All the way from South America, rather like Paddington Bear, comes my new favourite vegetable, Yacon, Smallanthus sonchifolius, distantly related to Jerusalem artichokes and carrying with it a host of intriguing culinary possibilities.
What is it?
Yacon tubers form underground beneath a robust, leafy plant, slightly reminiscent when dug of large baking potatoes, but that is where the similarity ends. Yacon, meaning ‘water root’ in the Inca language, has flesh that is juicy, slightly sweet and yielding, with a flavour reminiscent of pears, or melons, with a hint of celery. In fact in its home country, this beguiling tuber is used in fruit salads as well as vegetable dishes.
A most exciting feature of Yacon is the super sweet syrup that can be extracted from it, containing an indigestible sugar, inulin. In effect the delicious toffee-tasting syrup is virtually calorie free, does not raise blood sugar, and so both tubers and sweet syrup are suitable for diabetics. The inulin in yacon syrup also has great benefits for the bacteria in the gut where it is said to aid digestion and boost the immune system. These health benefits have lead to yacon becoming a major crop, especially in the US where most of the syrup extraction takes place.
Yacon is a tender perennial plant, therefore with a little TLC, once you have your first plant, it should be with you forever; in fact its cultivation and care are very much like dahlias, so if you grow dahlias, yacon will be a cinch! It is rarely troubled by any pests or diseases, easy and willing to grow, but does however need a long growing season, the tubers bulking up in the late autumn, to be dug in mild years just before Christmas, in advance of any penetrating ground frost.
To start off, either buy rooted cuttings in the spring or get a division from someone already growing yacon. I usually treat my stored crowns like dahlias, starting them off in the greenhouse until shoots appear. At that point I divide into individual plants and pot up, before growing them on for planting out in May in a sheltered sunny spot, when all danger of frost has passed.
Yacon does appreciate a rich, fertile growing medium with plenty of well rotted manure and compost, deeply incorporated into the soil. Cultivating the soil to a good depth before planting greatly helps the process of lifting the crop in the autumn, otherwise the main tubers can break off and stubbornly remain in the ground.
Once planted out, a lush and leafy plant will quickly develop to a height of up to 2 metres, with small orange yellow flowers in the late summer. If things are going to plan, the burgeoning tubers will start to raise the soil circling the crown of the plant around September / October time
Harvesting and Storing Yacon
Leaving harvesting as late as possible will give the most cropping potential. When the moment arrives, usually when the top growth has been blackened off by the first air frost, cut back the remaining stems to about 10 cm and dig up the crown consisting of the bulky storage tubers (the crop), plus small propagation roots, or ‘buds’ growing just under the surface. The crowns for next year’s plants are stored much like dahlias for the winter in a cool but frost-free place where they won’t dry out.
The big tubers, carefully snapped from the crown, are crunchy, sweet and refreshing immediately — after washing and peeling can be eaten just like a carrot — but they do have the potential to become sweeter if left out in the sun for a few days. Only undamaged tubers can be stored for several months in paper or hessian sacks, much like potatoes, in a frost-free garage or shed. Any damaged tubers should be used immediately or made into syrup.
Yacon in the Kitchen
Crunchy yacon is a delicious and different addition to savoury salads — try substituting the apple in Waldrof salad with diced yacon, or combine grated carrots, yacon ‘sticks’ and sliced celery with a grain mustard vinaigrette — in fact it absorbs dressings and sauces of all kinds very readily, making it a tasty vehicle for other flavours. In the Peruvian tradition of ‘salpicon’ (fruit salad), versatile yacon can also make a delightful fruit dessert when chopped and added to your choice of pineapple, melon, papaya or mango, dressed with fresh orange juice. If used raw, the flesh of yacon will discolour, much like an apple, so after peeling and preparing, sprinkle immediately with a little dilute lemon juice, or dressing, to preserve its attractive white colour. Alternatively, for a hot dish, yacon can be roasted with other root vegetables tossed with olive oil, balsamic vinegar and herbs, or even just simply steamed.
Once you have grown enough yacon to have some spare you can think about extracting the sweet liquid using a food processor — about 12 kgs makes a litre of the precious syrup. Simply wash and peel the tubers in batches then whizz them up thoroughly; place in a large pan and simmer down gently at about 103 C until a delicious dark brown syrup is formed. This sweet liquid is wonderful on porridge, or has a great affinity with cocoa when making ‘guilt-free’ chocolate treats!
Getting more from your garden!
By ‘getting more’ I mean multiplying up your favourite plants the cheap and easy way — by taking cuttings. Although September is thought to be late for taking cuttings, it is in fact my chosen moment. The busy spring and summer seasons of the gardening year are behind us, but light levels and warmth are still adequate to persuade the many half-hardies currently doing colourful duty in mixed borders and pots, to root in double quick time. By ‘half-hardies’ I mean the more tender perennials such as the larger Verbenas, Venidio-arctotis, Diascias, Salvias, some Osteospermum, and many of the foliage plants that are downright tender, including Iresine, Helchrysum petiolatum and Plectranthus argentatus. Interestingly I also routinely take Penstemon cuttings at this time of year, although they are hardy in the ground, I often treat them as annuals. In my garden, they flower their socks off in their first year for many weeks longer than older stock can ever manage.
I think it was the late, great gardener Christopher Lloyd who said that the process of taking cuttings is a ‘race between rotting and rooting’. Fortunately, with a little care, plants are much more willing to do the latter than the former!
Soft cuttings are taken from the ends of non-flowering stems, about three inches is what you need, and these chosen shoots should be strong, healthy and typical of the parent plant. While gathering cuttings from the garden, pop them in a polythene bag to prevent them wilting before you finish the job. I always trim my cuttings on a clean board, with a new scalpel blade that I sterilise between each batch. Working quickly, carefully trim off the lower leaves flush with the stem, and if you have a large number to do, mist them lightly during the process to prevent loss of moisture.
Trimming cuttings of Verbena ‘Homestead Purple’
When all of a batch are trimmed and ready, I dip the cut ends in hormone rooting gel. Most cuttings will root perfectly well without this extra help, but I find rooting gel does accelerate the process.
Dipping the cut ends in hormone rooting gel
As I have so many cuttings to do for my work, and for my own garden — around a thousand at this time of year — I use a rather high-tech rooting medium to speed things along. I find that pre-formed cubes made of biodegradable material, complete with a hole in the top for the cutting, are invaluable; not only do I get almost 100% success rate with these, but the plants seem to root more strongly, and most do so within 21 days. However, these little rooting cubes are by no means essential, most gardeners have good results by inserting the cuttings in damp potting compost just inside the perimeter of a three or four inch pot.
Inserting the prepared cuttings into the rooting cubes
Until roots have formed the cuttings need as much light as possible without ever being allowed to wilt or scorch. The way to do this if using a pot for the cuttings is to enclose them with a plastic bag held secure with a rubber band. A little refinement is to form a loop of wire, with the ends inserted in the pot, to hold the plastic bag clear of the leaves. I find that plastic in actual contact with the cuttings can lead to the dreaded rotting rather than rooting. During very hot bright days you may need to shade the pots to prevent overheating.
I am lucky enough to have a misting unit for my cuttings that works automatically with the aid of a ‘magic leaf’, a little gadget that senses when the cuttings are dry and initiates a burst of mist to keep them plump and perky until they root. You will usually know when rooting has taken place because the tip of the cuttings will start to grow away. If strongly rooted before the end of October, I pot them up individually in small pots and keep them just frost free, and on the dry side, in the greenhouse for the winter. A conservatory window cill would also be a fine location if you have only a few to overwinter. Those cuttings that have not rooted fully by the end of October, I simply leave undisturbed through the winter until the warming, lengthening days of spring encourage them into vigorous growth.
Some I prepared earlier — rooted in 14 days!
Although these tender perennials make great additions to borders — just as I use them in my garden to provide infill between the cannas, dahlias and ‘hardy exotics’ that form the backbone of my schemes — they are equally at home in more bijou gardens. They are happy in pots and containers where space is tight, and are joyously rewarding over a long summer season.
Groups from my own garden showing how tender perennials can lift mixed borders to another level, keeping them fresh and vibrant from late spring until the first frosts take them down.
Foreground, Venidio-arctotis daisies, raised from cuttings, with behind Dahlia ‘Bishop of Llandaff’, and seed sown Ricinus above
Foreground, spilling over the path is Verbena ‘Homestead Purple’, mingling with the tall pink Diascia personata, both from overwintered cuttings.
Foreground, Iresine and variegated Plectranthus argentatus, both tender and grown from cuttings. Background, Canna ‘Shenandoah’, and Ricinus ‘Impala’
I remember vividly seeing on television the literally earth-shattering images of the Mount St. Helens volcano erupting in the United States in 1980. This gigantic explosion caused the collapse of a large portion of the mountain together with the ejection of millions of tons of volcanic dust which settled over eleven US states. In the immediate vicinity a wasteland was created with the land buried in a massively destructive deep layer of ash, however in further outlying agricultural areas, some remarkable effects were reported from a lighter deposit of the rock dust. Farmers noted a huge increase in yields — even to the extent that abandoned and unproductive orchards suddenly started producing viable crops again.
What had happened as a result of the eruption was nothing short of a natural ‘re-mineralisation’ of the land. For thousands of years peoples have settled on the slopes of volcanoes (sometime with disastrous results, as in Pompeii) due to the exceptionally fertile and productive soil, rich with minerals and trace elements. Glaciers are another natural method by which soil was created and made fertile. During the last ice age the crushing action of ice on volcanic rocks ground away the strata to produce many deep rich soils, that still feed human populations today, 10,000 years later.
For those of us who grow substantial amounts of our own food, keeping the soil replete with macro and micro-nutrients (or trace elements) is an important way of making sure that we also ‘mineralise’ ourselves for health and well-being. A tiny but very significant percentage of vegetable and fruit crops is made up of minerals, but most modern fertilisers replace just the basic NPK (Nitrogen, Phosphorus and Potassium), neglecting the vital trace elements, such as magnesium. The taking of crops from the land without efficient replacement of these nutrients, together with natural leaching from the action of weather, means that many soils are now nutrient deficient, which in turn implies that the whole food chain is similarly depleted.
Recently I discovered that rock dust can now be obtained that does the job of a ‘mini Mt. St. Helens eruption’ when spread on the soil — it puts back the mineral goodness that plants and ourselves need to thrive.
In the spring I top-dressed a bed for my maincrop Kestrel potatoes using about a handful per sq.m of rock dust, raked in prior to planting. I did see a very noticeable increase in plant health and vigour — the tops appeared ‘super green’ and lush, but the yield from one root, at well over 2 kgs, I thought was definitely impressive. Next spring will see me ‘dusting’ the kitchen garden once again!
Spreading Rock Dust at about one handful to the sq. m
Raking into the surface prior to planting
Potato Kestrel in growth
Yield from one root of Kestrel grown on the re-mineralised ground
Most of us tend to view the world of microbes with some suspicion, convinced that these bugs can do us harm or make us unwell, in fact there is a whole world of beneficial organisms out there that can help us unlock additional nourishment from our food, and at the same time populate us with ‘probiotics’. Thinking about the foods and drinks we value for their taste and beneficial qualities – wine, sourdough bread, yogurt, olives, blue cheeses, to name but few – all these are created or processed with the help of the ‘good bugs’, without which many gourmet foods would simply not exist.
Almost all the traditional cultures of the world have learned independently to ferment vegetables – the French have a fermented cabbage known as ‘choucroute’, the same spoken in German is ‘sauerkraut’; right through Asia including China, Vietnam, Japan, Korea and Malaysia they make ferments called kimchi, traditionally eaten with every meal. This lactobacillus fermentation process not only preserves the food in its raw state, makes it more digestible, but also endows it with extra nutrients and vitamins over and above that found in the original raw food. The explorer, Captain Cook, understood the benefits of fermented foods; in the 1770’s he took 60 barrels of sauerkraut on a voyage that lasted over two years, and returned with all his crew free of scurvy, the deficiency disease that previously decimated ship’s crews on circumnavigations.
Many of the vegetables that we might have in storage from last summer are still perfect for fermenting – red cabbage, carrots, onions, turnips, celeriac, winter radish and beetroot – will all produce tangy, nutritious additions to meals. Fermented veg are used as a condiment, in the way that a small amount of chutney might accompany cold meat or a salad, rather than eaten by the plate full. The taste of them is sharp, fresh and ‘grown up’; those with a very sweet tooth might find them an acquired taste, so if you always prefer the dessert trolley to the cheese board they may not be for you!
A great introduction to the world of fermentation is Sandor Katz’ book ‘Wild Fermentation’. This video is a talk given by him outlining basic principles:
I recently made up a jar of Cortido, the South American version of fermented cabbage, using up some of my stored vegetables in the process, and transforming them into something rather exciting! The recipe I used is from Sally Fallon’s very good book ‘Nourishing Traditions’, and her full recipe can be found online here.
Collected ingredients for Cortido
Assembled ingredients ready to be mixed
Pounding with the end of a rolling pin to release the juices
Seal the jar so that about 3 days of fermentation can begin, after placing in a warm spot
Although ferments can be started without using whey, I find the results are much more predictable if the mix is inoculated with whey. Whey? This is the slightly cloudy, yellowish liquid that can be strained out of liquid dairy products – easiest to make at home by buying a carton of plain ‘bio live’ organic yogurt and straining it using double-folded butter muslin, or a coffee filter, placed in a sieve over a container. The whey will slowly drip through, leaving you with ‘yogurt cheese’ in the filter. Whey keeps for months in a closed jar in the refrigerator.
After the fermentation period is complete, the vegetables can be eaten straight away, but taste much better after a month or two of storage – they become more mellow and flavourful with the passage of time. Just leave them somewhere cool, or if your house is too warm, then the top shelf of the fridge will be fine.
One of my favourite ferments is carrot and ginger — easy and tasty for those trying this clever technique for the first time.
Fermented Carrot & Ginger — ‘one I made earlier’
Guest blogger Phillippa Lambert writes about growing Oca – a versatile and tasty vegetable.
A new vegetable crop for me this year is Oca (Oxalis tuberosa), along with Yacon, (a treat for next growing season), Oca is one of the ‘lost crops’ of the Incas, and a staple crop in Bolivia and Peru. It is grown from tubers, much like potatoes, but is not related to them in any way, hence they are blissfully free from blight. Oca produces attractive yellow flowers set against prolific trefoil foliage, that acts as effective, and largely pest-free, ground cover. The only drawback is that Oca is tender (preferably started under cover in the spring), and needs a moderately long growing season to achieve a worthwhile crop.
Oca can be cooked like new potatoes (very tasty with a lemony tang), roasted in the oven, or even used raw in salads in much the same way that radish is prepared.
Oca roasted in olive oil and balsamic vinegar, with red onions and beetroot, dressed with soured cream
Oca and watercress salad
I started off my Oca in the spring from small chitted tubers, in the greenhouse in Root trainers. As soon as the weather warmed up enough (early May on the Isle of Wight), I set them out in rows, 12″ between plants, and about 30″ between rows. They require very little work during the growing season apart from keeping down any weeds before the foliage closes over, and some earthing up to increase crop yields. An absolutely crucial piece of information is that Oca does not start to form its tubers until the days shorten in the autumn — it is day length dependent. The key to a heavy crop is to keep the leaves protected from frost as long as possible — fleece may be necessary if early frost threatens — and only dig the crop about 2 weeks after the top growth has been completely killed by frost.
Oca, fleece-covered in late November, to preserve the top growth as long as possible
Storage is easy; as Oca does not react to the light by going green, as potatoes do, simply sort the crop — the larger tubers for eating, smaller sizes for next spring’s seed, and place in paper bags in a consistently cool place. Refrigeration is not necessary. Those for planting can be chitted in a frost-free, light position in early spring, (just like potatoes), and the whole cycle starts again!
Lifting the crop just before Christmas
Lifting the crop just before Christmas
Washing off the tubers before storing
Washing off the tubers before storing
A selection of both colours
A selection of both colours
Read more about Phillippa Lambert at www.lakehousedesign.co.uk