Wasabi, horseradish and friends

Sushi fans will appreciate this forest garden plant: Wasabia japonica or plain wasabi. Wasabi grows best in shallow running water in dappled shade – fairly demanding conditions that don’t occur in a lot of gardens – but I’ve found that it does okay in the light, sandy soils of my allotment so long as it has some shade and is watered in particularly dry weather.

Wasabi takes a few years to come into full production. It is the taproot that is used: finely grated and then pounded into a green paste it gives that kick that I must confess to being a little addicted to. The leaves are also edible, with a much milder wasabi flavour than the root, so they can be used in dishes where you want a finer control over the heat. However, wasabi is only the most recently fashionable of a whole group of plants, all members of the cabbage family, that have a similar flavour and uses.

The king of these is undoubtedly horseradish (Armoracia rusticana). In fact, if you buy wasabi powder in the West – and even sometimes in Japan – take a look at the ingredients list: you will most likely find that it is made from horseradish powder and green dye. This popularity is not because it tastes better than wasabi but due to the fact that it is an extremely easily grown and productive plant. It is perhaps best not to give it its favourite conditions – a damp soil in full sun – as it is then said to be invasive. My plant is in light shade in a deep, free-draining soil and seems both perfectly happy and well-behaved. Horseradish roots can be harvested any time when the plant is dormant by digging up the plant and taking off some roots, which will then store for a few months if kept cool and moist. You don’t have to be too careful as it regrows easily from pieces of roots, which is also the way it is usually propagated.

Horseradish – from Wikipedia Commons

Ungrated horseradish roots have very little flavour, but once they are cut the damaged plant cells break down a substance called sinigrin into fiery mustard oil, a protective ploy against being eaten by less perverse species than ourselves. This volatile oil is easily lost, being broken down by exposure to air or by heating, so horseradish is generally added to dishes at the end of cooking and needs to be used quickly. Grated horseradish’s shelf life can extended by combining it with vinegar: horseradish sauce is made with both vinegar and cream. Even then, however, it only lasts a few months before losing its savour, making it worthwhile to have your own plant. I also find that freshly grated horseradish has a sweetness and freshness that a sauce just can’t match.

Dittander (surrounded by wild garlic)

Before horseradish was introduced to the British Isles, two other, native, plants were used for a similar flavour: garlic mustard (Alliaria petiolata) and dittander (Lepidium latifolium). Both have a superior flavour to my mind, but the roots are much smaller and more fiddly to prepare and I wouldn’t recommend growing them for this purpose. Both have edible leaves though, and those of dittander are especially interesting. Alone amongst the other plants, they have a strong horseradish flavour in their leaves as well as their roots, giving them the nickname ‘wasabi leaf’ in my garden. This gives an extremely easy way of adding wasabi flavour to everything from salads to cooked dishes (finely chopped – they are strong!). Perhaps they could be used to make sushi with integral wasabi flavour. If you have too many dittander leaves they can also be used as a pot herb as they lose all their kick when cooked for a few minutes. Dittander can tolerate deep shade and is an invasive spreader if allowed to be, so grow it in a pot sunk into the ground like mint.

Finally, the most decorative form of horseradish flavour is in the flowers of lady’s smock (Cardamine pratensis, also known as cuckoo flower), a native cress growing in damp and shady places.

Lady’s smock

The heat of horseradish can be used in two ways: by matching it with other strong flavours or by using it to spice up blander foods, especially starchy roots and oily, creamy dishes. Classically it is used with strong-tasting meat or fish but there is much, much more to horseradish than this. Scrambled eggs with horseradish root grated into them are superb, or you can try adding it to a creamy pasta sauce at the end of cooking. Mashed potato is another dish that is enhanced considerably by horseradish flavour – if you substitute wasabi leaves for cabbage you can make an amazing variation on colcannon or bubble and squeak. Adding horseradish to soups – again at the end of cooking – gives quite fine control so you can add a very delicate horseradish flavour if you like or go for the burn. For real addicts like me, you can even make a horseradish salad dressing with fresh grated horseradish combined with olive oil, lemon and salt.

Horseradish is sometimes combined with mustard – a similar flavour but more aromatic and complex – to make Tewkesbury mustard, as in this horseradish and root vegetable bake by Nigel Slater. The same combination is used in horseradish butter –  butter, grated horseradish and mustard blended together – which can then be used on dishes like sweetcorn.

More horseradish recipes (including Bloody Mary with horseradish and horseradish-infused vodka!) can be found at http://localfoods.about.com/od/horseradish/tp/abouthorseradish.htm

Eating rhubarb flowers

There’s an unusual perennial vegetable lurking unsuspected in many gardens at this time of year: rhubarb flowers. You should remove the flower stems from rhubarb to stop it wasting its energy on seed production in any case, so instead of chucking it on the compost, you could use it, as they do in the far east, as an exotic seasonal ingredient.

The secret to preparing rhubarb flowers is to know that the tiny individual flowers that make up the head do not contain any oxalic acid, the substance that makes rhubarb so sour, but the flower stem does. The stem is a branching structure that goes right inside the head so you’ll never get it all out, but if you just cut off the most accessible bits you’ll have got rid of most of it. Also be sure to remove the stem leaves, which are presumably as poisonous as the basal ones, and the papery bract which surrounds the flower head.

The result is still sour, but interestingly rather than overpoweringly so. It goes best in dishes where there is a sour element and you can often leave out vinegar or lemon juice from a recipe in compensation. I find it delicious boiled for four or five minutes with broccoli sprouts, then drained and served with oil and salt over the top, leaving out the shake of lemon juice that I would usually add. It also goes very well in a stir fry.

More on rhubarb in Rhubarb and elderflower jam, and a surprise.

EU threat to local seeds

I don’t usually use this blog to promote campaigns and petitions, but I think that this one is important enough to make an exception. On the 6th of May, European Union commissioners will be considering a new law which would make the sale or even the free distribution of unregistered varieties of seeds illegal. There would be a process for registering ‘old’ varieties cheaply, but this would still mean that the whole field of breeding locally-adapted varieties and unusual crops by amateur and small-scale local breeders would be outlawed. Forest gardening would be effectively nipped in the bud.

The Commission is divided on this, with the directorate of consumer affairs proposing the law and the directorates of agriculture and the environment against it, so national commissioners will decide the vote and there is a real chance to swing it. There is more detail on the Real Seeds Catalogue’s website.

Please write to your national commissioner, who is Baroness Ashton in the UK.  Her email address is catherine.ashton@ec.europa.eu. I’ve included the text of the email that I sent below. For other countries, the list of commissioners is at http://ec.europa.eu/commission_2010-2014/index_en.htm. Commissioners’ emails all take the form of firstname.lastname@ec.europa.eu

If you don’t have time to write, there are two petitions that you can sign on the Real Seeds page, but a clear, brief and polite personal email counts for a lot more than a petition signature. It needn’t take long: in fact short, clear and to-the-point is much better.

Dear Baroness Ashton

I am writing to ask you to vote against the new law on the sale and distribution of seeds proposed by DG SANCO when it comes up  for your consideration on the 6th of May.

As I understand it, the law will ban the sale or distribution of  unregistered varieties of seeds within the EU, with provisions for the cheaper registration of traditional varieties which are currently commonly traded. This will mean that plant breeding will become the sole preserve of companies rich enough to afford such registration. It will outlaw the huge amount of activity that currently goes on breeding locally-adapted varieties of a wide range of plants by amateurs and small-scale local producers. This activity has considerable economic and biodiversity significance, but perhaps even greater cultural significance.

In my case, I am involved in selecting seed of local wild species for use in forest gardening, an increasingly popular method of growing food in which shade-tolerant food crops are grown under fruit trees and bushes. Many of these species are only available in their wild form and would benefit from selection to improve their characteristics. An example would be sweet cicely, which produces an aniseed-flavoured root related to parsnip and which I am selecting for larger and straighter roots. I currently mostly give away seed but hope to sell some in the future. Both of these options would be outlawed by the proposed law.

It is difficult to see how this law would benefit anyone except for the seed companies which will gain an effective monopoly. It is surely significant that it is being proposed by the directorate for consumer affairs while being opposed by the directorates for agriculture and the environment.

Kind regards

Alan Carter

Growing and eating wild garlic

Very few of the really shade-tolerant vegetables are as productive, versatile and useful as wild garlic (Allium ursinum), also known as bear garlic, ramps or ramson.

When I was young, on a family holiday in Wales, I discovered a wood carpeted with ramsons. Overwhelmed by such exuberant bounty, I stuffed my pockets with leaves. In the car on the way home my parents noticed a certain odour taking over the space and after a quick search my foragings were evicted. I suppose it could have been worse, it could have been me. Nowadays I have my own tame patch of wild garlic in my allotment and I can harvest it when I like.

As with many perennial crops, there is a useful synergy between wild garlic and the cultivated kind (Allium sativum). It starts to be ready just as stored bulbs are usually running out, some time in February or March, and runs through until about June.

Wild garlic can be used pretty much anywhere you want a garlicky flavour, with the caveat that the flavour doesn’t survive cooking for long, so you generally need to add it to cooked dishes near the end. Ramson pesto packs quite a punch. I like to chop it into salads: whole leaves are a bit strong to eat in bulk but chopped roughly and mixed with other leaves it is delicious. Layering a few leaves into a sandwich works well too.

If its garlic flavour were the only thing that wild garlic had going for it, however, it would be best regarded as a herb and grown in a small patch in a shady corner. What makes it useful as a bulk vegetable is the very fact that it loses its garlic flavour when cooked for more than a few minutes, leaving a very tasty, oniony green. As such I use it anywhere where I would use onion, particularly as the base of a sauce, be it pasta, curry, stew or soup. You can also substitute it for spinach for delicious variations on dishes such as lasagne. It makes an excellent pot herb, either on its own or mixed with other leaves that are available at the time, such as annual and perennial kales or leaf beet.

One thing to be careful with is that wild garlic quickly develops a rather unpleasant burnt-onion taste if allowed to dry out while cooking, so you need to take care to keep it moist. In our household we love wild garlic on pizza but we always layer it at the bottom so that the other ingredients protect it.

Almost all parts of wild garlic are usable, including the leaves, stems and flowers. The flowers look amazing in a salad. As it happens, the one part that isn’t worth using is the bulb. It is rather small, dry and stringy and no substitute for the bulbs of cultivated garlic. Not to mention that if you use the bulb, you don’t get any of the other parts. (That said, there is a recipe for pickled wild garlic bulbs - and many others - on the excellent Eat Weeds blog).

You can harvest wild garlic simply by pulling off individual leaves or, for less garlicky hands and to speed things up, you can cut a clump at a time with scissors. I generally put my wild garlic leaves in a bowl of cold water for five minutes as soon as I get home, to preserve and wash them. They’ll then keep for at least a week in the fridge. Another way of harvesting that gives a slightly different product is to dig up a clump and then prepare the individual plants by cutting off the roots and removing the sheath of the bulb. The whole thing then hangs together in a sort of ‘spring onion’ version of wild garlic. Fried in plenty of oil and dipped in a sauce these are gourmet food indeed.

wild garlic clump, separated

Ramsons are an easy plant to grow, flourishing in the parts of the garden that most other plants avoid. They are a plant of deep woodland, so they like plenty of shade and a moist, humus-rich soil. Once you have got them established they will generally self-seed (to the point of nuisance if they weren’t so edible). Their habit of dying down in the summer makes them easy to manage as you can choose this time to top-dress them, mulch them or hoe over the top of the bulbs. They can even be used in a strip as a bit of a barrier against the spread of other plants. During the spring they suppress other plants by the strength of their growth and during the summer you can hoe the strip. Ramsons are capable of growing through quite a thick mulch: their leaves form green spikes that punch up through mulch before unfurling. Alternatively the dormant period is long enough that you could fit in another crop or a green manure, or interplant wild garlic with another perennial that makes use of the later part of the year.

wild garlic – just emerging

Wild garlic will tolerate growing in the open, but as soon as there is hot sun its leaves will burn off and it will retreat to its bulb. It is worth growing some wild garlic in the deepest shade you can find, in which case it will persist until midsummer.

Wild garlic can be raised from seed or, more easily, grown from bulbs. The bulbs do not store like those of cultivated garlic, they dry out and die quite quickly if they are not stored moist. They transplant very well ‘in the green’ (while the bulbs are growing), which also avoids the problem of forgetting where you have planted the bulbs!

One word of warning, whether you are foraging wild garlic or growing it. While wild garlic is entirely edible, it can be growing in with leaves of plants that are quite poisonous, as most of the spring bulbs are. It is hard to mistake wild garlic for anything else when you look closely – the combination of the broad, soft leaf and the garlic smell is unique – but if you are bulk harvesting you might become a little careless. In the photo below you’ll see a patch of poisonous snowdrops growing in about the wild garlic, so if you are foraging, take care, and if you are growing I would recommend removing any snowdrops, bluebells or other spring bulbs from the same bed.

Photo: Monimail Tower woodlands from Scottish Wild Harvests Association’s Forage In Fife.

Real spring onions

Last year was the warmest March on record: this year it has so far been the coldest. Spring ain’t what it used to be. None the less, it’s reliably time to harvest the ‘spring onions’.

I don’t mean the things you buy in the shops as spring onions (or scallions) since I don’t grow them. Let’s face it, onions are a pain to grow from seed. You need lots of added soil fertility and fanatical weeding of things that look regrettably similar to grass seedlings. Then, just as they are starting to look after themselves, you dig them up and eat them. By this time it’s usually August, which isn’t spring, not even here in Aberdeen.

tree onion

Fortunately there are two perennial vegetable species which produce excellent spring onions even when it’s still snowing and with very little fuss for the rest of the year: tree onion (Allium cepa proliferum) and welsh onion (Allium fistulosum).

Tree onion is the same species as the ordinary onion. A lot of allium species can produce either flowers or tiny bulbs called bulbils (or both) in their flower heads and tree onion is a kind of onion that goes for all bulbils. These often sprout when they’re still on the plant, giving it a tree-like appearance. The stem then usually falls over, giving the plant another of its many names – walking onion – as the bulbils put down roots and the plant ‘walks’ around the garden. It also reproduces by bulb division underground, like a shallot or a daffodil.

tree onion divided

This gives two ways to exploit tree onions for spring onions. First you can dig up the parent plant when it resprouts in the spring, divide out some of the bulbs and replant the rest. The other way is to gather the bulbils when they are produced later in the year and plant them out into a bed where they will grow on into very well shaped spring onions. It’s kind of like having a free supply of onion sets for spring onions and yet another name for this plant is ‘topset onion’ (You can also let them grow on into bulb onions, but they tend not to be very big.). You can plant some in the autumn for spring growth as they are extremely hardy but they will also keep well if you store them in a cool, dry place, so you can make successional sowings later on in the year too.

Welsh onion is a different species from regular onion but it’s very similar to tree onion. Instead of bulbils it produces a rather fleshy flower head which can also be used as a flavouring or left to produce seed (picking the flowers stops the plants producing seed and diverts their energy back into making bulbs). Like tree onions they divide underground and can be lifted and divided as spring onions in March and April.

welsh onion divided

Both species can also be harvested by picking leaves in the summer. I find that welsh onion makes bigger and more regular-sized spring onions by division and tree onion is better for leaves, partly because you can use the bulbils to produce a really dense patch. So the best use is probably welsh onions for division in the spring and tree onion for leaves and sets for growing on. If you allow welsh onions to flower you will be very popular with the bees.

Real spring onions can be used in all the same ways that you would use the seed-grown ones. My favourite is spring onion sambar: you fry a large handful of whole spring onions until they are soft, then add tamarind, coconut and spices to make a sauce and simmer for a few minutes. It’s a great way to forget the sleet driving at the window.

Self-seeded parsnips

A few years ago, I took over an allotment that had been abandoned for some time. It was an education in how long any of our cultivated crops would last without us lavishing constant attention on them. The autumn raspberries had taken over one end of the plot and there was still a cheerful patch of rhubarb, a plant that I always assume will conquer the world after a nuclear war, but everything else had disappeared under a sea of willowherb and docks.

When I started digging however, there was one more surprise survivor. A healthy crop of large, well-shaped parsnips (Pastinaca sativa). Judging from how long the allotment had been unused, they must have been several generations away from the ones originally sown by the gardener. I was inspired to allow parsnips to go feral in my forest garden.

Having all but forgotten about them, I dug up my first self-seeded parsnip yesterday. It turned out to be a beauty. It was around 300mm long, weighed in at 700g (one and a half pounds) and, despite my worries that it would be all worm-eaten, was almost flawless.

This particular parsnip was growing under in the shade of an apple tree. The soil it was in is deep and sandy but doesn’t get fed much apart from an annual mulch of leaves. The only effort that went into this parsnip all year was when I dug it up. The remainder have disappeared under a layer of snow for just now, but there seemed to be a good number.

So we feasted on parsnip this evening. First parsnip chips, then noodle soup with parsnip. That’s chips in the British sense of chunky fries, not in the American sense of crisps. Sliced up and deep fried, they cook very quickly and are delicious, fatty and sweet: excellent winter food if perhaps not the most healthy way of enjoying them. Very little was wasted: young parsnip leaves are also edible, tasting to me rather like celery leaves. Some sources say that they can be treated as a leaf vegetable, but I would say they are better thought of as a seasoning. Speaking of seasonings, like so many of their relatives in the carrot family, parsnip seeds are also useful as a spice, tasting a bit like dill. This is very useful for me because we have motley dwarf virus in the allotments which cuts down any actual dill I plant quite quickly.

So far, very encouraging. I’ll keep on allowing my parsnips to self seed, even if that does mean taking the biggest and best of them every year and replanting them to go on and provide the next generation.

P.S. One final use of parsnip: the Plants for a Future database says that a tea made from the root is good for ‘women’s complaints’. From observation of my girlfriend, I can only assume that this means that it helps Linux work better. Very strange.

Paths

There is one kind of plant that really doesn’t belong in a forest garden, and that is grass. When I got my allotment, it had the traditional layout of bare soil beds with raised grass paths between them. The old boys actually seem to enjoy maintaining these structures, mowing the tops to perfection and deploying a range of implements that a hairdresser would be proud of to keep the sides in trim. If this is neglected for even a short while, the grass flops over the sides, first making a perfect habitat for slugs then starting to grow into the beds.

I decided that no matter how much work it took to replace the paths with something more sensible, it couldn’t be more work than keeping the things. The turves were dug up and piled, upside-down, to compost. I now have three main walking surfaces in the garden. The short stretch that bears the most traffic is slabbed. The other main paths are all woodchip and across some of the beds I have walking boards.

Woodchip is a great path material for several reasons. It is particularly high in carbon which makes it a very infertile medium. Woodchip should never be dug into the soil or, in my opinion, used as a mulch on top of beds, since the soil bacteria pull nitrogen out of the soil to help them break down the carbon, robbing your plants of essential fertiliser. Using it on paths turns its downside into a virtue. If plants do seed into a bed of woodchip, its soft, granular nature means that it is very easy to hoe them off. If you have ever tried to hoe gravel you will understand what a benefit this is. Finally, it is usually a cheap, easily available material. We just get the City Council, who produce mounds of the stuff and are delighted to get rid of it, to drop us off a heap every year. This year’s load turned up last week.

To make the woodchip paths, I dug out about a foot of soil and used it to build up the beds. I lined the bottom of the trenches with any cardboard and bits of old board that I could scavenge, but didn’t worry about this where nothing came to hand. Then I simply filled them with as much woodchip as I could lay my hands on. They have to be hoed in the spring and topped up about once a year, but neither job is urgent and they can be done whenever there is time.

As well as being much less work, woodchip paths are far more robust than grass ones, something I’m appreciating in the current wet weather as the grass paths are trampled to mud while the woodchip ones show no ill effects at all.

Walking boards are even simpler. I only really use them in the annual parts of the garden as there is no problem in stepping on the soil in the perennial parts. They are simply boards laid down on top of the soil to make a path. They serve two main purposes: stopping soil compaction and acting as slug traps. If you turn over any piece of wood lying on the ground you’ll see what I mean: the slugs retire there during the day and can be collected easily. The boards also provide habitat for beetles and centipedes which eat slugs and their eggs, so the slimy molluscs get a double whammy.

Here’s the end result. The forest garden has been thoroughly put to bed for the winter, with a mulch of leaves on the growing areas and a new layer of woodchip on the paths.