Sandy soils are easy to work but have low water holding capacities, so plants may suffer from moisture stress in hot weather. Nutrients may be lost as irrigation water moves downward through the soil.

Plants Indigenious to Location- Picking plants that thrive in sandy soil conditions and are indigenous to your locale should be a consideration when planning a garden. Sandy soils can be improved to some degree but in general it is difficult to change the soil type. 

Importing Soil- A method that is often used but may not be affective is hauling in soil. In most instances you are better off to work with the soils that you have. You know what their problems are. Hauled in soil may not be any better than that in your yard.

It could be a source of noxious weeds that you don’t have. If you need to cover a rock or coarse gravel bed or raise the level of a yard area, fill may be needed. It may or may not improve an area in which you wish to grow plants.
 

Building Soil Structure- Adding organic matter is a much more affective method of improving sandy soil structure. Nutrient and water holding qualities of sandy soils can be increased. As the organic matter breaks down, its components continue to have soil improving characteristics.
 

Begin by incorporating 2 to 3 in. (5-8 cm) of organic matter 6 to 8 in/(15 to 20cm) deep. This application will not last forever and you should plan to add about 2in.(5cm) more each year  Summer mulching, compost or ARBICO Organic Compost Plus addition will be helpful.

A lot of organic material may be needed to do the job so look for abundant, inexpensive materials. Leaves from deciduous trees may be gathered in the fall for composting and/or soil incorporation. Needles from conifer trees may also be used. Bark, sawdust, shavings, and other wood products are less likely to contain weed seeds than are manures. Peatmoss is an excellent material, high in organic matter and somewhat acidic.

Cost- is a major factor for the quantities needed. Manure may be available and is an excellent source of organic matter. If properly handled, it may contain substantial nutrients when used in sufficient quantities

Large quantities of mature, woody type products such as sawdust, bark, leaves, and straw will promote nitrogen deficiency in plants because of their high carbon content. Overcome this problem by adding a nitrogen fertilizer when incorporating them into sandy soils.