This year I am being adventurous in my veg growing again and trying a few things I have not grown for a while. These include some perennial veg and in addition to oca and yacon I have a new strain of Jerusalem artichoke and some seeds of a special purple globe artichoke – of which, more later I am sure. But the most exciting of all is a plant I have not grown for more than a decade: Japanese artichokes.

I last grew these about 15 years ago and they were a delight, and they persisted for several years until the patch got overgrown and disappeared. But the experience taught me a lot and should help with this second effort. But first, and before I describe the pros and cons, and what they taste like, the basics.

I like the idea of growing and eating these because we are supposed to have a diet comprising as many different things as possible. It is astounding how so few (basic) plants make up the majority of our diets. As previously mentioned, brassicas, comprising cabbages, cauliflower, broccoli, sprouts and kohl rabi are all the same species and close relations include turnips and their kin include most Oriental greens. The Solanaceae provide the essential potato and tomato as well as peppers and aubergines, the onion family provides leeks, onions, shallots and chives and the carrot family gives us carrots, parsnips, fennel and host of herbs.

The Japanese artichoke introduces a new family even though it is not related to the other artichokes. ‘The others’ are the Jerusalem and Globe which, though not closely related to each other, are both in the Asteraceae – the daisy family. Japanese artichokes are in the Lamiaceae, the mint family, and are Stachys affinis. This is a plant from China, despite the common name. It is a hardy perennial with pairs of roughly hairy, faintly aromatic leaves and, in late summer, heads of small, reddish pink, typically ‘labiate’ flowers. It grows to about 60cm high. It is hardy and it can be left in the ground all year – something that is useful because it is difficult to harvest all the tubers. It prefers well-drained soil and will tolerate some shade. It is perfect for permaculture.

It is not grown from seed but from the strange rhizomes. These as produced as the plant grows and harvested in autumn when the plant dies down. They are rather grub-like with thin white skin. As they swell the rhizomes are constricted at the nodes and the internodes swell. They can be six or seven cm long but are frequently smaller.

So, they are easy to grow. But, the tubers are little b@*&%@s to clean because of the shape. For this reason I suggest planting in very organic soil. The tubers grow close to the surface and they should be planted 8-10cm deep and if you mulch with a fine organic mulch most of the tubers will be in this and easier to clean than if excised from clay or sand. They could certainly be grown in a pot on the patio in multipurpose compost. Planted 15cm apart in a large pot they would make a mass of not ugly foliage in summer and the flowers will feed bees.

In the garden it is best to plant several tubers at each station, 8cm deep and 25-40cm apart. They can be planted straight in the soil from March to April but, as I am not quite ready for them, mine are in pots, to plant out later. Each plant will produce in excess of 20 rhizomes. If grown poorly these will be small so it does reward the effort to water and feed the plants so the rhizomes are a decent size to eat.

The tubers do not have a thick skin and they dry out rapidly once out of the ground so don’t harvest them until you need them or lift and store in damp compost. The problem with leaving them in the ground is that slugs will attack the tubers and, just like the blackbirds on strawberries, they don’t eat all of the ones they attack, they just ruin all of them. Otherwise there are few pests or diseases to worry about.

So, what do they taste like? Well the good news is that you don’t need to peel them! Phew.

They have a crisp crunch when raw and a slight sweetness and a vaguely nutty taste with a hint of something herby. The taste is delicate. You can cook them too, either boil, steam or stir fry but they cook really quickly and once overcooked they are mushy and a bit pointless.

I think this is a veg that is more appreciated in other countries and it is often called Crosnes de Japon (especially in France!). This is because it was first grown, in France, in 1882, by a Mr Auguste Paileux in Crosne, Essonne in France. It was popular a century ago but, apparently, fell from favour because of virus infection. I hope my stock is free of it. I certainly didn’t notice in the past.

Of course the problem is finding them to plant in the first place. If you can see them for sale to eat then you can plant some. This might a possible if you shop at Harods. You may also find a stockist of planting tubers. I was happy to find a French stockist in my search for supplies from the EU now the UK has isolated itself, but there are suppliers in the UK.

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