06/19/2026
I grew radishes and onions from scraps in my Glendora garden, but they bolted. Here is what I learned: When vegetables "bolt," they prematurely shoot up a tall flower stalk to produce seeds, which diverts energy away from growing the root or bulb. In California's climate, this is primarily caused by warm spring/summer temperatures, sudden weather shifts, or long daylight hours. Why They Bolted: Warm Weather: Both onions and radishes are cool-season crops. When temperatures rise (especially getting into the 70s and 80s), the plants panic and rush to reproduce.Regrown Sprouts: Growing vegetables from kitchen scraps inherently carries a high risk of bolting. Because the plant is regrowing from a mature base rather than fresh seed, it is hardwired to finish its life cycle by flowering.What You Can Do NowRadishes: The root is likely woody and bitter. However, bolted radishes produce highly edible, spicy seed pods (often called "radish tails") that taste like spicy snap peas or radishes. You can eat these raw in salads or stir-fries. Onions: The original bulb will become woody, but you can still harvest and use the green stalks (scapes) as scallions. If you let them flower, you can also collect the seeds for next season.Tips for Next Time in CaliforniaPlant in Fall or Winter: To avoid the heat, plant root vegetables in the fall (September–November) or late winter (February) so they mature before the hot California summer hits.Grow from Seed: While regrowing scraps is fun, you will get much better, more uniform root and bulb development by growing radishes and onions from seed rather than sprouted kitchen scraps.
