Q: My first attempt at growing turnips, beets and carrots resulted in mainly leaf growth. Should I have applied 5-10-10 instead of 10-10-10?
A: Excess nitrogen would indeed cause lots of leaves and few roots. I don’t often see the low-nitrogen 5 10 15 fertilizer but you can mix your own. All you need is the following: ammonium nitrate (34 0 0), triple superphosphate (0 46 0) and muriate of potash (0 0 60). Most nurseries have all three.
In a plastic tub, mix a half pound of ammonium nitrate with one pound each of the superphosphate and the potash. The result is a fertilizer with a nutrient analysis of 7 18 24. Notice that the ratio between the three nutrients is close to 1:2:3, and that is the same nutrient ratio as 5 10 15 fertilizer.
Plant ryegrass on your garden now and use the 7-18-24 on your root crops next fall.