Nutrients contents of worm casting (roughly)

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The content depends on the worm's diet or the food that they ate. "Analysis of earthworm castings reveals that they are richer in plant nutrients than the soil, about three times more calcium and several times more nitrogen, phosporous and potassium" (K.P. Barley, Advances in Agronomy, Vol. 13, 1961, p. 251) Usually plain worm casting made from variety of organic waste will support plant growth without additional nutrients for some weeks (3 to 5 weeks), although my experience is nitrogen and magnesium supplement does not hurt (with a N and Mg greedy plants) The worms will consume nutrients from the waste, naturally, into their bodies. This is not lost however, as the worms themselves make an excellent fertilizer (NPK 10-1-1 with high calcium and magnesium) Worm casting NPK numbers found on sale in the internet ranging from NPK 3-2-2 to 0.5-0.1-0.1. Worm casting also usually contain high levels of other macronutrients and micronutrients and while the three main nutrients levels may appear low, there is usually plenty of micronutrients in worm castings and general nutrients availability is high. But again this depends on what the worms ate.