Celeriac is one of those vegetables which tests anyone with an allotment. It has a long, long growing season – potentially nearly a year, if you count the time from sowing the seed in March until the following February, when you could still be harvesting as I am now. Why, some might say, would you grow celeriac when they are relatively cheap to buy in the shops?

But I refuse to apply this rule to anything at the allotment – first, because I don’t particularly grow veg and fruit to save money, I do it for enjoyment, second, because the taste of any home-grown veg is always superior to anything bought in a shop or food market, and third, because I have followed this crop from seed to harvest and I know exactly what has, and has not, gone into it – no pesticides or nasty chemicals, just composted manure in the soil, water and organic plant food.

And it doesn’t have to be such a long season – you can hold off sowing until April, and I harvested my first celeriac in October. I am making it Star of the Week because the harvest is coming to a peak now, adding a strong, distinctive flavour to mash and soups and keeping us in remoulade. In a couple of weeks the celeriac will be finished for another nine months. By harvesting from October to February, this crop works brilliantly in different recipes according to how cold it is outside – see below for three dishes which reflect the changing season. You can order your celeriac seed now to get ready for sowing next month.

Last March I sowed two varieties, ‘Prinz’ and ‘Monarch’. ‘Prinz’ has a very potent celery smell, while ‘Monarch’ is less knobbly and has an RHS Award of Garden Merit (AGM). I started them off about five seeds to a 5cm pot, in a total of 5 pots, in a heated propagator indoors at about 18C. Once they germinated they were taken out of the heat but kept indoors and potted into a module tray, one seedling per cell. In late April they were moved  into the cold frame at the allotment.

 

Celeriac seedlings need protection from slugs – I used slug-eating nematodes for the whole of last season at Plot 35a and this was enough to keep them at bay. Once they put on a decent amount of growth, by mid-June, I planted them into an open bed that had been dug with composted manure.

The plants need to be kept well-watered and the ground around them free of weeds. The leaves are already beginning to take on the aromatic scent of celery, and the plants put on plenty of leafy growth during the summer months.

Once the celeriac itself – which is a swollen stem base rather than a root – started to bulk up in September and October, I removed the side shoots so they could concentrate on the crop. In October I harvested my first celeriac – it wasn’t huge but I couldn’t wait to make remoulade.

In October, when it was still quite warm, remoulade is a crisp and refreshing dish. Once it got colder and closer to Christmas, I made the vegetable into soup and mash.

To prepare, cut the stringy roots from the celeriac and scrub – there will be a lot of soil around the base. Peel like a potato or parsnip – unless you are roasting it whole, in which case it just needs cleaning and the leaves trimming before being put on a low oven, sprinkled with salt and oil, for about an hour and a half.

For a classic remoulade:

Two medium or one large celeriac, cleaned and peeled

Juice of one lemon

4 tbsp mayonnaise

2 tbsp Dijon mustard

Salt and pepper

1 tbsp cream (optional, and I don’t think it’s necessary)

Cut the celeriac into matchsticks – some people grate the vegetable instead but I think doing it this way loses the firm texture and it can get too watery. Drench the celeriac in the lemon juice which will help it hold its colour as well as give it a proper zing. Separately, mix the mayonnaise with the mustard, salt and pepper and then stir in the celeriac. This is amazing on hot buttered toast. The remoulade will keep in the fridge for 3 days – but it will be in such high demand it won’t last that long.

 

Celeriac, potato and spring onion mash

If remoulade is a late summer or early spring freshener, this mash is a great season-splicer – bringing together, particularly, late winter into spring, with the bite of the spring onion stirring you from too much wintry sleepiness from the other veg. It is hard to go back to plain old mash after having the more aromatic celeriac version.

Serves 4 as a side dish

2 medium or one large celeriac

3 medium potatoes, preferably a floury variety like Sarpo Mira (a maincrop variety that I harvested well into winter) which is ideal for mashing

4 spring onions, finely chopped

2 cloves of garlic, finely chopped

Parmesan for grating

Salt and pepper

Generous helping of butter

Peel and dice the celeriac and potatoes and boil them in water until they are soft, then drain. While the veg is boiling, fry the spring onions and garlic in olive oil until they are golden brown and then remove from the heat. Mash the celeriac and potatoes together with the butter, salt and pepper then stir in the garlic and spring onion. If you’re serving this alongside a roasted joint of meat, keep it warm in the oven with grated parmesan sprinkled on top.

Celeriac also works incredibly in a warming midwinter soup – peel, chop and boil it alongside potatoes and carrots but steer clear of parsnips, which would clash. Fry one onion in oil and throw in a chopped up stick of celery until translucent but not brown. Add the boiled veg and a litre of vegetable stock and simmer for 20 minutes. Remove from the heat and blitz in a food processor. Put back in the pan and add cream or creme fraiche until it becomes silky – but not too thin – and heat gently. Serve with leaves of watercress on top.