Onions on the bolt
by Johanna Silver, Sunset test garden coordinator
Most of the crops are coming along just fine – the tomatoes are bursting out of their cages and the melons are sprawling and tangling in delight. The onions, however, have seen better days. My predecessor, Ryan, planted Spanish Whites last fall. By the time I started in mid-April they looked, well, sad. They weren’t getting bigger and many were bolting – trying to produce a flower. We wondered if something went awry with watering or temperature. We wondered if we mistakenly planted a different variety that doesn’t overwinter. We scratched our heads and wondered up all types of possible causes.
Many finally bulbed up and are looking fantastic, meaning that we probably did plant the right variety. Still, about half of them didn’t make it. I cut off the flower stalk in hopes of sending the energy back down to the bulb, but they were intent on bolting and continued sending up a thick stem:
What did I learn? Try as best you can to keep your irrigation regular and hope that your onions don’t endure rapid fluctuations of warm and cold temperatures in the spring. Wise gardeners tell me that it’s nearly impossible to stop the bolting once it’s started. I should have pulled them out of the ground earlier and just used the smaller bulbs in the kitchen, but I kept my fingers crossed and left them in the ground. Silly me, the bulbs not only failed to form, they rotted.