The rule of thumb for harvesting onions is to dig them when the tops have fallen over. However as long as the tops are green, the bulbs will continue to plump up. So when is the ideal time to harvest them. That partly depends on the weather, as do so many things in the garden.
If you’re having a rainy season, onions can re-sprout, even after most of the tops have started turning brown. That may sound like a good thing, but re-sprouting will shorten their storage life.
Of course, that doesn’t really matter if your growing a variety that doesn’t store well to begin with, like a Sweet Spanish. But if you’re growing a lot of onions to keep throughout the winter, don’t wait for the tops to brown. Get them out of the ground when the leaves have fallen over.
H3 – Hot, Hazy, and Humid
Even in good years, my garden has more than its share of humid days. And just like every other vegetable in the garden, onions can experience disease problems brought on by too much humidity. So even without a lot of rainfall, I’ll be sticking with the Tops Down, Dig Up mantra. The little bit of plumping they might do if I left them to go completely brown isn’t worth the risk.
Once They’re Up
Finding a warm, dry place to cure them for a couple of weeks can take some detective work. Someone recently suggested I put a screen across a wheelbarrow or wagon so I can move them in and out of the garage. That’s what I’ve done with seedlings when I harden them off, but I never thought to try with onions or garlic. Thanks for the idea,d “gladtogarden”.