I would imagine summer heat would be your biggest problem. I know people that grow celery, but they really have to baby it and it is only a cool season crop. Celeriac needs all year to make the bulb, so you would start in the spring (or late winter indoors) and then do anything you can to help it through the summer and then harvest sometime in the fall or winter. Good Luck.

John, would some kind of filtered shade reduce the summer sun impact?

I don't know - a lot of plants from cooler regions of the world want full blazing sun with cool daytime temps. Which is why we struggle to grow them here.

If it were my garden I would sow all the seeds, thinking that some of them might handle the high heat better than the rest.

I grow rhubarb which rarely does well this far south and this close to the ocean (does fine in the mountains of NC). I have never had a plant make it for more than 3 years (but others have). I just plant a few each Spring. If some return from last year - fine, if not, then I still get a few pies.

I haven't grown celeriac so I don't know how long it takes for the swollen root to form. I would think it would be like growing brussel sprouts which take all summer for the plants to get big enough to form the signature sprouts on the main plants stems.

Trianglejohn: I think your method of generously sowing celeriac seeds directly would be perhaps effective but costly beyond any budget.The seeds are very tiny and rather expensive.I started them in tray and will report back on success or dismal failure most-likely later in the year.Oh,why I brought with me a taste for all those colder-climate vegetables!

I started celeriac last Spring in small cups from seed. Planted the seedlings here and there, a couple in lots of shade, some in total sun. (about 10 in all) None did that fantasic, just used a few leaves for soups and such. Forgot all about them. Was out preping some of my gardens this week and the cleriac is looking awesome.(In both areas) Big plants, no thickening of roots though. I'm very hopeful that by April/May, they will.

Ah, Rhubarb. I've two plants that are living strong three years now. This year I've 20 plants started by seed (Dec.) and are up and doing good. It is a warm weather variety, up to zone 8. Half of them I will keep in ground all year. The other half I will dig up this Fall and put roots in bag in Freezer for 6 weeks or so before I replant around Feb 1st. Heard it works. Will see.

Thanks,Lorabell! That gives me some needed encouragement.In my greenhouse I grow Chinese celery and the taste of the leaves is exactly like celeriac.They don't form any bulb though.

Lorabell, that's a great message regarding digging some of the rhubarb roots and chilling them for 6 weeks then replanting. We're probably going to have to use that method to more perennials and bulbs in years to come.

I think that 70 degrees would be the magic temperature to get the seeds to sprout - which many people find easy enough to do inside the house. Once the sprouts have a few real leaves they can handle much colder temps and they should be easy to harden off by placing them outdoors as long as the night time lows aren't below 30. After the plants get bigger they could probably handle a hard freeze if they were in the ground. So basically they would be grown like cabbage. It seems to me that cold climate plants can tolerate high temps for a while, but the more days spent above 80 the more problems they have. It's kinda like the reverse of chill hours for warm climate plants.

You could sow some of the seeds this spring and another batch late July as a fall crop. Our winters are usually mild so both groups could be left in the garden to see when they'll form the swollen root.

I once had some world traveling friends present me with seeds from Europe for all sorts of heirloom veggies. I was thrilled until someone that spoke Italian translated the name and all of them were mainstream US varieties, available from any heirloom catalog. Someone that does crop research told me that there is only like 5 main seed companies for the entire world and that the only way to get something really unique is to get gardener harvested seeds.

Thank You,Sir for that excellent advice.I agree that planting celeriac twice gives twice the chances for a success with bulb-forming,which is the whole point of growing it.
It brings to my mind my unhappy adventures with attempting to grow the type of parsley that has the big,white root-no smaller than large carrot.The plants would have splendid plumage of foliage but only tenacious,spindly root.

My motto is never give up! I have seeds sitting in pots that have not sprouted nor have they rotted for more than three years. I can wait. Gardening will teach you patience.

That is just what I love about botany: the kind of time it introduces us to: the lichen time of majestic slowness where there is enough time to think,to pay close attention, to wait gladly.

A celeriac purchased at the grocery store is happily setting roots out in a jar of water. My hope is to cut it into sections, each with strong new roots, and plant these out.

Has anyone had success with propagating celeriac from the grocery store roots?

I am hoping to get many plants from one celeriac knob.

I would think cuttings from the sprouting root would work but you would have to keep an eye on them to watch for any signs of rot. Cool weather with lots of light should get the sprouts strong enough to be easy picking. You may not even have to slice up the big root - the sprouts may pop off easily once they get four or more leaves.

I have seen Parsley Root seeds for sale so someone has to be growing it. It may be one of those plants that would be better as a fall/winter crop. As hot as late July and August are, they are the perfect time to sprout cool crop seeds - indoors in seed flats and then move them outside when September starts to cool down.

I am worried about rot, too. This has had me wondering whether root cuttings would grow. There is so much "bulb" between the roots at the base and the shoots, when and if they appear, that rot seems nearly inevitable.

I'm thinking about cutting the roots off the "bulb" with maybe 1/4" of the flesh attached. Then, keeping the flesh above the soil line, plant the roots and hope that shoots appear. Once they do, dividing sections with root and shoot should be easy. Do you think this method will send up shoots? Should I dust like one dusts seed potatoes to help prevent fungus?

I would use the fungicide dust and I would make sure I used sterile potting soil and just to be safe I would fill each pot an inch or so from the top and then fill the rest of the way with clean sand or fine gravel. I would only water from the bottom try real hard to keep the top layer dry (this trick helps with fungus gnats also). Some people sprinkle cinnamon on the surface because it is supposed to be anti-fungal and repels tiny pest like gnats.

I would think that if the root was busy sprouting and the sprouts were growing fast, you could get enough plant growth before rot set in. The trick would be to find the perfect temperature and light settings to keep the growth chugging along. My guess would be 70 degrees and at least 14 hours of light (trying to mimic springtime). You could also just wait and buy a root at the grocery store in April and then set it up for sprouting during May.

Digging around in seed catalogs, the info on Celeriac says three months of growth before a bulb starts to form. They say nothing about protecting from summer heat or only growing in northern zones.

Of course, now that you've "planted the seed" I will have to try and grow some. Next time I see a root in the grocery store I will probably buy it and try and sprout it.