[Mr Dog]

This is how I grow Celeriac.

First do not grow the variety Prague Giant. I grew it year after year and they never grew larger than golf/cricket ball size. The skins are very knobbly too meaning more waste when preparing them. I have been growing Monarch from DT Seeds with better success. This year they are grapefruit size and the best yet. DT Brown is offering a F1 hybrid celeriac so I shall try that next season alongside Monarch.

Second Celeriac needs a very long season of growth. I sow the third week of February grow them on in pots or modules and plant then out late april/early may depending on the weather under fleece to keep the cold off. A dressing of chicken pellets (or growmore) and another couple of applications throughout the growing season.

I try to keep them well supplied with moisture though I don't flood them as you would do celery.

In September the outer leaves begin to lay horizontal to the ground. I pull these off exposing more root. It may be my imagination but the roots seem to benefit from this pulling.

Finally I don't  begin using them until November so they have had as much time to swell as possible. A light frost does no harm. However they must be dug up before hard frosts begin else they will turn to mush.

It is still very much work in progress but I believe I'm finally getting the knack with celeriac.

I've successfully grown the F1 (Ilona) for the past few years.