|I have heard many arguments for and against adding organic material to topsoil in ornamental planting beds. In my area, the topsoil that is being sold is not true topsoil although it classifies as sandy loam. It tends to be void of or low in organic material.
If I'm bringing in a foot of this
|Organic matter is extremely benefical to plant roots and as long as you amend the entire planting bed rather than simply amending the planting hole, organic matter is an excellent way to loosen and aerate the soil and to provide trace minerals and nutrients to plant roots. The easiest way to incorporate organic matter is to spread 3-4 inches over the top of the planting bed and then work it in to a depth of 8-10 inches. After planting, spread another 2-3 inches over the top of the bed. You can renew this mulching material by digging it into the soil at the end of the growing season and placing new organic matter over the top of the bed. Organic mulch will help suppress weeds, moderate soil temperatures and slow water evaporation.
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