Q. I have been reading that phosphorus promotes root growth. Would that mean that by adding a little extra phosphorus, one could increase the yield of root vegetables?
A. Plants use a certain amount of phosphorus for optimum growth. That amount is usually about 1/2 as much as the amounts of nitrogen and potassium, and that’s why the Mittleider Weekly Feed formula has NPK in approximately a 2-1-2 ratio, and the formula is sufficient for all root crops, without adjustment.
Adding extra phosphorus to your garden, beyond that contained in Mittleider Magic Weekly Feed, will not improve your yields, but might actually upset the balance, and cause other elements to show problems.