Onions not bulbing
I planted out red onion plants 4/5 months ago. They have developed huge leaves, but seem to be reluctant to form into bulbs. One is bolting. I live in NZ on the Coromandel Peninsula in the North Island. Our winters are mild and wet. Please advise.
Certified GKH Gardening Expert
This is an issue caused by a lack of phosphorus in the soil. It may be too late to reverse these onions (but it does not hurt to try), but add bone meal to the soil to increase phosphorus. At the very least, this will help fix the soil for future plantings. Also, have the soil tested to see how severe the deficiency is.