How to Grow Real Wasabi

how to grow real wasabi at home

Being someone who likes the real deal when it comes to food, I felt a little bit duped when I learnt a few years ago that the Wasabi paste I’ve been buying in the supermarket is just grated horseradish dyed green.

I started doing a bit of research and learnt it was being grown here in New Zealand on a trial basis in the incredibly clear waters downstream from Te Waikoropupu springs over the hill in Golden Bay but I couldn’t get hold of any.   Thinking it was an aquatic plant, I put the idea of growing it aside.

Then a couple of weeks ago I found a little Wasabi plant in a pot full of soil at the Nelson market and decided to give it a grow.   Canvassing the opinion of Country Trading Co. friends in the social media soup, I found out that it can indeed be grown in soil but it just gets slightly hairier roots than if grown in running water.   While it likes water, it doesn’t like being waterlogged, so good drainage is essential.

Wasabi is a perennial Brassica, similar to horseradish, but with a sweeter aftertaste.  It likes a shady spot, lots of rich compost and is bothered by few pests, with the exception of snails and white fly.   It seems viable to grow it without a lot of sprays, and it can’t be too frost tender as its natural environment is on the shady wet banks of mountain streams.

It is the rhizomes that you harvest to make wasabi paste and they take a full 18-24 months to develop and can be up to 6-12 inches long.   They are used for making the true wasabi paste, but the leaves can also be used in salads and the stems can be pickled or to grow wasabi

It likes to be planted with the crown slightly above the soil.  The plants will eventually send up tall flower spikes which will set seed.   You can grow Wasabi from seed, but it requires a stay in the fridge for a month or two to simulate a cold winter and then prefers the cooler spring or autumn temperatures to germinate.   You can also grow it from the little offshoots that sprout out around the crown of the plant.   These can be removed and replanted when you harvest.

Harvested rhizomes can have coloring from cream to green and they can be stored fresh in a refrigerator in iced water for up to a month.   Once grated they quickly lose their pungency.   In Japan the best Wasabi is served fresh, washed, peeled and taken to the table for grating into paste with a traditional shark skin wasabi grater.

Wasabi paste is not just for sushi.  One of the best meals I’ve ever eaten was hot smoked salmon with a creamy dill and wasabi mayo.  It is a dish I’ve recreated at home several times and it is divine.  Wasabi paste is also used in noodles, sashimi and mixed into dressings or as a last minute topping for grilled fish.   If you cook it you will lose the heat and fragrance so add it to cooked dishes just prior to serving.

grow wasabi

The flavor and fragrance of real wasabi is very different to the imitation wasabi we’re used to.  For a start, it is not fluro-green and the fragrance is delicate.    The taste is intense, but not burning.  As well as a great culinary ingredient, fresh Wasabi is also full of isothiocyanates, which are very anti-bacterial.   Handy for eating with raw fish.

I’m looking forward to my harvest, even if it is two years away.   As I learn more about growing and processing this pretty little plant I’ll come back and update this post for you.   And if I get some seeds I’ll be happy to share them.

If you can’t wait to grow your own but are after a taste of the authentic wasabi, you can purchase a beautiful fresh wasabi paste grown and made right here in New Zealand by




  1. I’ve got a great recipe for eye fillet with lime wasabi vinaigrette (lime juice, wasabi, sesame oil and soy sauce), served with rocket and toasted sesame seeds…..great dinner party main for meat eaters, can be served hot, warm or cold. Guess I need to get planting too, but will check out coppersfolly in the meantime!

    1. Oh Karen, that sounds delish. I’m going to give that a go. I’ve just bought a big old laundry tub to plant my little plant out into and filled it with a mix of pumice and potting mix. Will let you know how it grows.

  2. Hi, great article thanks – do you know where wasabi seeds can be purchased? i just can’t find any.

    1. Hi Justin, sorry I haven’t seen them. The plants are mostly propagated by division in NZ as I think the seeds have a short viable time.

  3. Hi there,

    Can you please let me know where we can get wasabi seeds from?

    1. Hi Emma, I don’t think you can get the seeds commercially but you may find plants.

  4. Interesting. Did the wasabi plant(s) survive? Any followup on this?

    1. My drainage blocked up and they got waterlogged and “drowned” unfortunately – they were doing so well too. I intend to repeat the exercise when I get new plants.

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