The greenhouse is now playing host to all of those plants that need a bit of protection over the winter, cheek by jowl. Wasabi is not one that needs it, and yet I have found a corner for it anyway. I have been growing wasabi – the stuff that you dab delicately onto sushi and that feels like you’ve snorted chilli powder if you overdo it – for a few years now. It is the finely grated root that you will find alongside your sushi, or rather it often isn’t, as the real stuff is replaced with cheaper horseradish and given a blast of green colouring in lots of cases in order to keep costs down, and this is why it is not a bad idea to grow your own and get the full wasabi experience. But my sushi habits are fairly low key, and as such I find I don’t have such a huge need for wasabi root that it really warrants digging up an entire plant to grate its root. The leaves however are a different matter, and I am slightly addicted. They are soft and round but most importantly they contain all of the flavour of wasabi but with none of the nasal hair-scorching heat, a lovely and mild but weird and interesting addition to a salad.
Now wasabi is really no trouble at all. It is perfectly hardy and will survive outside all winter, but yet I find myself squeezing it in anyway, even though space is scarce. Because ‘survive’ is the word. Even though it is not in any danger in the great outdoors – it hails from Japanese mountain stream sides after all, where I imagine it gets hit by more than the odd frost – it will not be producing any leaves outside over winter. Wasabi leaves are at their best in spring and autumn, and die down in the heat of summer and the cold of winter. That is fine but I find that by moving my plant into the greenhouse I get a few more weeks of decent leaves in autumn, and they start up into growth earlier in spring too.
It is also not a bad time to be thinking of other interesting salad leaves, and sowing some winter lettuce. We are a little later than ideal, but lettuce doesn’t like heat, so there should be no trouble getting some of the winter varieties such as ‘Marveille de Quatre Saisons’ and ‘Winter Density’ to germinate if the weather is fairly mild. What they do have to contend with is a pretty steep drop in light levels and in day length, which may limit the amount of growth they are able to put on. Im not going to be growing big heading lettuces from such a late sowing, but if I sprinkle them thickly across a seed tray I should still be able to grow a good showing of baby leaves that I can snip when they are just a few inches across. If all else fails they should sit fairly contentedly over winter and be ready to plant up into pots in early spring. A few planted out per container will quickly bulk up when days start to lengthen, and I can place them near the back door and have them near to hand (which will also have the added benefit that proximity to the house offers them the tiniest bit of protection from the worst of the elements). With a bit of luck they will coincide with the new early wasabi leaves too, and the first of the primrose flowers, and I make some weird and wonderful garden salads.