Proper soil preparation not only ensures your flowerbed will perform at its best, but also makes planting in freshly worked soil a true joy.
TIP: Our expert gardening advisor, Karen Thurber adds, "Always start by having a soil test done. Local county or state agricultural extension services provide reliable soil testing with amendment recommendations."
Step 1 - Assess the Soil
Good flower bed soil is a dark brown color with a loose texture. Poor quality soils are typically pale or yellowish in color. Clay-like soils are gummy, heavy, dense and can be difficult to work with. Sandy soil is very porous, allowing nutrients to wash away easily. Organic amendments improve both clay and sandy soils and add nutrients to all soils.
Step 2 - Buy the Right Amount of Amendments
Measure your bed and figure the square feet (width times length). Plan to add about 2 to 4 inches of amendments to good soil. Add 4 to 6 inches if soil is poor. Amendments in bags have product quantity information printed on the bag, based on your square footage. Bulk products are sold in cubic yards. A cubic yard is 27 cubic feet, 3 feet x 3 feet x 3 feet.
Step 3 - Add the Amendments
If your soil looks fairly dark and breaks apart into soft clumps, you can add amendments immediately. If your soil is clay-like or sandy, remove about 3 to 4 inches of soil. Place it on a tarp for less mess. If the soil that is now exposed is of poorer quality than the soil you just removed, remove another 3 to 4 inches and discard. Add back the topsoil you reserved. Work the amendments in with a shovel or spade. Remember to match the size of your shovel or spade to your strength.
TIP: Karen suggests, "If removing and replacing the soil is unfeasible due to cost, or the size of the garden; the regular application of organic matter over time will improve your soil."
If your soil is heavy clay, break up large clumps. Discard any roots, rocks or debris. Add 1 to 2 inches of sphagnum peat moss to the bed. Turn the soil over to incorporate well. Add 1 to 2 inches of compost, turning soil over. Add 1 to 2 inches of top soil or a blended mix, turning soil over once or twice. You are ready to plant when the soil falls easily off the shovel. Remember not to add sand to heavy clay soil. It will become hard and unworkable.
Step 4 - Adjust the New Soil Level
Adding amendments increases the volume of your soil. If the bed is next to a sidewalk or driveway, the soil level should be slightly lower than the hard surface. If you are adding mulch after planting, lower the soil level by another inch or 2. Remove unneeded soil to a garden cart, wheelbarrow or tarp. Use the extra, now improved, soil to fill containers or raised planters, or add to other beds in your garden. For beds inside or bordering a lawn area, rake the extra dirt toward the bed's interior. This will improve drainage and discourage grass from growing into the bed.