||Benefits / Cautions
|Wood sawdust, shavings, or ground bark
||Nitrogen should always be added with these amendments. Add ammonium sulfate, blood meal, or cottonseed meal to provide extra nitrogen. Do not use chemically treated wood or sawdust in the garden.
||Good for high bacteria count.
Bad because of high salt content. Can also have an abundance of weed seed unless composted. Ammonia gas from fresh manure can damage plants. Use only when well aged or composted.
||When added to a moderately alkaline soil will pull pH down toward acidic. Loosens and aerates soil.
Will last up to five years in soil. High water holding capacity.
||Not a practical amendment for clay soil. Would need to add large volume of sand to clay which is expensive and difficult to mix. Adding a small amount to clay will only increase density and may create concrete.
||Makes soil more acidic. Process occurs slowly and takes up to a year. Mix small amounts into soil. Heavy application can damage plants. Bacteria change Sulfur into acid
|Gypsum (Calcium Sulfate)
||Used to reclaim soils that contain excess sodium. Does not change soil PH. Mix into soil and water thoroughly several times.
||Light weight, fluffy, clay product. Used in potting soil. Holds several times its weight in water and allows room for roots to grow.
||Light weight puffed sand product. Provides aeration and drainage.