Along with tomatoes, I love my onions. Onions for everything: soups & stews, sauces, salads, eggs & quiches, you name it. The onions I had grown in our previous garden all did well. I had no reason to believe they would not do well here at 9,000 feet. I’d read on a local county resource list that other gardeners had success with some of the same varieties I’d grown before, and I still had some seeds, so I tried those. I expected success in my high-altitude garden. Well…the leeks and scallions did well, but the bulb onions did not. I planted around 40-50 of them. Dang.
I always start my onions from seed, and have always had good success with this method. I started them all 10 weeks prior to the last frost date, and expected to be able to plant them outside at that time or a bit sooner. These were all started in soil blocks, and I ended up transplanting them outside at about 7 weeks after starting, I had intended to keep them inside under lights the full 10 weeks, but the weather had been so nice, I planted them out, kept them covered at night, and I thought they would do fine. No. Too cold? Too soon? They didn’t die, but did the colder weather stunt their growth? By the end of the season, a few of them had bulbs that were maybe 3″ across. The rest were smaller, some with no bulbs. The stalks never really fell over. I ended up bending them over myself. I kept them mulched well and in the garden until finally, in October, before it seriously froze (but after several nights below 32), I pulled them all out of the ground to cure on racks in the greenhouse. Very few of them cured as usual–the tops never dried up. The thick stalks remained green and some continued to grow. I was able to cook with them–since they were so small it didn’t take long to use them up before they spoiled. Unfortunately, I somehow lost a lot of photos taken near harvest time. The photo above was taken earlier in the season.
As I mentioned earlier, the leeks and scallions all did well. I was very glad to have them! I used the leeks until I was afraid they might go rotten, and before they did I froze the remainder. I still have those ready to make a soup or something. Most of the scallions I planted were “Evergreen Hardy”, a multiplier onion. I left most of them in the ground all season, and they really multiplied! I ended up with too many all at once. I’ve left some of those in the ground, well mulched, to see if they will survive the winter.
Some thoughts about day length. This can be a bit confusing. The best “day length” here for onions is apparently “Intermediate Day.” We are at latitude 38.77. Some sources suggest that we can successfully grow either Intermediate-Day or Long-Day onions. Our former location in Wellington was latitude 40.73, where I grew both long-day and intermediate-day onions. According to Dixondale Farms, all of Colorado should be growing intermediate-day onions, and suggests that both daylength and temperature trigger the transfer of forming leaves to bulbing. Garden.org suggests that anywhere above latitude 35 degrees should grow long-day onions, and that “day neutral” or “intermediate day” onions are bred to be less sensitive to day length. Other sources suggest that anything north of either the 37th or 38th parallel should be “long day”. So, it’s a bit confusing, but for the most part, I’ll try to stick with “Intermediate Day” varieties.
I planted 35 of the variety, “Clear Dawn”, from Fedco Seeds. They indicate that these are a “Long Day” variety, for latitudes 37 degrees and north. These were a substitute for the “Copra” I’d previously had good success with but were hard to find this year. These were the most successful of the onions I did this year. The others I did were a few each of: Southport White Globe, Sedona F1, and Red Torpedo, along with some Zebrune shallots. Here are the results: