Growing and eating silverweed

Silverweed has a long history as a cultivated crop. It was sufficiently important, in the landscape-scale agro-ecology of the pre-colonial Pacific North West, that access to good patches was controlled by law. Closer to home, Alexander Carmichael says in the notes to the Carmina Gadelica that silverweed root (brisgean) was much used in the Gàidhealtachd before the potato was introduced. He says that it could be traded, ‘quantity for quantity’ with corn and meal, suggesting that it was equally valued nutritionally. It was considered palatable and nutritious and eaten boiled or roasted or dried and ground into meal for bread and porridge. I mostly eat it boiled and find that it has a rich, creamy taste and texture.

One eye-catching claim made by Carmichael is that at Lag nan Tanchasg in Paible, North Uist, ‘a man could sustain himself on a square of ground of his own length’ by growing silverweed. Unfortunately he makes no mention of cultivation methods, but I suspect that he is talking about a lazy bed system, in which a raised bed is heavily mulched with seaweed. This would make sense both as a way of growing heavy yields of, well, anything, on Uist (and was later used there for growing potatoes), and also because silverweed is well adapted to growing on the seashore and is often found there. Like many species adapted to growing on shifting sediments, it spreads strongly via runners, which help it to bind the soil together and adapt quickly to disturbance. It’s a habit which has helped it adapt to other, novel habitats, such as the frequently-disturbed, heavily-salted margins of roads.

Variation between clones: silverweed…

…and not-so-silver weed

It’s also a habit which makes it, as anyone who has tried will know, difficult to replicate past cultivation methods in an ordinary garden. It will take over any veg bed it is planted in in short order. It will also naturalise happily in grass, but then it becomes very difficult to dig out the starchy roots which are its main edible part. A further complication, if anyone was really serious about adapting this plant to cultivation, is that it’s hard to maintain and breed separate lines of a plant that is hard to contain as an individual even in a pot, never mind in a patch of soil.

This might explain why, despite having been interested in silverweed ever since I first tasted its roots, I haven’t made much progress in fitting it into my garden. However, I did make one useful discovery recently which should make the task somewhat easier. I have a number of individual clones, collected from around the country, which I keep separate by growing in buckets (escaping from a bucket is nothing to this Houdini among plants, but you can thwart it by winding its runners around inside the rim of the bucket, making sure they never touch the ground). One winter I tipped out one of these buckets, and discovered that the thickened roots had almost all formed right at the bottom – making it easy to nip off the best ones to eat. I then put some compost in the bottom before putting the whole mass back in on top. They respond well to this treatment, and also become more willing to produce seeds, which I plan to use to start new pot-colonies.

brisgean
seeds

It’s not really in the spirit of forest gardening, in which the plants are meant to be more integrated than this. It’s also a challenge with other shifting-sediment plants like asparagus, which rely on their environment to deal with competitors and are intolerant of any competition. However, I can picture an analogue of the lazy bed, with a well-edged raised bed, regularly topped up with the abundant compost produced by a forest garden. This wouldn’t have the bottom-of-the-bucket effect but would probably create a soil loose enough to be dug easily.

Incidentally, I haven’t been following my usual practice of giving Latin names alongside the English ones in this post. This is because the naming of silverweed is, frankly, a mess. It’s an aggregate species which can be divided into many or lumped into one according to taste and fashion, and systematists can’t even agree on which genus to place it in. It is (probably) called Potenialla anserina today, but the genus name Argentina is also commonly used.

Silverweed flowers by S. Rae from Scotland, UK, CC BY 2.0 via Wikimedia Commons

Honey under ground
Silverweed of spring.

Honey and condiment
Whisked whey of summer.

Honey and fruitage
Carrot of autumn.

Honey and crunching
Nuts of winter
Between Feast of Andrew
And Christmastide.

Carmina Gadelica, from translation edited by CJ Moore, Floris Books 1992 p366. Thanks to Alison Tindale of the Backyard Larder for putting me on to this reference.

Saltbush (Atriplex halimus)

I first came across saltbush (Atriplex halimus) at the Plants for a Future site down in Cornwall. I loved the salty taste of the leaves and spent many years trying to establish it in Aberdeen. Unfortunately we are on the edge of its range here and I lost a succession of plants, usually over winter. I think I have finally cracked it though, as my latest plant has survived many years, including temperatures down to -11°C this winter. In common with many Mediterranean plants, its real enemy is not so much winter cold as winter wet, so the key to survival is giving it a really well-drained spot. I have mine at the apex of a raised bed, sheltered from the rising sun in winter to minimise frost damage. Planting early in the growing season helps to give the plant the best root development by the time winter comes. If you acquire a plant in late summer, autumn or winter, keep it inside until you can plant it out in spring.

You might want to grow saltbush even if you weren’t interested in eating it, as it’s a very attractive plant. It eventually grows to be a small shrub with silvery-grey leaves. These leaves are the edible part, with a salty tang that is nice mixed into a salad. The saltiness of the leaves does seem to vary with the time of year and the amount of salt in the soil – at least it seemed to me that they were saltier after I mulched my plant with seaweed one year. The best way to pick the leaves is to nip out whole growing tips. This gives you the tenderest leaves and encourages the production of more. It also helps to keep the plant compact and stop it getting leggy. A cultivar called ‘Cascais’ is worth getting hold of as it has larger leaves and shorter internodes than the wild type, giving you more leaf and less stem.

One advantage of saltbush is that it is very easy to grow from cuttings, which means that you can take a backup copy, as it were, if you’re worried about losing your main plant over winter. In the UK, I can send a cutting to anyone interested in giving it a go – see my seed list for details.

Forest garden seed list 2020-21

It’s taken a while, but my complete list of seeds (plus a few tubers, bulbils, etc) collected in 2020 is now ready. It’s longer than ever, with over 70 species listed. As usual, I don’t charge for seeds, but am open to swaps (see my Wish list), happy to receive donations and delighted to help out anyone willing to pay it forward by supporting the open source seed community in general.

You can find the list here.

Spinach vine (Hablitzia tamnoides) seeds

My top 30 forest garden plants

One of the questions I am asked most often about forest gardening is which plants to start with. I find this a hard question to answer for a number of reasons. One is that the key to a forest garden is diversity, so the answer I really want to give is all of them, which I realise isn’t very helpful. The second is that it’s a very individual matter, depending on the gardener’s climate, site, taste buds and access to plants that can be foraged. For instance, I don’t grow brambles (blackberries), since I know of several spots within cycling distance where I can pick to my heart’s content – but if I couldn’t get them wild I would most certainly grow them.

Despite all that, the question keeps coming up again, so here – with all the caveats above and in no particular order – is my personal top 30, of plants that are productive, easy to source and easy to grow. It might not be the same as yours, but it’s a place to start.

Wild garlic (Allium ursinum)
Very shade tolerant, very reliable and very productive once it gets going, wild garlic is available from February to June and provides a garlic flavour when raw or a bulk vegetable with an oniony taste when cooked.
Growing and eating wild garlic

Kale (Brassica oleracea)
With year-round leaves and delicious, nutritious flower shoots in spring, kale is one of my most reliable pot herbs. Both biennial and perennial varieties are available.
Daubenton’s kale – growing and cooking
Perennial kale breeding

Chives (Allium schoenoprasum)
There is a huge number of leafy alliums that can be grown in the forest garden, but this traditional one is still one of my favourites. I use the flowers as much as the leaves, cooked as much as raw.

Perennial leeks (Allium porrum)
Complementing annual leeks nicely, perennial leeks can be bred quite easily from traditional annual varieties or grown from bulbils produced by cultivars such as Babington leek.
www.facebook.com/scottishforestgarden/posts/2767925186556620

Celery (Apium graveolens)
Half way between a herb and a vegetable, hardy celery provides stems, leaves and/or flower shoots at almost any time of year. I never use it on its own but to add flavour and bulk to pot herbs, soups, stews and stir fries.
Hardy celery

Sea beet (Beta vulgaris maritima)
The ancestor of sugar beet, beetroot and chard, sea beet is hardy, nutritious, tasty and productive. I use leaves in autumn, winter and spring, moving to the immature flower heads (steamed and then dressed with sesame oil, soy sauce and lemon juice) in summer. Just remember to let some of them produce seed as it grows better as a biennial than as a perennial.
leaf beet
https://www.facebook.com/scottishforestgarden/posts/2390524570963352

Giant bellflower (Campanula latifolia)
Giant bellflower provides leaves, shoots and roots and has the advantage of being more shade tolerant than most bellflowers.

Miner’s lettuce (Claytonia perfoliata)
A mild-tasting salad leaf, miner’s lettuce needs some ground disturbance to keep seeding itself. Once established, it will pop up wherever there is a gap.
Claytonias – miner’s lettuce, wood purslanes and spring beauties

Fawn lilies (Erythronium)
A useful shade-tolerant starchy root crop. The cultivar ‘Pagoda’ is large and productive and very pretty too.
Eating dog’s tooth violet

Potato (Solanum tuberosum)
Wait, what? Tatties? Yes, spuds are perennial vegetables that grow well in the organic-matter-rich soil of a forest garden (not in deep shade, obviously). Using blight resistant varieties like the Sarpo family and growing new ones from seed allows you to grow them more like a perennial crop, less like an honorary annual.

Alpine strawberry (Fragaria vesca)
Alpine strawberries are wild strawberries that don’t produce runners. They are thus more manageable and easier to select good varieties from. Will self seed in the garden.
Alpine strawberry

Raspberry (Rubus idaeus)
My favourite soft fruit, and a natural inhabitant of the woodland edge.

Caucasian spinach (Hablitzia tamnoides)
A perennial climber with spinach-like leaves and edible shoots.

Daylily (Hemerocallis)
An easy-to-grow, attractive perennial that likes a sunny spot and produces edible flowers.
Eating daylilies (Hemerocallis)

Shiitake (Lentinula edodes)
Of the many mushrooms that can be grown in a forest garden, shiitake is my favourite – and perhaps the easiest.
Shocking shiitake

Apple (Malus domestica)
A productive and versatile fruit that keeps well into the winter. I use it for cooking, baking and making dried apple rings.
Applemania
In Praise of Pruning

Sweet cicely (Myrrhis odorata)
Of the many carrot relatives with edible young leaf and flower shoots, I perhaps make the most use of sweet cicely, which has a very long cropping season and aniseed-flavoured roots, leaves, flowers and seeds.
Sweet cicely

Poppy (Papaver somniferum)
A feast for the eye, for the pollinators and for the stomach, poppies produce nutritious, oil-rich seeds and pop up everywhere to fill any temporary space in the garden.
Opium poppy

Japanese plum (Prunus salicina)
Japanese plum makes the best fruit leather, is absurdly productive and fruits earlier than traditional domestica plums.
Japanese plums

Parsnip (Pastinaca sativa)
Another one that you might not expect in the forest garden, parsnips self-seed around the place and produce a crop with very little effort.
Self-seeded parsnips

Rhubarb (Rheum)
A very well-known perennial vegetable, rhubarb has both more species and more uses than it is traditionally given credit for.
rhubarb

Currants (Ribes)
Forced to choose between the different currants. I’d probably go for red/white currant, which becomes sweet enough to eat off the stem if protected from birds by netting, and is a secret ingredient in many jams with its high pectin content.
Currants

Sorrel (Rumex)
The sharp, lemony taste of sorrel is found in many plants. Forced to choose, I’d go for garden sorrel (R. acetosa) or buckler leaved sorrel (R. scutatus). Or both.
Sorrels

Linden (Tilia)
Small-leaved lime is my favourite ‘salad tree’. If the growing tips are picked rather than individual leaves it will produce a supply of tender leaves for most of the growing season. Best pruned like a hedge.
Lime greens

Salsify (Tragopogon porrifolius)
Another self-seeding annual, salsify produces an abundance of artichoke-flavoured flowers.
Salsify

Broad bean (Vicia fava)
The bean that fits best into the forest garden system, growing in small cleared patches.
Broad beans

Lovage (Levisticum officinale)
Another source of shoots throughout the growing season, lovage adds an earthy/yeasty/meaty taste to all sorts of dishes.
Lovage, actually

Persian garlic (Allium altissimum)
As well as being a striking ornamental, Persian garlic is a vigorous plant, producing large clumps of mild, garlic-flavoured bulbs, available outside the wild garlic season and easy to preserve by slicing and drying.

Nettle (Urtica dioica)
Nettles can be foraged, but having your own patch allows you to cut them down for repeated harvests. There is even a non-stinging variety!

Udo (Aralia cordata)
An enormous herbaceous perennial, udo produces an edible pith for stir fries and salads and shoot tips for tempura or stir fry, or to add depth of flavour to a leaf sauce. The taste is part citrussy, part resiny.
Growing and eating udo – Aralia cordata

To source any of these, see My seeds or Other suppliers.

Perennial kale breeding

I notice it’s been five years since my last post on perennial kale breeding. Enough time for some progress surely? Happily, yes, and I now have an abundance of seed to share with anyone who wants to join in. I’ve been aiming to produce a population of kales that are mid way between the near-sterile Daubenton’s perennial kale and the traditional biennial kale: that is to say, plants that flower enough to breed from but don’t flower themselves to death. I have been increasing the diversity by crossing all my favourite traditional kales with plants that have these traits.

Not all of the results are finished varieties that I’d want to propagate vegetatively, but all have at least one trait I want to keep in the population. Some of my favourites haven’t flowered yet: these are the ones that I have been able to collect seed from this year. The hands in the pictures are for scale and measure 22 cm. Seeds of all these and a few more are available on my seed list. Please note that they are all open pollinated, so seedlings will show considerable variation – which is part of the fun!

Purple kale tree

This is perhaps my favourite that I have seed for. It is seven years old and still growing strong: the original stem grew to about 10 cm and eventually died, but others have taken its place and it roots itself by layering, Daubenton-style. The leaves are large, tender when young and, of course, purple. Flowering intensity: low. Flowers: white. Some of PKT’s offspring are similar but with even larger leaves and faster growth.

Here is one offspring of PKT that hasn’t flowered yet.

And one that has, imaginatively titled ‘Son of PKT’. It has the same tall growth habit but a leaf shape that might indicate a cross with ‘Cabbagey’ (see below).

Flowering Daubenton’s

This is the most similar to classic Daubenton’s with similar leaves and growth habit, but it flowers every year, with a medium flowering intensity. Not a great kale in itself, but good for breeding off, especially for its strong branching habit and short annual growth which give it a relatively neat, dome-like form.

Deep purple

With deep purple, lobed leaves and a rather straggly growth habit. Hand for scale.

Oak leaf bush

Large, lobed green leaves and a bushy habit. Flowering intensity: high.

Lobed purple

Another of the lobed-leaf group, this time looking like it has Ragged Jack in its ancestry. Strongly branching. Flowering intensity: low.

Cabbagey

Not in fact a single variety, but one original plant and its nearby offspring, all of which I suspect have a cabbage somewhere in their offspring, giving unexciting but mild leaves. With a very straggly growth habit and moderately high flowering intensity.

Tall savoy

Tall, upright ‘kale tree’ growth habit, with somewhat savoyed leaves. Medium flowering intensity.

Big leaf Jack

The flattened winged stems of this variety remind me of Ragged Jack and it has big leaves. Flowering intensity medium-high.

Big green lazy

Not an awful lot to recommend this one, apart from its large leaves. It’s quite susceptible to mildew at this time of year, although the younger leaves that I pick are unaffected. Long, floppy stems that mean that it forms a thicket. Medium flowering intensity.

Nero di Toscana perenne

Three plants arising from a cross between Purple Kale Tree and Nero di Toscana. Need back-crossed a few times to form a true perennial Black Tuscan Kale. All three are very tall, reaching over 2 m in 2 years (too tall in fact – need to breed in shorter internodes). The first flowered strongly this year and, for obvious reasons, this is the one I have seed for. The second flowered very lightly, which would be perfect but unfortunately I only managed to collect a tiny amount of seed. The third (the most NdT-like) has not flowered at all. I have had to give up the site where these were planted but I have taken lots of cuttings, so fingers crossed.

Plant 1
Plant 2
Plant 3
Leaves of 1, 2 and 3 (L to R)

2021 update

The winter of 2020/21 was a cold one in Aberdeen, with temperatures down to -15 degrees C: testing temperatures for a kale. This was great for plant breeding, in that it weeded out the less cold-tolerant varieties, but less good for individual lines.

A majority didn’t make it. My oldest plant of ‘Purple Kale Tree’ died, but another grown more recently from a cutting sailed through. This is often the case with perennial kales. Unfortunately the survivor plant barely flowered this year so I can’t offer seed for a while. The oldest individual plant to survive was ‘Flowering Daubenton’, adding to its list of impressive qualities. The Nero di Toscana crosses also did well, although this might owe more to them all having had to be regenerated from cuttings last year than inherent hardiness. Plant 2 didn’t flower at all, but 1 and 3 did so I have seed from this line for others to experiment with. This year’s to-do list includes sowing some actual NdT in the same bed to do some back-crosses. One purple-ribbed plant both made it through the winter and seeded. It wasn’t one of the ones that seeded last year, so it doesn’t have a name yet. Come to think of it, I might call it Purple Rib.

Another plant, with greener leaves, both came through the winter and is showing impressive mildew resistance at a time of year when many plants get badly affected – but unfortunately showed no inclination at all to flower. Some others which sprouted last year and survived the winter had the opposite problem: they flowered too much to be considered good perennials and were removed from the gene pool. I also decided to get tough with a tendency to straggliness in one group and removed all plants that were too floppy.

You can’t keep a good perennial kale down though, and everywhere where one has died several more have sprung up over the course of the year. I have thinned these to leave the more interesting and sturdy ones and now have nothing to do but wait to see how perennial they are.

Hardy celery

Some plants in the forest garden are just more easy to photograph than others. Aralia spinosa spreads its delicate leaflets in one easy-to-focus plane, while pot marigold works the camera shamelessly. Celery is at the other end of the spectrum. Its sprawling habit makes it hard to get into a single coherent photo, while the fact that it puts on most of its leaf growth in autumn, winter and early spring means that the photography conditions usually consist of low light and wet, difficult-to-focus leaves.
20191031_130639
Those of us who don’t show up so well in photographs, however, can still have lots of other excellent qualities, and celery is an indispensable member of the forest garden cast. That growing season means that celery leaves are available when few others are and its flavour is a welcome addition to winter soups and stews. As with most carrot family plants, it’s the young, tender leaf shoots that are best rather than older leaves. In summer the young flower stems can also be used in dishes like stir fry and the seeds, produced in abundance, make a wonderful aromatic spice.
No matter how useful I find celery at present, I think I have only started to explore its potential as a forest garden plant. The celery I’m talking about is not the familiar shop-bought celery with its large, white, crunchy stems. That can be grown in Scotland, but only with lots of care, watering, feeding and mounding, and preferably a polytunnel. I’m talking about the smaller, leafier varieties variously called wild, herb, leaf, cutting or Chinese celery, which are used more as a leafy herb than as a stem vegetable.
Despite their differences, all these varieties are the same species, Apium graveolens. While the chunkier stem celery was clearly developed far south of Scotland, there’s no reason why a bit of selective breeding couldn’t favour the same qualities within a hardier gene pool, more adapted to a forest garden in the North. That’s what I’m working on in my garden, and celery is already responding.
The first step was to source a wide range of genetic sources. This involved navigating a bit of a minefield of names. True wild celery is Apium graveolens var. graveolens or ‘smallage’. It is a plant of wet, salty ground. Seed sold as wild celery is usually probably not true wild celery but one of the leafy cultivated celeries collectively labelled Apium graveolens var. secalinum, as opposed to the thick-stemmed var. dulce. One group of these are the Chinese celeries, also known as kintsai (which is just an old spelling of the Chinese word for celery, qíncài or 芹菜) or Nan Ling celery. Chinese celeries have generally undergone more selection than their Western counterparts. They tend to be more delicate and more colourful, and not quite so hardy. Western secalinum are called herb, leaf or cutting celery. There’s also a Dutch heirloom variety usually marketed as ‘Par-cel’ or occasionally ‘Zwolche Krul’. It’s a dead ringer for curly-leaved parsely – hence the name – and there’s a lot of confusion on the internet as to which it really is.


Having sown a range of these different kinds, I left them to it for a few years to mix up the gene pool. Celery is biennial so there is a new generation every couple of years. Now everything is well mixed, I’m starting to apply some selection pressures. There are a few qualities that I’m selecting for. Size and vigour are important of course. For stem qualities I’m looking for thickness and solidity. Some stems are hollow while others are fleshy all the way through. A few plants seem to have a degree of perenniality, surviving and growing again after flowering. Hardiness and general adaptation to my garden conditions are selected for by the environment.
You can see some of the variation here, in the range of leaf lengths, thicknesses, colours and solidity. No prizes for guessing which is my favourite one so far.
_MG_6365celery comparison
I haven’t tried selecting for a thickened hypocotl or stem base yet, but that would be the route to an equivalent of celeriac, the bulbous Apium graveolens var. rapaceum.
Although celery is ancestrally a marsh plant mine seem happy in all parts of the garden, including in a moderate amount of shade. In contrast to the traditional celery it needs next to no special care.

Claytonias – miner's lettuce, wood purslanes and spring beauties

The Claytonias are a very useful group in the forest garden, being very palatable species whose natural habitat is woodland.

Claytonia perfoliata, miners’ lettuce, is unusual in the genus in that it is an annual rather than a perennial. It is often grown in greenhouses in Britain as a winter salad, but it is much less commonly found grown outside. It can be difficult to get established as a self-sustaining, self-seeding population, but once you manage it makes an excellent early salad that maintains itself with little fuss. Getting a locally adapted strain might be the key to success: I spent a long time trying it with little luck until I found a population self-seeding itself in the nearby university car park, prospering despite the chemical warfare waged against it by the university’s estates department. Seeds from these plants germinate earlier and grow more vigorously than any that I have ever bought from the seed trade.

Miners’ lettuce is mild-flavoured and succulent so it makes an excellent bulk ingredient for salads. All parts are edible, including the leaves, stems and the unusual-looking large fleshy bract around the flowers. They can also be cooked, for instance in stir fries. In my garden some plants germinate in autumn and are available in small quantities through the winter. Others germinate in early spring and by March I have a good stand of it. It will grow in the open or in partial shade and likes a well-watered soil. It is rich in vitamin C: the name comes from its use against scurvy by gold miners in California’s gold rush. There are two closely related species: C. parviflora and the deep red C. rubra. I can’t find any information on the edibility of these but I’m sure they would be worth investigating: C. rubra in particular would look very striking in a salad.


Claytonia sibirica, pink purslane, is a perennial equivalent of miners’ lettuce. It is widely naturalised in Scotland, to the extent that there are locally named varieties, such as the white-flowered Stewarton flower found in north Ayrshire. It tends to form an extensive carpet in both broadleaf and coniferous woods: this looks spectacular when it flowers. In the forest garden it can be used in the shady areas under crop trees. The flavour is stronger than that of miners’ lettuce – something like raw beetroot.

Other species listed in the literature as having edible leaves include acutifolia, caroliniana, exigua, lanceolata, megarhiza, scammaniana, tuberosa, umbellata and virginica.
Finally, a number of species have edible roots, which go by the name of fairy spuds. Species include acutifolia, caroliniana, lanceolata, megarhiza, tuberosa, umbellata and virginica I haven’t managed to grow or try any of these yet but forager Euell Gibbons described C. virginica roots as tasting like sweet chestnuts when cooked.

Turnip-rooted chervil

I was being a bit of a pig in the allotment recently. Wild boar are one species that definitely didn’t get the memo about no-dig gardening. They have worked out one essential fact about the winter forest: the ground is where all the good stuff is. Their rootling behaviour – essentially ploughing up the ground looking for hidden bounty – looks destructive, and in some ways it is. Where densities are high they can cause an 80-95% reduction in herbaceous cover and the local extinction of some species. In other ways, their activity aids the health of the forest. Like any sensible pig, they prefer to target abundant species where they can be sure that all that work will be rewarded (you try digging up the earth with your nose, after all). As such they preferentially target plants with imperialistic tendencies, such as bracken and willowherb rhizomes or carpeting bulbs such as bluebells. This knocks back these aggressive spreaders, making space for a greater variety of species, and a number of studies have shown that over the long term species diversity is higher in areas with wild boar than in those without.
1024px-wildschwein_12.4.2008_117
Similarly, in the forest garden, there are some crops where a good rootle is the only way to harvest them at some times of year, and the resulting soil disturbance helps to make room for a range of self-seeding species that tend to get crowded out in entirely undisturbed, perennial communities.
One of these is turnip-rooted chervil, or plain root chervil (Chaerophyllum bulbosum), a biennial root vegetable in the carrot family. If you’ve never heard of it, that’s probably because it has a few oddities in its life cycle which mean that it has never been cultivated widely. The first of these is that the seed needs stratification (winter cold) in order to germinate, and loses its viability very quickly in dry conditions (like seed packets). This means that fresh seed needs to be collected every year and sown very soon after, in the autumn. This makes growing it in rows in a crop rotation quite awkward. One option is to simply allow it to self-seed around the garden, which it does very readily and which eliminates all the worries about sowing and stratifying.
The second problem is that it sprouts early and dies back early, generally at the first hint of dryness. When it dies back it does so without leaving a trace of where it is. This isn’t a problem in labelled rows, but definitely is when the roots have planted themselves randomly around the place. It isn’t helped by the fact that many people reckon the the flavour of new roots is poor compared to ones that have sat in the ground for a few months in cold conditions.
20151101_105701
All this leads to two main strategies for growing root chervil. The first is to sow it in annual beds in autumn, well marked and labelled. It starts to germinate here in early March, well before most crops. It then dies down by June, giving room for another crop, perhaps something like oriental greens which benefit from a late sowing so as not to run straight to seed. Finally it can be harvested over the winter. Some gardeners report problems with rodents getting at the stored roots, in which case a month in the fridge is also enough to improve the flavour. I find that chervil roots have a starchy, chestnut-like flavour that I enjoy a lot.
The other option is to let the plants take care of the sowing themselves, but this means that you are likely to have very little idea of where exactly they are by the time you want them. Until, that is, the roots have to give themselves away in order to grow for the new season. This is when you can harvest a great delicacy. A quick rootle will give you a pile of roots with young growth attached. There is no need to separate these as both parts are edible, just wash them well. By this time the flavour of the root has changed completely. The starch has been broken down into sugars, mobilised for growth, and the taste is now somewhat carroty and very sweet. It is impossible to get them out without a degree of soil disturbance, but, as the wild boar demonstrate, that is not entirely a bad thing in the forest garden.
20190221_151514
Whenever you dig them up, it is worth keeping the best roots to transplant to another bed for seed production. The roots show a lot of variability, in size, length and form. The default seems to be a round shape, presumably explaining the ‘turnip-rooted’ part of the name, but a proportion have an elongated, carrot-like shape which seems to be associated with higher yields. Given that you are likely to have to maintain your own seed line if you want to grow this vegetable at all, you might as well take the opportunity to improve the stock and adapt it to your own conditions as you go.

_MG_6099

Sprouting roots with the best separated out for replanting


I am always astonished at what a vigorous shoot comes out of a little chervil root. From a root usually no more than a few centimetres long they throw up seed stems over three metres tall. These can be very dense and with little leaf, so most of the nutrients required must be coming out from the root. This matches with the starchy flavour and a dry weight that is about 40% of it’s fresh weight. Chervil roots are clearly very dense nutrient stores. As such they could be seen as contributing to nutrient storage in the system as a whole. I am never too worried about surplus chervil roots that pop up and run to seed in unexpected areas of the garden: they are easily pulled out and put on the compost heap and don’t seem to bother the plants around them excessively as they are running on stores.
20180828_152618

Root chervil seed heads against a bright Aberdeen sky


There is more on TRC at:
https://www.cultivariable.com/instructions/root-crops/how-to-grow-root-chervil/
https://hort.purdue.edu/newcrop/proceedings1990/V1-422.html
 

Winter woes and wonders

It’s been a while since we’ve had a really testing winter in Aberdeen, so in an odd way I am rather enjoying the difficult one we’re having this year – as an opportunity to find out whether more recently acquired plants really are suited to growing in a forest garden in the north. We haven’t had any really deep freezes, but the continual back-and-forth over freezing point that we’ve experienced can be tougher for many plants than straightforward cold.

To start with those that definitely aren’t going to make it, I think I can firmly rule out milk thistle (Silybum marianum) for my garden. It was looking good after December’s frost and snow, but the extended cold seems to have been too much and all four of my plants are now withered husks. I’m also sad to report my mauka (Mirabilis expansa) as missing in action. This Andean root crop is widely described as growing in ‘cold, windy’ conditions at high altitude so it sounded perfect. My plants put on impressive aerial growth in 2016 but produced only small roots. I planted them in various positions around the garden to test out different conditions, but not one of them showed leaf again in 2017.

20180206_155825

Pan breid

Some other plants have been putting on growth but are now looking like they are regretting it. Prime among these is alexanders (Smyrnium olusatrum), a surprisingly hardy plant given its southerly distribution in the wild in Britain. It always starts into growth very early in its second year and never seems to suffer for it. What has been fascinating this year has been the differing trajectories of two different two-year-old plants that flowered and seeded copiously in 2017. One followed this by dropping dead in standard biennial fashion. The other not only clung on to life but sent up a mass of new flowering growth in November and December. This is now being progressively cut back by repeated frosts, but if I had to take a guess I would put my money on it making it through to spring. I’ll be keeping a close eye on this plant to see how far its ambitions for perenniality go.

20180206_154538

alexanders

Another surprisingly hardy plant is globe artichoke (Cynara cardunculus Scolymus Group). When I started growing, received wisdom was that cardoon (Cynara cardunculus Cardoon Group), a variety of artichoke selected for stems rather than flowers, was hardier. That’s all very well, but I’ve never found cardoon worth growing and I’ve never met anyone who actually uses it. Fortunately it seems that globe artichoke is just as hardy after all and mine regularly puts on significant growth in the winter, seemingly unworried by getting cut down by frost every now and again.

Of my newer experiments, I’m glad to see that the Chinese mahogany (Toona sinensis) is looking unaffected by the cold. Not that I’m expecting a mahogany crop any time soon, but the tree’s young leaves have a spicy, oniony flavour that I’m looking forward to experimenting with more. My Ohio spiderwort (Tradescantia ohiensis) has not only been surviving but growing throughout the winter. I’m very keen to try it once spring comes and I’m not worried about weakening it. Creeping dogwood (Cornus canadensis) is not an entirely new experiment. I’ve lost several that I acquired as plants in past winters. This time I grew one from seed. It survived last year’s mild winter and seems to be looking good for this year’s harsher one, so perhaps I’ll get to try its fruit eventually.

20180206_155336

creeping dogwood

The jury is still out on saltbush (Atriplex halimus). I had given up on this species after losing several plants over winter but decided to try again after finding a variety called ‘Cascais’ with larger leaves and shorter internodes – perfect for food production. Winter wet seems to be saltbush’s biggest enemy, so I gave this one a raised position on freely-draining sandy soil and crossed my fingers. So far it has suffered leaf scorch on a number of shoots but there is still a good bit of life in it, so I guess it will depend on what February and March throw at us. One advantage with saltbush is that it roots very easily from cuttings, so I have a backup copy on the kitchen windowsill.

Then we come to the real winter survivors. Land cress is the far easier relative of water cress. It grows throughout the winter and goes perfectly in land cress and potato soup, with the land cress leaves blended into a potato base at the last minute. Leaf celery (Apium graveolens) can be used similarly, and in many other ways besides. I’ll write a separate post about this under-rated vegetable soon. Kale (Brassica oleracea) is another great winter survivor, but I do find that the older perennial kales get the more susceptible they seem to winter cold. This is not only true of Daubenton’s kale but of Pentland Brig, an heirloom variety that has always shown a little bit of a tendency to survive an extra year or two. I’m told that in Florida this variety is genuinely perennial, but some of my three-year-olds are looking a bit touch-and-go this winter.

Salsify (Tragopogon porrofilius) and scorzonera (Scorzonera hispanica), two related root crops that can also be used for leaves and flower shoots, are both lasting well. Salsify is a biennial but it often germinates in autumn and then stands the winter. Perhaps the most unexpected winter survivor is wasabi (Wasabia japonica). Wasabi is possibly a little confused in this climate as it dies down and reappears at odd times, but it never seems too troubled by the cold.

20180206_154833

Variegated Daubenton’s – not a happy plant

I’m not entirely sure whether winters are getting milder or some plants are simply adapting to my garden. When I first grew leaf beet (Beta vulgaris) it generally died back over winter and only re-emerged come spring. This year many plants have been putting on significant winter growth. I must be on something like my eighth generation of self-seeded plants by now so it wouldn’t surprise me if there had been some selection for the conditions in my garden. I was also absolutely astonished to see a living rocket (Eruca sativa) plant. Rocket usually dies back at the first sign of frost. I’d be utterly delighted if it was getting hardier.

While some plants try to tough out the winter, others sensibly die back and wait it out undergound. While some of these won’t be seen again until May or June, others are more adventurous and quite a number are appearing already. Leading the charge is the onion family, including the chives (Allium schoenoprasum), Siberian chives (A. nutans), prairie onion (A. cernuum), German garlic (A. senescens), welsh onion (A. fistulosum), Sikkim onion (A. sikkimense), wild garlic (A. ursinum) and tree onion (A. x proliferum). They looked like they were regretting their rashness a little last week as blizzards swirled around them, but this is pretty normal behaviour for onions and I don’t think any of them will come to any harm from it. Only the three-cornered leek (A. triquetrum), which grew all through last year’s very mild winter, is looking decidedly unwell – perhaps not surprising for a plant more at home in the Canary Islands.

Then there’s the allium that laughs at winters, the queen of the Scottish vegetable garden, the leek (A. ampeloprasum). I have a range of perennial leeks, including elephant garlic, Babington leek and wild leek ‘Chesil Beach’ (which puts the song ‘Echo Beach’ by Martha and the Muffins into my head each and every time I see it), but perenniality is never far from the surface with leeks and many lines of cultivated, biennial leek occasionally form overwintering bulbs. This seems to me to be a promising route to new perennial varieties. For biennial leeks, I’ve tried many new varieties but nothing seems to beat the traditional ‘Musselburgh’ for winter hardiness and growth.

20180206_155704

Wild leek ‘Chesil Beach’. Far away in time.

Other plants already showing a bit of growth include the sour-leaved garden sorrel (Rumex acetosa) and a very handsome bronze lesser celandine (Ficaria verna). There are even some mushrooms! Jelly ear (Auricularia auricula-judae) and oyster mushroom (Pleurotus ostreatus) both seem to be unconcerned by winter cold.

With some other plants there’s nothing I can do but wait a little longer to see if they re-emerge from underground hiding this year. One of those that I’ll be most interested in is myoga or Japanese ginger (Zingiber mioga). This survived last winter but failed to produce any of the flowers which are its only edible part. If it makes it this time I’ve promised it a move to a sunnier position.

Finally, I’ll share with you the ingredients of last night’s curry, sourced almost entirely from the forest garden, to show that there’s never a time when you can’t get some sort of meal from it. Harvested that day: leek, potatoes, yacon, celery, salsify, hopniss (Apios americana), sweet cicely roots and leaves, jelly ears, leaf beet, kale, wasabi and alexanders. From stores: oca, beans, neep and apple.

20180206_155305

lesser celandine

Eating daylilies (Hemerocallis)

I’ve written a few times already about using daylilies but I thought it would be helpful to have one post to tie it all together.

Daylilies have been described as ‘the perfect perennial’, due to their brilliant colours and all round ease of growing. They tolerate both drought and frost and thrive in many different climate zones and soil conditions. They are vigorous perennials that last for many years in a garden and see off most weeds. As if all that wasn’t enough, they are really nice to eat too.

Daylily is not one species but a whole bag of them, all in the genus Hemerocallis. Plants for a Future list over 20 species and only one, H. forrestii, gets anything less than a four-star rating for edibility. Many daylilies that you might encounter do not fit strictly into any one species as they have been hybridised widely and many are listed only as Hemerocallis and their cultivar name.

I should add a few words of caution before I go any further. Daylilies are listed by some sources as poisonous to either humans or pets. Largely this seems to come from confusion with other plants with ‘lily’ in their common name, some of which are not a good idea to eat at all. Many of these plants also look superficially similar to the daylily so obviously you need to be certain that what you are eating is what you think it is (always a good idea in any case). There is a good article by Delishably on the some of the confusion that has arisen here.

All I can say personally is that I have experienced no ill effects from eating moderate amounts of the cooked flowers of Hemerocallis altissima, citrina, dumortieri, exaltata, fulva, lilioasphodelus, middendorfii and minor and a range of hybrids. Bear in mind that any individual can have an adverse reaction to even common food plants and any new food should be taken with some care. Each new species and hybrid is best treated as new rather than assuming that if you are fine with one Hemerocallis you are fine with them all. The only hazard for the genus listed on Plants for a Future is from a single source and states that large quantities of the leaves are said to be hallucinogenic, so you might want to avoid that (or you might want to try it – I don’t want to make any assumptions about my readers).

Daylily flowers are often recommended for salads, which is a bit of a mystery to me as I find them rather unpleasant raw but delicious cooked. The cooked flavour is rich, sweet and complex. The key to bringing out the best in them seems to be frying, which imparts a little bit of a caramelised taste. Perhaps the simplest method is to pan-fry them for about 5 minutes in olive oil. They might have been purposefully designed for stir-frying as their elongated shape is perfect for it. I cut up the largest H. fulva flowers for stir fries but all other kinds just go in whole. One useful property of the flowers is that they will thicken a soup or sauce and I sometimes use them like onion, chopped and lightly fried before adding any other ingredients. There’s a recipe for a miso soup using yellow day lilies (H. lilioasphodelus) here.

The flowers can be used at all stages of their development. Many people consider them to be at their best for frying as flower buds, just on the point of opening. I also enjoy the opened flowers this way and the open flowers of large-flowered species and cultivars are great for cooking as fritters or tempura. If left on the plant in dry weather the flowers will dry up and will then last indefinitely in storage. The bags of ‘golden needles’ or ‘lily flowers’ than you can find in Chinese supermarkets are dried daylilies. They seem to keep their ability to thicken a soup even when dried.

The young leaves of daylilies are edible (but see the cautions above) and I use them in a mixture with others as a pot herb or in leaf sauce. However, they are no better than many more productive plants and harvesting the leaves presumably leads to fewer flowers so I don’t make heavy use of them. They also quite quickly become tougher and more fibrous.

Another part that I don’t use for fear of weakening the plant is the roots, despite one source describing them as ‘quite possibly the best tubers I’ve ever eaten’. I’m sure, however, that if I lived in one of the parts of the world where daylilies really thrive and have become a foragable weed I would be digging them up with enthusiasm.

Growing daylilies is easy. They do best in a moist, fertile soil in sun or semi shade. There is apparently a daylily gall midge (Contarinia quinquenotata) which can lead to distorted flowers. Fortunately I have never seen it in my garden. Slugs are fond of the young growth. This isn’t a problem with established plants but new plants are worth protecting when first planted out.

Choosing a daylily is harder as they have almost become a victim of their own success. Many new varieties are becoming hard to recognise even as daylilies. The trend in breeding seems to be for ever more open flowers, with petals curved back hard – pretty much the opposite of what you want for cooking. Smaller flowers and delicate, divided petals are two more qualities prized by breeders but not by chefs. On the whole, this means that older, more traditional varieties are better for cooking. Varieties I use include Whichford, Burning Daylight, Franz Hals, Yellow Moonlight, Pink Damask and Cream Drop. You can also find double varieties of daylily which have the culinary advantage of being chunkier: H. fulva ‘Kwanso’ is one that I grow. Two common varieties that I have found rather disappointing in terms of size and yield are ‘Stella de Oro’ and ‘Corky’.

In countries where daylilies self-seed I expect there is a tendency to revert to type. If you are lucky enough to live in one of these countries and you find a particularly nice wild specimen I’d encourage you to take it into cultivation and pass it around. It’s a pity that no-one seems to be actively breeding daylilies for their culinary rather than their ornamental properties. I would certainly buy them.