soil after planting to prevent crusting as the soil dries.
Incorporate a 2- to 3-inch layer of finished compost or composted manure into the planting area each year in the same way until the soil is consistently clump-free.
Things You Will Need
- Finished compost or composted manure
- Rigid garden rake
- Measuring tape
- Garden fork
- Avoid creating clods by not working soil when it is wet.
- A rototiller can be used but presents the danger of overworking the soil, disturbing worms and other insects that aerate soil, and forming a hard layer of compacted soil just below the depth of the machine's rotating tines.
- University of Florida IFAS Extension: Soil Compaction in the Urban Landscape
- Ohio State University Department of Horticulture and Crop Science: Plant Facts -- What's the Best Way to Break Up Clay Soil in My Garden Beds?
- The Samuel Roberts Noble Foundation: What Does Organic Matter Do in Soil?
- Ohio State University Extension: Intensive Organic Gardening
- Alabama Cooperative Extension System: Use Tiller Sparingly When Preparing Soil
- Hemera Technologies/AbleStock.com/Getty Images