Hi, y’all! I thought it would be nice to have a thread about sunchokes (Helianthus tuberosus, a.k.a. Jerusalem artichoke, which is clearly a brilliant and not at all a confusing name for a North American sunflower ).
This is my third year growing them, and I have found them a terrific crop for my climate: Utah, zone 7b cool wet winters, very hot and arid summers.
Here are my experiences so far, in case this interests you.
In general, I find sunchokes to be vigorous and drought tolerant. They would probably do great dry-farmed in most climates; in my climate, with 95-100 degree temperatures with little to no rainfall for five months, they do great with deep wood chip mulch and being watered every two weeks. They start to wilt a bit and look complainy if I forget to water them for a whole month, but they will generally recover just fine; they just won’t produce quite as much of a harvest if I don’t water them twice a month.
They’re vigorous enough that I can plant a tuber an entire foot down, covered in deep wood chip mulch, and it’ll grow up through it just fine. Sometimes this can be a bit of a nuisance if I decided to move my sunchoke patch and seem to have missed a few small tubers somewhere. (Laugh.) But it’s easy enough to remove unwanted sunchokes – when you find a sprout, you follow it down to the tuber and pull it out and put it somewhere you want instead.
Just keep in mind that you’ll pay a cost if you move them while they’re actively growing: the top will die off, and it’ll go dormant until next spring. So if you see a sunchoke sprout in the wrong spot in April and dig it up and put it somewhere else, you won’t see it sprout again until next April. I find that a bit of a bummer.
Sunchokes are supposed to be a little allelopathic, like other sunflowers. I’ve grown them next to peach and fig trees, both of which seemed to be unbothered by them.
I think they may have an allelopathic effect on morning glories, because bindweed seems to be less prevalent near them. Works for me! They may also discourage cucurbits and brassicas from sprouting; I haven’t seen much germination of those seeds planted next to sunchokes yet. But that may just be because I water the sunchokes so infrequently.
I’ve heard legumes are immune to sunflower allelopathy, and I’ve grown vigorous peas right next to sunchokes before. Sunchokes make a decent living trellis for peas. The main problem is that peas sprout in January/February and sunchokes sprout in March/April, so the sunchokes aren’t tall enough to serve as trellises by the time the peas need them. They’d be excellent trellises for my August-sown peas, but my August-sown peas keep growing all winter, so they’d get in the way of harvesting the sunchoke tubers. I’m thinking sunchokes might be a good trellis for drought tolerant summer legumes, such as cowpeas.
Don’t rush to harvest sunchokes. If you’re still harvesting squashes, the sunchokes are several months away from being ready. Most of the tubers form in late fall, at least in my climate. If I dug them up in September, there would be nothing. Late November might be okay, but I generally won’t touch them until early December, at the earliest. I usually wait until Christmas. There’ll usually be about twelve tubers per plant around Christmas.
There’s another benefit to waiting that long, which is that sunchokes taste best in the winter. They’re sweeter. They’re also way more digestible.
Sunchokes are chock full of inulin, a powerful fiber. This is awesome, unless you eat too much. If you’re not used to eating inulin all the time, do not eat three at one sitting. Eat one tiny tuber, or even half a tuber. Do that every day for a week. Then you can start eating twice as much. If you are used to eating inulin every day – I am, because it’s a fabulous food that tastes exactly like sugar but is actually pure fiber – then eat as many sunchokes as you feel like.
Sunchokes taste very similar to potatoes; the main difference is that they are slightly sweet. There’s a little bit of a difference in flavor other than that, which I think comes from the skin, because that slight flavor is noticeable in my purple sunchokes and not in my white ones. It’s not very strong, and to me it tastes fine. If you don’t like that flavor, peel them or grow white sunchokes.
Sunchokes have a very poor shelf life. You can’t store them dry at room temperature, unlike potatoes or sweet potatoes. You can harvest loads, stick them in a sealed bag, and then stick that bag in the fridge, though. If you do that, they’ll probably be fine for a few months. If your soil freezes solid during the winter, I would probably recommend doing that. If your soil is often soft during the winter (like mine is), I recommend just wandering outside and pulling up a few whenever you want to eat some.
You can start sunchokes from whole tubers, or even little chunks of tubers that have at least one eye. I was delighted to discover the latter works fine. However, the larger the tuber (or chunk of one) you plant, the larger your harvest will be at the end of the season. So I tend to eat the small ones and replant the large ones. It seems to be a better investment.
I recommend you pick varieties that are easy to clean. I have tried Beaver Valley Purple, Mammoth White, and the Joseph Lofthouse landrace. Mammoth White is very productive, but the tubers are very knobby and a bit of a pain to clean mud out of. Beaver Valley Purple and the Joseph Lofthouse landrace phenotypes all produce tubers that are more of a single bulge, with a few extra bulges on the ends of the biggest that you can easily break off and clean separately. They all grow well in my climate, and they all flower and can produce seeds.
Grown in my climate with very little watering, Mammoth White and Beaver Valley Purple both flower in August, and the Joseph Lofthouse landrace all flowers in September. I can generally harvest finished seeds from them all in late October or early November.
Sunchokes do not seem to be very productive about growing seeds. If I’m lucky, I can find seven seeds in one flower. It’s more common for me to find zero seeds (that’s about half the flowers) or one or two seeds (most of the rest). This may be a pollination issue, it may be a drought issue, it may be birds eating the seeds, or it may just be that sunchokes aren’t very productive at making seeds. I will generally get about 10-15 seeds from the biggest plants that have flowered a lot, about 1-5 seeds from any medium-sized plant with a few flowers, and zero seeds from the rest (which is about half the plants).
As a side note, both Beaver Valley Purple and Mammoth White seem to do better in extreme heat than the Joseph Lofthouse landrace, but the Joseph Lofthouse landrace seems to sprout earlier before the last frost and stay green longer after the first frost, so his landrace is probably ideal for a climate with cooler summers and a shorter growing season than mine. Which would make sense, since his climate fits that description.
I hope those tips are helpful! If anyone else has any tips they’d like to add, feel free! I imagine growing sunchokes can be different in every climate.