Eutrema Species, Wasabi, Japanese Horseradish

You've probably been told discouraging things that made you shy away from growing wasabi, but be discouraged not.

This sp...Read Moreecies is predominantly shade loving, but accepts some morning sun without trouble. Of 10 small starts planted in containers in early spring, 2 failed quickly, leaving 8 survivors. Growth medium is a mixture of 2/3 hardwood compost and 1/3 pea gravel. This container grown media is well drained, with plants watered every morning until well rooted, and given periodic doses of fertilizer. Plants remained in active growth in cool weather, with growth gradually slowing as a long, hot summer arrived.

It is often claimed that wasabi does not survive in hot climates. This is not my experience. My own container grown plants have withstood our longest, warmest summer (Zone 8a) on record, with daily temperatures of 90-96F (32-36C) persisting until the beginning of November, without wilting or obvious distress. The key seems to be maintaining adequate humidity (e.g. 50+%). In very hot weather, plants should be kept fully shaded and watered once or twice per day in accordance with ambient humidity levels. Growth slowed dramatically in these conditions, but the plants remained otherwise healthy.

For the winter, containers have been moved indoors to protect from hard freezes. They are kept at 65 F (18 C), in moderate ambient lighting, and given regular water spraying. Active growth has returned to pre-summer levels. The rhizomes are thickening, and the plants are propagating themselves, as new independent shoots have suddenly appeared away from the mother rhizomes.

Be advised this plant is incredibly attractive to slugs.

Note: Many S.E. Asian Ebay sellers advertising "wasabi seeds" are actually selling seeds of "wasabi mustard," Brassica juncea.

i purchased a packet of seeds from somewhere. Just a few seeds inside. Only one of them germinated. It's about 6 months later now, mid De...Read Morecember, and it's thriving in a Southern California winter. Really enjoys the rain and low temps.

This is a hard plant to keep happy but (so far, for me at least) it has proven resiliant to several lapses on my part. There is a lot of...Read More conflicting information, even taken directly from the mouths' of the growers.

I got my first Wasabi from "The Frog Farm" in Seattle; I was in town and the owner graciously allowed me to drop by and see his set-up: deep beds of heavily composted soil covered with a shade cloth, watered regularly (I believe he said first thing in the morning then again in the hottest part of afternoon.) He told me that they had never had disease from repetedly deviding the roots which is a common story you hear from Wasabi pureists. I got a mature specimin that would eventually devide into 3-4 seperate plants and almost as soon as he had it out of the ground it started to look like a wilted lettecue. Watering did pep it up a bit but, over time, most of the old growth died off and regrew later after planting.

My second Wasabi came from a local OR nursery who just gave it too me (They had had enough of the demanding nature of Wasabi's and it was a kind of "Thankyou" for a big purchase "Here," they said, "It's free if you can bring it back to life.")

I put them both in full shade along the North side of my house. Unfortuantly I picked the most clay ridden spot in my yard and the compost I added was only enough to keep them alive; they never thrived. They were unmulched over the 04-05 winter and they actaully seemed to grow in December (they sure love cool temps and lots of rain.) The 05-06 Winter was much colder and I panicked a bit; dug them up and brought them inside with about 50% compost and 50% sand in the pots...then I forgot about them = no water for god only knows how long...they were brown nubs peeking out of dry sand when I finally noticed them. This spring I brought them out with the rest of my Over-Winterers and could not have been more thrilled to see new growth after a cold rainy April.

I also tried to grow Wasabi from seeds purchsed from http://www.freshwasabi.com and though I followed their growing instructions to-a-t not one of them sprouted. Note: a member of thier staff told me they tried to root-devide thier Wasabi stock only to have severe problems with disease.

In Nature Wasabi grows along the gravely banks of cold mountain streams and can therefore take more sunlight. I've read horror stories about hydroponic exparaments failing because of recycled water but cannot confirm them personally. Good luck to anyone who attempts to grow Wasabi...I feel your pain.

Grown mainly for its edible, pungent roots that are used like Horseradish (Armoracia rusticana). The long, finger-thick roots los...Read Moree their pungency once cut. This is not a quick-cropping plant - it can take 3 to 5 years from seed to harvest and the seeds are reported to be reluctant to break dormancy.