Soil Preparation
Amendments
& Fertilizers

     Preparing the garden soil for planting is crucial for success.  Plan to work the soil 2 - 6 weeks prior to planting to maximize the benefits of amendments and fertilizers.  Consistent attention to healthy soil will produce the best results in San Diego soils.

• too wet - if soil sticks to shovel, wait to work.
• too dry - if soil is dry and powdery, water deeply and wait 2 - 4 days.

• remove large rocks and debris.
• work in middle of day if possible to avoid cutting earthworms.
• rototill and/or spade to a depth of 8 - 12 inches, break up clods, rake smooth.
• optional - consider using "double-" or "single-digging" techniques for improved loosening and conditioning of soil.

• improve physical condition or structure of soil (aeration, drainage).
• organic:  dead plant or animal materials (manure, compost).
• inorganic:  mineral materials (gypsum, vermiculite, perlite).
• for clay soils, gypsum and organic matter help break up soil and increase drainage.
• for sandy soils, organic matter helps improve water and nutrient holding properties of soil.

• supply essential elements to plants for growth.
• organic:  dead plant or animal materials (manure, bonemeal).
• inorganic:  chemical or mineral materials. Commercial products list nutrients as a ratio of nitrogen (N), phosphorus (P), and potassium (K), respectively.

• obtain a soil sample to most accurately determine soil needs and fertilizing schedule. Contact Master Gardeners for assistance.
• ORGANIC MATERIALS ARE THE BEST WAY TO IMPROVE SAN DIEGO COUNTY SOILS.
• amendments/fertilizers should be free of weed seeds, toxic materials, and disease organisms.
• if used, fresh manures and other uncomposted materials should be spread evenly in thin layer and worked 6 - 8 inches deep, 4 - 6 weeks prior to planting to prevent plant injury.
• other organic materials can be spread 2 - 4 inches thick and worked into the soil 6 - 8 inches deep, 2 - 4 weeks prior to planting.
• commercial fertilizers can be used alone or in combination with manures and compost. Ask vendor for assistance in selection and follow label directions.
• additional applications of fertilizer containing nitrogen may be needed during plant growth. Apply small amounts of nitrogen fertilizer and water immediately to avoid plant "burning."