Stored in the fridge through recent months, we had celeriac in beef soup with pearled barley, today. Carrots, onions, garlic ... bay leaves.
My one attempt to grow celery was an embarrassment. It amounted to nothing. After that, I wanted to try celeriac but had no real expectation that it would work. I associate celery with the Monterey Peninsula in California. This is very different country and climate here

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Twenty plus years later, I am still growing celeriac and enjoying its starchy roots, mostly wherever it makes sense to have them with or replacing potatoes. For one cup, the USDA says peeled and boiled celeriac have 41.8 kcal. Peeled and boiled potatoes have 134.2 kcal. Less than ⅓rd the calories but not "0 calories" as reported in your article for celery.
We still buy and use celery — we like celery flavor

. Maybe I will try growing it again but, there's no question, it will not store as well as celeriac and I never see those roots in local stores.
The plants require an early, indoor start and the entire season. They do seem to really require a complete fertilizer. Our well-drained soil works for them and irrigation 2x/week, with 3/4" of water each time. That frequency seems a minimum for a good harvest.
Steve