Greensand is often used by organic gardeners as a natural source of potassium. It is available as a sand or sediment type amendment for your soil that can be added as part of the soil prepartion before planting or added later as a top dressing. It comes in various formulations based on the amount of sand, etc. that is mixed in, you can find it as diluted as 0-0-0.1, but it has many trace elements as well.
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Filed under Organic Gardening by John
