The Special Problem of growing bulbing onions Indoors.

And…the frustrated invention of Bulbless-Onion Bulgur Balls.

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When I first started this blog back in March, I was just looking for a way to get my mind off the ‘Rona. Now it’s August, and I no longer take my temperature twice a day. I have stopped reading about the Spanish Flu of 1918. And 6 months into this blog I realize I have grown to love writing and researching about plants. Maybe I should have become a plant doctor instead of a human doctor. Plus, plants don’t cough all over you.

I have especially enjoyed getting to share what I’ve learned over the years about gardening indoors. Because it is kind of a weird field of study. A bit of a niche. Maybe one day I will formalize my knowledge into a book and become a pillar in the field of bathroom gardening.

I appreciate every success…

You know that scene in Castaway, when Tom Hanks says, “I have made fire!!”? Well, I kind of feel like that every time a plant grows in my artificial environment. I don’t beat my chest like he did, that would be excessive. But I do get pretty excited. When those plants actually form vegetables, and those vegetables actually taste like what they’re supposed to, I can’t help but feel like this is something extraordinary. And then I wonder why everyone isn’t growing peas and cucumbers in their bathrooms! I’m just waiting for it to catch on…

Take this beet, for example, that grew from seed to harvest completely indoors.

It survived the seedling stage. Win! It grew foliage. Fantastic! And then for some reason, it decided to form an actual beet at the base! Huzzah!! The color was deep red and the taste was full of flavor. It made an elegant, summery, roasted beet salad. We even used some of the tops for greens. I mean, how cool is that?

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And learn from every failure…

Onions, on the other hand, have been a frustrating challenge.

Why don’t they do what the beet does and make a nice little bulb at the bottom? Green onions, chives and leeks seem to do well in my little indoor garden. I even grew pretty purple alliums back when I was growing just flowers. It’s the bulb of the onion that’s the problem. At my best attempt, I got this:

It tasted really nice, so it wasn’t a total flop. But it was supposed to be a NY Early yellow bulbed onion. This guy just looked rather pathetic and unformed.

And on this particular subject, the literature is no help. There is a remarkable lack of information about growing onions in your bathroom.

I want to be able to look up the “Best Onion Variety to Grow in Your Indoor Garden” and get the answer I’m looking for. But what I typically find is stuff like “How to Re-grow an Onion from an Onion Scrap”, or “How to Grow some Casual Green Onions or Chives on a Window Sill”. I threw in the word casual to show my disdain. I shouldn’t be so judgmental, but this is just not what I am looking for.

Don’t get me wrong, those certainly sound like fun things to do. And I probably will try both of them, now that I’m thinking about it.

But what I really want, is to grow a big, fat, globe of an onion in my Tub Garden. From seed. And believe me, I will find a way to do it. If there’s one thing I learned in medical school, it was patience and perseverance. That’s two things obviously but you get the idea.

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The Importance of Day-Length

When I first started this whole indoor gardening fiasco, I actually thought the day-length cycle would be more of a problem. The reading I did said that fruits, flowers and vegetables wouldn’t bud or make flowers until certain cues happened from nature. So I wasn’t sure if anything was going to do anything other than grow leaves, and then just plop over and die.

For example, in marijuana literature (because that seemed like the only information out there at the time) you set the lights to 18 -24 hours a day, (with preferably a blue spectrum) to encourage lush vegetation. Then, when it’s big enough, you convince the plant that winter is coming by turning the lights down to 12 hours a day (with a more reddish light). The plant gets ready for the cold to come and this “triggers” it to set it’s fruit (or buds in the case of the marijuana).

But there was no way I was going to start changing light cycles, or have red and blue light zones, and move plants from zone to zone like professional growers must do. I am just way to busy (lazy) for that. I figured I would only try this crazy experiment if I could do it very simply: White LED lights. All set on one timer. All in one room. Done.

I muddled my way through the first few years, taking notes and experimenting. I gradually increased my total light time to 16 hours a day (with 8 hours of total darkness) and found that this really was the sweet spot for my garden. Any longer, and the plants started to show signs of stress. Any less light, and they wouldn’t grow as big and robust. Fruits have been blooming, vegetables have been vegetating, and flowers have grown tall ever since, rather than short and stubby like they did at the lower light-cycle lengths.

So, overall, I was feeling like the day-length problem, and even the temperature cycles of actual nature, weren’t going to be much of an issue for my indoor garden. I felt like I had Mother Nature’s number.

Until I tried to get dumb onions to bulb.

Why onions are a little bit “more special”

So what’s the deal with onions? Well, they are pretty sensitive little vegetables. Occasionally, authors will throw out the term photo thermoperiodic when describing onions. As in, “These dumb onions are so photo thermoperiodic!” The term just means that onions are sensitive to periods of light and temperature.

I think, technically, all plants are photo thermoperiodic, but this word is specifically applied to onions because they rely on the effects of these seasonal changes to cue their bulb formation. Aha!

As many gardeners know, onions are divided into long-day onions, intermediate-day onions, and short-day onions. Usually, you can just go buy whatever type of onions are sold in your area and they will be fine for your latitude. For example, if you live way up north and your summer days are really long, you should plant long-day onions, and that is what you will find for sale at the stores near you. If you live down south closer to the equator, the short day onions will work, and that’s what they’ll be selling at your nurseries. You shouldn’t have to think too much about it.

Planted happily outside in nature, as most normal gardeners would do, an onion will spend most of the cooler spring months growing a healthy leaf and root system. Then, when the longest and warmest days of summer are approaching, a certain amount of these longer, warmer days will cause a hormonal change that causes the onion to stop putting energy into its leaves. Instead, it will direct it’s efforts into making a bulb. Each variety of onion has a different requirement for how many days, and how many hours, of light it needs to trigger that response. Then, as the days get shorter and cooler as fall approaches, the onion leaves will topple over – signifying that all of the plant’s energy is in the bulb, and it’s done for the year.

But what would happen if every day was the same length, and the same temperature. Every day, all year?

This is what I have observed in my own, ever-constant garden. The onions start growing happily. They make leaves and look healthy. But the perfectly constant environment, forever, means nothing else happens. They just go on, making leaves and roots. The onions must think they are stuck in early spring, in some place with extraordinarily long days. Nothing “triggers” them, and so they never make bulbs. I initially thought, with my garden getting 16 hours of light a day, I would be able to grow all three types of onions. But now, I am thinking it is the change in day length and temperature, not the absolute amount of lighted time, that must trigger the bulbing process.

I am going to try this experiment one more time with all three types of onions (long, short and intermediate-day) to be sure. If nothing bulbs, my theory will be proved and I may have to start playing with my light timers. Or my thermostat. Something I never really wanted to do. Something I may not really be willing to do…

The other kind of annoying thing about onions, is they take quite some time to grow. Their typical time to harvest is about 100 days, with some varieties taking even longer than that. So, they take up a lot of precious gardening space for a long time.

To put this into perspective, I planted this experimental set in mid July. Since the Pumba onions can take 155 days to harvest, they won’t be expected to harvest until at least mid-December!! This is truly a game of patience and perseverance. Which, as as I said earlier, are two things I luckily have.

Phew, these onions better taste amazing.

To pass the time, may I recommend Growing an Onion from a Kitchen Scrap? Or Growing Some Nice Green Onions or Chives, Casually, on a Window Sill with me? They will probably do very well and not require nearly this level of head-scratching.

Then, in December, with diligence and methodical observation, we hopefully will be able to move the science of Bathroom Gardening forward, one slow step at a time. And maybe I’ll get an onion to bulb indoors. If that does happen, I probably will do the Tom Hanks fire dance. And maybe even beat my chest, just a little bit, if no one is looking.

But wait! Before you leave, here is a fun (not frustrated or bitter) recipe I made up specifically for onion failures. As I seem to have a lot of those on hand.

It uses just the tops of the onions. No bulbing required. It’s more of a winter recipe anyway. So I will be happy to have it this December if, or when, these onions don’t make bulbs. Instead of onion-failure-fueled depression, I will use the nice green tops and have lovely, civilized, vegetarian “meatballs”.

And I will say that I meant to grow those onions, precisely that way, just for this recipe, all along.

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