Beautiful perennial borders and productive vegetable plots need more than sunshine, water and the right garden fertilizer; unlike native plants, they require good soil preparation and amendments to succeed. Garden plants are often non-native or hybrids; they are planted more closely and fertilized to encourage large flowers or good yields. Prepare soil and planting beds to improve soil texture, aeration and fertility.
Starting the Bed
Plants need beds free of competing weeds and located away from trees or shrubs with far-reaching shallow roots. Locate beds where they will get at least six to eight hours of sun each day. Prospective beds should be cultivated deeply with a rotary tiller or by hand; If the topsoil is thin, add soil to the bed to increase its depth to 8 to 12 inches. Topsoil should be turned several times to aerate it thoroughly. Raised beds are convenient for vegetable gardens or any bed that will require frequent attention as well as for older or physically-impaired gardeners.
Before adding anything to garden soils, gardeners should test their soil for pH and nutrients present. Basic test kits are available at garden centers and U.S. Department of Agriculture state extension offices provide complete instructions and supplies for homeowners to conduct inexpensive tests. A soil test will indicate whether amendments are needed to correct the garden soil. Extension agents are often good sources of information regarding corrective action for local soils.
Gardeners need to correct soil texture so water drains easily unless they are planning a wetland garden. Good soil structure allows air and water to get to plant roots and prevents erosion. Clay soils need additions of 2 to 3 inches of well-rotted compost and peat moss to open them up. Sandy or silty soils benefit from the addition of Compost, manure and peat moss. The Ohio State University recommends adding 3 to 4 inches of organic matter and 1 to 2 inches of coarse be added to garden soil. Drainage tile or a French drain--an underground channel of gravel--can be added to heavy subsoil to draw water away from gardens.
Many plants grow best in soil that has a slightly acidic pH: all need a dependable supply of macro and micronutrients. A soil test will tell how if and how much lime or sulfur should be applied to raise or lower pH--the number that tells the acid or base balance of a soil. Soil tests also identify trace elements that may be needed. Garden fertilizers containing nitrogen, potassium and phosphorus make good additions just before planting when they will be consumed by plants.
Mulch protects soil and cover crops protect cultivated soil until planting. Replace nitrogen loss with additional manure or fertilizer when using straw, wood chip and bark mulches. These carbon-heavy materials consume available nitrogen during their decomposition. Cover crops provide an alternative that contributes to soil fertility. They grow while cultivated beds lie fallow and are plowed under before planting, supplementing soil nitrogen levels.