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GARDENING BASICS

FRUIT, VEGETABLES & HERBS

TREES, SHRUBS & VINES

LAWN & TURF

HERBACEOUS ORNAMENTALS

INSECTS, DISEASES & WEEDS

WILDLIFE IN THE GARDEN

PLANT YOUR LANDSCAPE

HOME:    GARDEN BASICS:  SOIL PREPARATION

Introduction Gardening Equipment: Tools for getting started Soil Preparation Composting Fertilization Use of Pesticides in the home landscape Organic Gardening Irrigation

The ideal garden soil is deep, friable, well-drained, and is high in organic matter. Proper soil preparation provides the basis for good seed germination and subsequent growth of plants. Managing soils for optimal plant growth is an ongoing process and consists of proper tillage, improvement through addition of amendments, fertilization, and irrigation. Soils in Idaho vary widely due to topography, climate, and origin. In southern Idaho, most soils are high in pH (alkaline) and have very little organic matter. These soils may need extra applications of phosphorus and micronutrient fertilizers and should never be amended with lime or wood ash. Northern Idaho soils can be relatively low in pH (acidic) and have considerable organic matter. Some of these soils may need pH adjusted upward with lime. In either location, soils can be variable in texture, from sand to clay. The pH of your soil is important in determining which nutrients will be readily available to your plants (see illustration at left). Sandy soils need constant addition of organic matter, frequent and light applications of water, and constant fertilization. Clay soils may need to be amended with organic matter and/or soil additions to improve water penetration. It is important to know the characteristics of your soil in order to design an appropriate management plan. Regardless of soil type, careful use of various amendments can improve soil and provide the best possible starting situation for your plants. The best amendments provide organic matter and consist of manures, composts, peat moss, crop residues, grass clippings, green manures, bark, wood chips, straw, or any number of other materials. The type of amendment chosen is dictated by availability and cost. Before fertilizing or tilling, it is best to get the soil tested for nutrients, pH, and organic matter. There are simple soil test kits available at nurseries that can do an adequate job. There are also several labs, both university and private, that will be happy to test your soil for a fee. Once you determine fertilizer needs, broadcast evenly on the soil surface and till it in. Make sure the soil is not too wet during cultivation to avoid compaction. It is important to understand that most plants needs are supplied by the soil. Consequently, proper soil preparation will go a long way toward achieving a successful garden. For more information on soil preparation, see a brief, but excellent Utah State University publication, at: extension.usu.edu/files/gardpubs/hfs01.pdf. This Virginia Tech publication provides good information on soil amendments: www.ext.vt.edu/pubs/envirohort/426-313/426-313.html. Washington State University provides a comprehensive guide to soil management, at: gardening.wsu.edu/library/lanb003/lanb003.htm top