The Skinny on Onions
I bought a bag of 80 onion sets (little bulbs up to 3/4" across) at a big box store last fall. For $1.49 I figured it was a good bet. I hadn't done my homework and didn't know what to look for. In October I planted two rows for green onions, where the sets were spaced less than an inch apart and 2 inches deep. Then I planted one row for table onions where the sets were spaced 3 inches apart and just below the surface.
These instructions, provided on the package, worked well. For months, I picked the outside leaves of the green onion rows to use in salads and cooking. At the end of April, I started pulling up the green onions, one-by-one as needed. I finally got to the table onion row in the middle of June and continued to pull onions one-by-one as needed. I hadn't harvested any of their leaves, because they needed all their sugar produced by photosynthesis to build their bulbs. Most of the sets in this row did produce two to three-inch bulbs, but a few did not. The leaves are more pungent this late in the season and some of the leaves have now completely withered. This is when you're supposed to pull out the onions, braid what's left of their leaves, and hang them on a rafter to dry out. I don't have many left by now, so I'll continue to work my way through the rest of the row and plan better for next year. There was a lot I didn't know.
Long-Day and Short-Day Onions
The bulbing onions (Allium
cepa) fit into three categories:
2)Intermediate-day (or day-neutral): These varieties that need 12 to 14 hours of daylight to start producing a bulb.
3) Long-day: These varieties require 14-16 hours of daylight to form onion bulbs. These are good for more northerly areas where the summer days are much longer and where the bulbs can't be left in the ground over the winter.
When it gets hot (like now), any of these varieties will stop growing--if I'd left mine in the ground, they'd start to grow again in the fall and produce a flower. I still have the label from my onions, so I was curious what kind I'd lucked into. There's no indication: The label says, "Onion Bulbs (Yellow)". The fine print on the back says they came from Arcadia, FL. So that was hopeful--I've learned that bulbs from Holland or Holland, MI may not do well here. Upon doing some more research I found that onion sets are produced only for short-day onions. So by dumb luck, I planted the right type of bulb and the positive results prove that out. This fall, I plan to be better organized about my onions and will plant onions sequentially once a month or so during the winter so that our harvest might be a little more spread out.
Variety is the Spice of Life
Today there are hundreds of onion cultivars, differing in day-length requirement, skin color (white, brown, yellow, red, or purple), size, shape (globe-shaped, flattened, or spindle-shaped), pungency and sweetness. The chemical characteristics of the soil determine much of the pungency and sweetness of the crop. Some short-day cultivars are Excel, Yellow Bermuda, Granex, and Texas Grano, White Granex, and Tropicana Red.
Vidalia onions are sweet, non-pungent short-day onions, usually Granex or Texas Grano that are grown near the town of Vidalia, GA. Onion farmers there have purchased the exclusive right to use that name.
Bunching onions (A. fistulosum)
are non-bulbaceous perennials that you can keep going with that
mathematical oxymoron--multiply by dividing. When you need
some onions, dig up a bunch, but leave some in the ground, so new
bunches can form. Bury them two or three inches deep if you
want the stems to be white. Spring onions or green onions,
immature bulbing onions, are often used in place of the true bunching
onions. This how I used my two rows of green onions and I'll
probably do that again, but I'm going to try some true bunching
onions next year, too. I'll let you know how they do.
Ginny Stibolt would like to hear from readers who have suggestions and questions. After all, there are more than a few transplanted gardeners here in northeast Florida trying to figure out what works and what doesn't in planting zone 8/9. She's in the process of writing a book, "Sustainable Gardening for Florida," to be published by University Press of Florida.