Category Archives: Species

King’s spear (Asphodeline lutea)

I first came across king’s spear (Asphodeline lutea) at the Plants for a Future site down in Cornwall, where I was captivated by the beauty and sweet taste of the yellow flowers. It only remained to try to answer my usual question: yes, but will it grow in Aberdeen?

I had almost come to the conclusion that the answer was no and king’s spear was coming close to joining my failures list. It has grown quite happily for around five years, surviving temperatures of down to minus fifteen centigrade on one occasion, but there had never been any sign of those flowers. This year, however, perhaps sensing impending doom if it didn’t get its metaphorical finger out, it has flowered gloriously.

king's spear flower

King’s spear’s flowers are sweet and mild. They are borne on huge flower spikes, with the individual flowers lasting only for a very short while, which means that they lend themselves well to regular picking for salads. Their main drawback is that it also means that they don’t store well and they are best used the same day that they are picked (which is not usually difficult). New flowers are opened the next day so little is lost decoratively.

It has an unusual growth pattern, presumably linked to the climate in its native Turkey. It comes into growth in the autumn and grows happily through the winter. Cold weather slows it down but doesn’t seem to stop it. It then flowers in spring and summer (mine started in mid May and looks like it will make it through most of July), before going dormant for a period in late summer.

There are two other edible parts. The leaf bundles can be harvested during the growing season. The tougher ends of the leaves are trimmed off and they are boiled, rather like leeks. The flavour is mild and pleasant and they make a welcome winter vegetable. The roots are also listed as edible: apparently the ancient Greeks used to mash them together with oil and figs. I have tried them and all I can say is that (a) the ancient Greeks must have had more time on their hands than I do as they are very fiddly and (b) I can see why they used the oil and the figs – probably to disguise the flavour.

A. lutea growing in the Winter Gardens, Duthie Park, Aberdeen

King’s spear growing in the Winter Gardens, Duthie Park, Aberdeen

King’s spear is very easily propagated by dividing the roots and it is widely available since it is used as a decorative plant. For me it only remains to find out whether its flowering this year was down to the very mild winter and spring or if it is now going to be a regular feature.

UPDATE. Since this was written, king’s spear has flowered most years, although not always. I have also discovered that the best part to eat is the whole immature flower spike – although then of course you don’t get the flowers.

Chufa / tigernut

The Egyptians appreciated their sedges. One of them is papyrus, from which they made the world’s first paper. Another is chufa (Cyperus esculentus), also known as yellow nutsedge, the best of the very small number of edible sedges. Dried chufa tubers, or tigernuts as the marketing people would have us call them, have been found in pre-dynastic Egyptian tombs from around 6,000 years ago. It is surprising that the rest of the world has taken so long to appreciate their qualities.

This year I decided to see how they would cope with growing in Scotland. C. esculentus comes in a number of subspecies, some of which are adapted growing in the tropics and some of which range as far north as Alaska, where they are considered a serious invasive weed. The variety that I got was a southern one, which probably meant that the yield wasn’t as high as it could have been but did eliminate any potential weed problems as the plants are completely killed by our winters and rely on human help to overwinter the tubers.

Chufa tubers have a notoriously poor germination rate – probably a deliberate strategy by the plant to hedge its bets by spreading sprouting times – but I managed to get a good proportion started by soaking them, then giving them bottom heat in a propagator early in the year. These were then grown on the window sill until the soil warmed enough to plant them out. I grew them in pots to guard against the invasive root systems that growing guides are full of dark warnings against, but in the event I found that they produced compact root systems with the tubers all held close to the base of the plant. They stood up to a few mild frosts but with the first hard frost of November the tops died off and it was time to have a look at my harvest.

Cyperus esculentus

My verdict? Chufa tubers are delicious. Raw, they have both the texture and the taste of coconut. They cook very quickly, which gives them a slightly more floury texture and a very pleasant taste inside, but more surprisingly they keep their crunch no matter how long you cook them for, which makes them a great textural addition to winter stews. Chufa tubers are also used to make a drink called horchata de chufa, for which they are grown in some quantity in Spain. The Spanish generally add sugar and spices, but to my taste it is at its refreshing best if you make it simply by blending some tubers in water and straining to take out the bits.

Chufa tubers are very nutritious, with twice the starch content of potatoes and plenty of vitamins and minerals. They also store very easily: once dried they keep indefinitely. The only remaining question is productiveness. My yields were low, but I gave them more space than they needed (50cm apart) so things could be improved by planting them closer together. Even if they turned out not to be very productive I would still grow some as I am very taken with the flavour and texture. My only problem is whether I am going to be able to hold off from nibbling on them long enough to have a supply to plant next year.

Chufa on sale in Burkina Faso. I didn't get this many.

Chufa on sale in Burkina Faso. I didn’t get this many.

Alpine strawberry

It’s difficult to start writing about alpine strawberries without straight away making comparisons with the regular, hybrid strawberry (Fragaria x ananassa), but try to put the big brother out of your mind for a moment. Alpine strawberries are different: the taste is different, the growing requirements are different, the season is different. Alpine and hybrid strawberries are not alternatives to each other, they are simply different crops.

Essentially, alpine strawberry is wild strawberry (Fragaria vesca), but with one crucial distinction. You may have come across wild strawberries when out on a walk: shy, elusive creatures, they tend to peek out from between other plants so the pleasure of their fruit has much to do with the thrill of the hunt. When you do find one though, the reward is sweet – and bursting with intense flavour. The temptation to try to transfer the experience to the more reliable setting of the garden is overwhelming, but the results are mostly disappointing. Adapted to scrambling around in a Darwinian tangled bank, show a wild strawberry a piece of ground all of its own and it tends to go a bit, er, wild. Fruiting is forgotten as they send out a thicket of runners in all directions and you realise that you have created a monster.

wild strawberry

Alpine strawberries are simply wild strawberries that don’t produce runners, but from this small change a number of differences flow. Because they don’t put their resources into vegetative reproduction, all their energy can be channeled into fruiting. The alpine strawberry season usually starts around May or June and lasts through to the first frosts. They are also much better behaved in the garden, forming neat little mounds about a foot in diameter that are very useful for lining paths so that you can browse your way along.

Finally, they are much easier to breed from seed. It’s not that wild strawberries won’t grow from seed, but since one clone will fill an entire bed it’s much harder to do comparisons of the results. As a result, alpine strawberries have been bred into a number of named varieties, selected for size, shape, flavour and colour. You can choose between ‘Mignonette’, ‘Baron Solemacher’, ‘Scarlet Wonder’ and ‘Pineapple Crush’.  ‘Alexandria’ is generally reckoned to be the best for the UK. One of my favourites, ‘Blanc Amélioré’, has actually reverted to a runnering habit, although it used to be a true, non-runnering alpine. Best of all, alpines grow easily from seed and indeed will self seed themselves around your garden, so you can do a bit of amateur plant breeding and create your own unique strawberry, perfectly adapted to your garden and your tastes.

alpine strawberry flower

alpine strawberry flower

The flavour of alpine strawberries is sometimes described as ‘strawberry and vanilla’. They don’t develop their full flavour until they are really ripe. Picked when they have just turned red they will be disappointing: you have to wait until they develop a darker colour. Picking the white varieties can be tricky as there is practically no colour change, but there is a shape change as they sort of puff up that you can learn to recognise. The idea behind white fruits is that the birds aren’t meant to be able to find them, but in my garden the birds don’t seem to have got the memo, at least in the case of whitecurrants and yellow raspberries. White alpines are an exception: the birds really do seem to leave them alone. I think of them as sweeter than the reds but possibly just because they get a chance to stay on the plant for longer.

alpine strawberry fruit

alpine strawberry fruitBy now, I can’t avoid those hybrid strawberry comparisons any longer. The most obvious first: alpine strawberries aren’t so big. If you are looking for huge bowlfuls laden with cream or want to make jam, then hybrids are the way to go. But alpines make up for it in a lot of ways. They aren’t such heavy feeders, there is less work picking off runners, they are less prone to diseases and last for longer, they will tolerate a bit of shade (but expect later and smaller crops) and their cropping season is far longer. In practice, I grow both. A small patch of hybrids gives a high summer treat, but the alpines are my mainstay, yielding a handful of seriously tasty fruit every week of the summer. The wild strawberries, on the other hand, are just a pest and I’ve finally decided it’s time for them to go from the garden to make way for better behaved, more productive crops, restored to their rightful place as an occasional foraged treat, running free in the wild.

colour riot - late summer fruits

colour riot – late summer fruitsAnother useful quality of alpine (and wild) strawberries that you won’t find in the hybrids is that, left in a sunny place, they will self-dry and thereafter keep forever. The smell while they are drying is absolutely amazing: if you want to scent a room, forget incense and oils – just leave a few alpine strawberries sitting on the windowsill.

If you want to grow alpine strawberries, there is a good range of varieties available from The Strawberry Store and plenty of seed companies carry one variety or another. Be careful when buying seed from amateur suppliers though. At least one seller on eBay illustrates their ‘white wild strawberries’ with a picture of a pineberry, which is a variety of hybrid strawberry. If this is what they are selling, then like all hybrids it won’t come true from seed but will give very uncertain results. You can also propagate alpines by dividing the clumps, which will of course give new plants that are clones of the original.

Currants in the forest garden

Currants of all kinds should be naturals for the forest garden: they are natural inhabitants of the forest edge with a long history of use as a fruit. And indeed they can be, but only if you don’t get too carried away with the idea of ‘natural’. Getting the best out of currants – often getting anything out of currants – depends on some distinctly artificial pruning and netting.

redcurrants

Currants are in the genus Ribes, which includes blackcurrant (R. nigrum), gooseberry (R. uva-crispa) and redcurrant and whitecurrant (both R. rubrum). There are also around 150 other species, and so plenty of room to experiment, but none of them have ever become as popular as the traditional three. Jostaberry  is a blackcurrant/gooseberry cross, but since it basically tastes like blackcurrants but makes a bigger plant that produces less fruit it is difficult to see the point in growing it. Worcesterberry (R. divaricatum) is like a gooseberry with smaller fruits and bigger thorns but has its fans as a generally trouble-free plant with tasty fruit.

The biggest trouble with currants is that the birds like them at least as much as we do and will strip them before they are ripe, especially the red and white ones. Picking the fruit before the birds get them yields unpleasantly acid fruit which are mind-blowingly tedious to pick. Netting the bushes to keep the birds out transforms things, with luscious fruits that can be picked by the bunch once the whole thing has ripened up instead of carefully picking off the ripest ones. Bunches of currants also keep for far longer than individual fruits that have been torn from the stem and they are great fun to eat by stripping a bunch into your mouth by pulling it through your teeth.

Red, pink and white currants

Red, pink and white currants

This means that there’s an argument for growing your currants in a group as while you can certainly net individual bushes it’s more efficient to net a whole lot together. In my case, there is a tall fence down the southern boundary of my allotment, so I’ve planted all along it with currants as they will tolerate a degree of shade (in warmer climates, they positively require it). The pesky fence then serves some useful purpose as I have put in hooks along the top of it and can attach a net that goes over the whole lot.

netted currants

The other bit of cultivation that helps hugely with currants is pruning. Blackcurrants fruit mostly on one-year-old stems, so if they aren’t pruned the yield drops off rapidly as the bushes age. Pruning of established plants consists of taking out the oldest third of the shoots every year. It’s a good idea to take out weak, drooping, crossing or particularly crowded stems at this point too. Pruning can be done at the same time as picking the fruit or it can be left until winter (which allows the plant to store more of the nutrients from the shoots).

Pruning red and white currants is the exact opposite of blackcurrants. They fruit largely on old wood so pruning consists of taking out a proportion of the new growth in order to persuade the plant to put more of its resources into its fruit and less into growth. Winter pruning is limited to taking out very old or diseased growth: the main prune is done in early summer when the new growth is pruned back to two or three buds per shoot. The growth the next year will go in the direction that the top bud is facing, so by choosing where you prune you can steer the growth of the shoot. Gooseberries are pruned in the same way, aiming for an open structure that allows air and sun in so that the bushes don’t get mildew.

All currants are high in pectin so they make good jams and jellies and can also be added to other jams like raspberry and strawberry to help them set. They also freeze well and keep a lot of their texture when they are thawed out again. You can dry them if you have a drier, although you won’t get the dried fruit sold as ‘currants’ – they are actually a kind of grape.

Shocking shiitake

It isn’t only plants that we get from the forest garden – it produces a regular supply of mushrooms too. I’ve experimented with growing a wide range of fungi over the years, but for me one really stands out from the others as providing a good supply of produce for the work you put in, and that’s shiitake (Lentinula edodes), which has one secret power that the others don’t.

shiitake

Shiitake is a wood-rotting fungus that is grown on logs: in Britain beech, oak and birch are particularly suitable. Its advantages over other such fungi include that it is a strong grower, quickly colonising its logs and outcompeting the other, less useful, fungi that inevitably turn up and make a bid for complete log domination. It also helps that it is a tasty, nutritious mushroom that is easy to preserve.

Since I work as a forester, I get occasional supplies of the freshly cut logs that are needed for growing shiitake. I quickly order some mushroom spawn (the fungus grown on bran or on softwood dowels) from Ann Miller’s Speciality Mushrooms, which happens to be just up the road but which is behind most suppliers of mushroom spawn in the UK. The spawn is put into holes drilled in the log and sealed with wax (there’s an excellent how-to video about the process on Youtube).

As the fungus colonises the log, I see wedges of white colour appear at the end of the logs as the mycelium works its way up and down the vessels in the wood. After a while these fill in with a chocolatey brown colour which indicates that it is ready to fruit. It also develops a wonderful mushroomy smell. It’s at this point that you can use the trick that makes shiitake so useful. Most wood-rotting mushrooms fruit all at once, giving you a famine followed by an unmanageable glut. This was my experience with oyster mushroom: I would have one week a year eating oyster mushrooms with everything, then back to nothing. In addition, since mushrooms give little notice of when they are going to come out, it is quite possible that you will be away for a few crucial days and come back to find nothing but a rotting mess and feasting slugs. The difference with shiitake is that you can reliably induce individual logs to fruit, as and when you want them.

shiitake mycelium above inoculation holes

shiitake mycelium above inoculation holes

The process for this is known as ‘shocking’, as you are basically trying to give the fungus a fright. First the log is given a sharp rap at either end with a lump hammer, then the whole thing is plunged into cold water for two days or so. Many internet sites will tell you to use iced water but this seems rather wasteful to me as they always fruit quite reliably after being dunked in my (very small) frog pond. Theories abound as to why this treatment actually works. The way it was explained to me was that you are messing with the mushroom’s mind, trying to make it think that its log has fallen out of the tree in an autumn storm and that it needs to reproduce quickly.

Whatever the reason, soon after you take it out of the water you will notice little ‘initials’ appearing through the bark. Over the course of a week or so these swell up into the full-size fruiting bodies. The challenge during this time is to keep it in a cool, moist place away from slugs and snails, which will travel for three days without carrying water at the merest sniff of a shiitake mushroom. I used to swaddle mine in horticultural fleece, which kept the humidity up and the slugs out, but it was awkward and not entirely reliable. Nowadays I put them in my shed, stood up in a plant saucer with a little water in the bottom. This creates a defensive moat and at the same time helps to keep the log wet as fruiting will stop if it dries out. So far this method has been completely reliable. For once I have managed to get on a regular schedule with shocking my logs, doing one a week, and we have had a continual supply of them since May.

Initials

Initials

Shiitake are a versatile and delicious mushroom that can be used in all sorts of ways, so I’ll just share my one favourite way of cooking them with you. If you cut them into thin strips (just a few millimetres thick) and fry them, they develop a texture and even a taste reminiscent of crispy bacon. Instead of putting them in dishes like pasta where the flavour can get a bit lost, I will often cook them this way and put them over the top instead.

Finally, another of shiitake’s super-powers comes into play with any that don’t get eaten in the first few days. Shiitake self-dry incredibly easily if left in any reasonably well ventilated place. They will then store for years but rehydrate very nicely when water is added. I particularly like them in miso soup, where the soaking water can be added to the stock.

Incredible shrinking shiitake

Drying shiitake

Of course, you don’t need a forest garden to grow shiitake, but it is a very good match as there are plenty of damp, shady places where you can leave the logs between fruitings. They can usually be refruited after two months rest and are said to last for two or three years, but some of my big beech logs have been going for eight, so I suspect it depends a lot on the size and species of the log.

Eating dog’s tooth violet

If you were designing a new crop for forest gardening, you might decide you wanted a starchy bulb rather than yet another leaf or fruit producer. Ideally it would be ready early in the season, before all the other roots. It would be nice if the bulbs tasted good, stored well, were a decent size and weren’t fiddly to prepare. Needless to say, it would have to grow in shade. It would also be handy if it was simple to propagate, maybe by dividing and self seeding modestly. While we’re at it, why not give it beautiful early spring flowers too?

Erythronium 'Pagoda'

Erythronium ‘Pagoda’

As is so often the case, nature has got there ahead of us, in the form of the dog’s tooth violet (Erythronium). The common name is a bit misleading as erythroniums are no relation whatsoever to true violets (Viola species), but the ‘dog’s tooth’ part is clear: the tapered white bulbs look like the canines of some monstrous prehistoric hound – not one I’d want to meet on a dark night. There are a number of species you can grow, such as E. americanum, the trout lily, E. japonicum, katakuri, or E. dens-canis, the European dog’s tooth, but the best one to grow for eating, due to its larger bulbs, is the hybrid cultivar ‘Pagoda’. (All the above species are edible, plus many more, but I can’t guarantee that the whole genus is: see Plants for a Future for a list of species.)

Erythroniums have an unusual growth habit: they only ever produce two leaves, which die down in June or July having produced one or hopefully more bulbs. A bulb is a wrapped-up plant, safely packaged and ready to go for the next year. The multiple layers of an onion bulb are the future leaves, while the little dense bit at the base is the stem. The tough outer layers are more leaves, modified to seal in moisture and keep out pests. With only two leaves, erythronium bulbs are noticeably different from this standard. They are long and narrow and have no outer skin, making them ivory-white, easy to prepare and a little prone to drying out if you aren’t careful with storage.

 

Erythronium bulbs

The leaves and flowers are said to be edible, but if you eat the leaves you’ll be missing out on the main course, which is the bulb. They don’t have a strong taste, which makes them useful as a staple. My favourite way of cooking them is to slice them thinly across and fry the discs. They go chewy and sweet, a bit like plantain chips. Another way of frying them is to make chips (in the British sense). The smaller bulbs are just the right size already; the larger ones can be sliced in half or quarter. They are also good boiled and excellent in stews. It’s not something I’ve tried myself, but according to Plants for a Future the European dog’s tooth is dried to make flour and used in making cakes and pasta. (Another useful piece of information from PFaF is that large quantities of dog’s tooths have been known to be emetic. I haven’t experienced this but, as ever, it is a reminder that you should only introduce yourself to a new food gradually.)

It’s a good idea to harvest dog’s tooth bulbs before the foliage has completely died down as they are then easy to find and you don’t have to dig around for them. They dry out easily so if you are storing them for a long period of time they need to be kept cool and moist. I get round this by only eating them in season. They are usually ready by the start of June so they fill the gap in the potato season nicely. I dig them up, take a proportion for eating and replant the rest as they will keep quite happily in the ground for the rest of the year.

Such an early harvest gives an opportunity to use the ground for something else for the rest of the year. This could simply be weed control as you can hoe over the top of the dormant dog’s tooths so long as you have planted them deep enough. Alternatively you could sow a green manure or a quick crop like mustard greens or intercrop it with something like wild strawberry that uses the later part of the year and won’t interfere too much with the erythronium’s growth. Like most bulbs, dog’s tooths are adept at punching up through a thick layer of mulch, so I give mine a thick mulch of leaves in the autumn to both feed and protect them.

Growing and eating ground elder

What did the Romans ever do for us? Well, they introduced ground elder…

To many gardeners, this one fact alone is probably enough to condemn the entire 400-year Roman occupation of southern Britain out of hand. Ground elder (Aegopodium podagraria) is a perennial vegetable with a bad rep. Its combination of propagation by seed and by masses of spaghetti-like underground runners makes it an almost unstoppable spreader and very difficult to remove from ground once it is established. In parts of Australia and North America it is legally controlled as an invasive weed. All this adds up to a plant that is considered by most gardeners to be one of the worst weeds that there is.

ground elder

Of course, there is another way of looking at ground elder’s ebullient nature: it’s an edible plant that is very productive, grows strongly enough to outcompete any weeds, tolerates shade and poor soils and is found almost everywhere. One big question remains though: does it taste any good?

Many people will have read that ground elder is edible and nibbled a leaf speculatively, perhaps wondering whether they could eat the damn thing into submission. The result is usually not good. Mature ground elder leaves have a strong, unpleasant taste that invades the mouth and won’t let go, rather like the plants in a plot of ground. It’s a shame that this puts so many people off, because, picked and prepared properly, ground elder is actually very nice indeed.

The trick to ground elder is to pick only the youngest, freshest leaf shoots – before the leaf has even unfolded. At this stage they have a glossy, translucent green colour that helps you to pick them out. It is the petiole or leaf stem more than the leaves themselves that constitute the vegetable, so pick them off as low down as you can manage.

ground elder shoots

The simplest way to prepare ground elder is to fry it in olive oil until the leaves have wilted and the stem is tender and serve as a side dish. Even in more complicated dishes, frying is a good way of bringing out its flavour – as in this recipe.

Pernicious pasta (1 serving)
100 g dried linguine
half an onion, finely chopped
garlic
a few mushrooms, finely chopped
5 nettle tops
10-20 ground elder shoots
50-100 ml double cream
1 tsp stock powder
finely chopped herbs

Break the linguine in half so it is about the same length as the nettles and ground elder shoots (if the ground elder stems are particularly long, cut them in half too). Cook the linguine until nearly al dente and drain. For the rest, use the biggest frying pan you can find as you want to fry rather than steam the ingredients. Fry the onion or other alliums in olive oil for a couple of minutes. Add the garlic (if using wild garlic, chop in near the end) and mushrooms (ideally shiitake, otherwise cultivated) and fry for a couple of minutes more. Then add the nettle tops and fry for 5 minutes or so, followed by the ground elder stems and another 5 minutes frying. Add the linguine and stir. Then add the cream and a little water, a teaspoon of bouillon or other stock powder and fresh, finely-chopped herbs such as parsley, wild celery, Scots lovage and sweet cicely. Cook gently for a couple more minutes and serve.

ground elder pasta

If you want to grow ground elder, the simplest advice is probably – don’t. It is so common that it may well be easier to find a patch near your garden that you can forage from. You could possibly even manage it gently for greater production. If you use foraged ingredients then it goes without saying that you should wash them well, make sure they haven’t been sprayed and make sure you have positively identified them.

If foraging isn’t an option, or you’re feeling particularly brave, and you want to give growing it a try, you will have to bring in the big guns in terms of containment. You need a larger patch than can be contained in a pot sunk into the ground, so choose a bed and accept from the start that it will spread through the entire bed. The bed has to be bordered on all sides by GE-proof barriers, which is to say short mown grass, paving without lots of cracks or a woodchip path that is hoed regularly. All these barriers should be a metre or more wide as the runners can go a good distance underground.

You want to cut the whole stand down as soon as it starts to flower, both to encourage new shoot production and to prevent seeding, so you can’t mix it in with anything that won’t take being cut down in late spring. One option is to grow ground elder in a ‘thug bed’ with other strong growers such as wild garlic. The bed should be in fairly deep shade under a tree or wall. It is possible to get variegated ground elder, which is not quite such a strong grower. If you have ground elder in your garden, invited or uninvited, it is very important not to put fragments of it into your compost as this will spread it into other areas. I have a ‘toxics’ compost bin where persistent weeds like docks and ground elder and potential disease spreaders like potato haulms go for extended treatment.

ground elder

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.

Wasabia japonica

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

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

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 flower heads of lady’s smock (Cardamine pratensis, also known as cuckoo flower), a native cress growing in damp and shady places. The leaves also have horseradish flavour which is stronger than that in the flower heads.

Lady's smock

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.

Finally, Turkish rocket (Bunias orientalis) root has also been recommended as a horseradish substitute. It has a pleasant, spicy flavour but seems to lack the characteristic kick in the sinuses of horseradish.

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.

rhubarb flower stems

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.

rhubarb flowers

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.

Since a flower head will contain some stem and therefore some oxalic acid no matter how carefully you prepare it, it would be a bad idea to consume excessive amounts of them. This is also true of the rhubarb stems that are more normally eaten.

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

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.

Wild garlic

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 leaves into salads: whole leaves are a bit strong to eat in bulk but chopped roughly and mixed with other leaves they are delicious. Layering a few leaves into a sandwich works well too. For some seriously local food, you can try using it to supply the garlic flavour in broad bean hummus.

However, if its garlic flavour were the only thing that wild garlic had going for it, 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. The bulbs are also usable once the leaves have died down, but they are not as good as the bulbs of cultivated garlic and they don’t store very well once lifted. And of course, if you eat all the bulbs then you don’t get the other parts. That said, if you have a good supply of them you might want to try the recipe for pickled wild garlic bulbs that can be found – with 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

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 – 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! If you are in Scotland, don’t forget that it is legal to pick leaves, flowers and seeds for your own use without the owner’s permission but not to uproot a plant (e.g. by transplanting bulbs) or to harvest commercially. If you want to do either of these you will have to ask the owner.

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 picking lots of leaves 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.

wild garlic 02

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

In North America, the name ramps has transferred itself to a similar-looking plant, Allium tricoccum, also known as wild leek. It’s a fascinating piece of convergent evolution. The two species are actually rather distantly related within the Allium genus, but by adapting to the same woodland niche they have come to be very similar in both looks and behaviour. Both are spring ephemerals, coming up and dying down early to make the most of the spring sunlight before the trees leaf up. Both carpet the ground and have broad, delicate leaves, adapted to capturing as much light as possible and dropping the usual allium adaptations to drought and strong sunshine. Despite this there are differences reflecting their divergent ancestry. The North American ramps has shallower bulbs than the Eurasian and the whole plant is more commonly used rather than just the leaves. The leaves and bulbs become tough and inedible and start to die down once the plant starts flowering, unlike A. ursinum, in which leaves and flowers occur together.

Further reading: Forest Gardening; Real Spring Onions.