For over thirty years I grew onions from sets, just as my grandmother and mother had. White ones for using over the summer and early fall; yellow ones for storage. I never saw red ones until I went to college. Then I traveled to Italy and discovered cipollini, those luscious, small, flat heirloom gems that are so sweet they caramelize when grilled or roasted. And marinated cipollini are a gourmet delight for appetizer trays or chopped for muffullata, that traditional New Orleans olive-salad stuffed sandwich. Frustrated that I couldn’t find them here, I ordered seeds from Pinetree, a variety called “Bianca di Maggio.”
Growing onions from seed was new to me, but I figured “Hey! Chives are their cousins, and they grow from seeds like weeds, so it can’t be that hard.” However, just to be on the safe side, I consulted my go-to bible, Nancy Bubel’s “The New Seed-Starters Handbook,” which I’ve had since 1988. Yes, I know you can find seed-starting advice on the web, but I just feel more comfortable getting my info from someone I trust. After all, seeds are not cheap and space is limited so I don’t want to waste either, not to mention time. It was from Nancy’s book that I learned most onions take a long time to grow before they are ready for the garden. Here in Indiana (Zone 5) long-term varieties need to be seeded in early February. That suits me just fine, because by February I’m itching to start something…anything! I’ve found that for my potager all full-sized onions need to be sown by Valentine’s Day, so I’ll be seeding the final “regular” onions today.
Bubel advises that onion seeds vary in the time they take to germinate, even from the same seed packet and that fresh seed is necessary because onion seed has a short shelf life. And if they aren’t stored in a cool, dry, dark place that life can be even shorter. In the photo above it’s easy to see that one seedling is well on its way, one above it is half its size, and one to the right is just emerging. Three up, 97 to show yet. Onion seeds germinate best at 65-80 degrees F but as soon as there are green shoots, grow them on a bit cooler, no higher than 70 degrees during the day and 50 degrees at night. I sow them in rows in a flat, then prick each one into a 4-pack when they are 2-3″ tall. When they are well-rooted and danger of hard freeze has passed, I harden them off a day or two to accustom their little grassy leaves to wind.
While waiting for those seeds to grow into “grass” analyze and prepare the soil for transplanting into the garden or containers. (Cipollini grow great in a window box along a patio edge.) Onions prefer a “sweet” soil (that is, not acidic so check the Ph…6.5 is good) and if soil is deficient in potassium, they won’t keep well no matter what variety is planted. Low phosphorous levels will cause thick necks and slow maturity. Gypsum fertilizers or soil conditioners or sulphur will prevent onions from being sweet. Very high nitrogen will often hinder good-sized bulb formation, but the biggest factor is warmth. Onions are day-length sensitive. Most onions need long, warm days and short nights to bulk up into a bulb. Lots of sunshine is a must so choose a full sun location. Don’t let all that info scare you. The sunshine, warmth and average soil will usually work fine, but a soil test can remove any doubt. Cipollini are small members of the onion family (only about 1″ tall and 1-3″ across) and are easier than a big Walla-Walla (which require over 110 days of heat) because they mature quickly. If you’ve never grown onions, start with bunching onions, scallions, or cipollini to build your confidence. (And if you live in the South, choose “short-day” full-sized onion varieties, rather than the long-day ones I grow. However, cipollini don’t really seem to mind where they grow.) When they are ready to transplant into the garden or windowbox, dig a trench the width and depth of the 4-pack soil cube, sprinkle a bit of compost in the bottom and plant the cubes of soil cheek to jowl, trying not to disturb the roots as you set them in. Rows can be place adjacent to one another. (For larger varieties of onions, the soil cubes and rows must be spaced further apart to allow ample room for full-sized bulbs.) Lightly bring soil over the edges to fill in the trench and prop up each little green blade, and that’s it. Keep them weed free, and you’ll have beautiful cipollini in about 8 weeks, depending upon weather. When the tops fall over, they are ready to harvest. I do a large planting, replacing peas, so there are enough to marinate and can (shown below) for the entire winter. (The balsamic vinegar, rosemary and onion-flavored broth left when the can is empty makes a terrific marinade or salad dressing ingredient, so don’t waste it!) For succession crops, to ensure there will always be cipollini to grill with veggies or steaks, I plant them every two weeks throughout the summer, making small trenches here and there whenever another crop of lettuce, spinach, carrots, etc. comes out. This method works for any small onion, scallions, pearl onions, or bunching onions. It’s not the only method for growing onions, but it has worked well for me. And I have to admit, last year I went to France and left a flat of 4-packs on the bench for weeks. They never did get planted into the garden, but matured nicely in the flat and went right to the grill! As I said, cipollini are very easy!
Once I realized how easy cipollini were, I expanded my selections to include “Red Marble” and “Gold Coin” cipollini for storing and winter grilling. I like “Bianco di Maggio” the best, but they don’t store well which is why I can them. Also added are these delicious “Red Long of Tropea,” another onion I met in Italy that I adore, as well as “Bassano,” a big round red Italian onion and “Flat of Italy,” which is a really good keeper for me. I can’t find any of these in stores or markets, so I’m delighted to be able to grow my own. This year, I’m adding “Patterson,” a large, yellow F1 hybrid that stores exceptionally well. With all the shallots and garlic, chives, garlic chives, and walking onions there’s quite a selection of tasty alliums in the potager all season, and braided onions, shallots, and garlic hanging on the allium rack in my garage all winter. (Photo is before garlics and most onions were added.)
So, if like me, your are itching to start something, seed some onions. This summer, you’ll be crying with joy as you harvest!