Other plants on Offer

Oca (Oxalis tuberosa). Store the pink tubers in a cool, airy place, and plant out in early May. It will form a low bushy plant. Frost will kill the tops in autumn: I mulch at this stage, to allow the succulent stems to continue feeding the tubers, which start developing late in the season. I've realised that leaving the mulch on for any length of time allows slugs and other pests to eat the tubers: I've yet to determine the optimum lifting date. I eat the tubers in salad, and later, the sprouts growing from them. They're said to be sweeter and less acidic if left on a sunny windowsill for a week. The green shoots are also tasty. However, all parts contain oxalic acid, which clamps onto iron and other minerals, making them unavailable to the gut: so eat in moderation.

Potato Bean (Apios americana): has brown tubers that gradually desiccate in open storage, making them slow to sprout – so store in pots of compost, unwatered, until about April; or leave buried in the ground. (Clean ones also seem to store well in plastic bags in the fridge, but check for the occasional mouldy one.) Then pot up, insert a small cane (avoiding the tuber) and provide water and warmth. Plant out after danger of frost and grow alongside your runner beans. They shoots are liable to slug damage while young. Water in dry spells - in the US, they're a pest in Blueberry fields, that's how much they appreciate moisture! And the tubers get lost in the blueberry roots. Which means it's a good idea to plant in a dug veg bed, well away from perennials, shrubs, paving and lawn. Harvest the strings of tubers (one stretch of root can have many tubers along it, like beads) in winter. Boiled, they taste like baked potatoes: they're more concentrated than spuds, with lots of protein. They were once considered as an alternative to potatoes during the Irish famine. If you hang on to the 'mummy' tuber - it gets bigger year after year, producing a stronger plant each time - but suffers rot in parts. Here's a picture of a real oldie weighing about 850g.
That was taken early 2009: the following winter it had rotted to virtually nowt. And big tubers have a habit of feeding themselves rather than spawning many new tubers - so use them up, and plant the new ones. Old tubers are edible (before they rot!). There's an interesting article in Orion Magazine, from the US, PFAF website.
and useful information on the

Achoccha (Cyclanthera pedata): black seeds looking like witch’s teeth. Sow in spring, as other members of the squash family, and plant out in rich soil after danger of frost. Water if necessary. It can monopolise a bean pyramid. Climbs by tendrils, so appreciates twigs rather than canes. Crop the fruits for salad when no longer than 2” (5cm) - preferably at 1½",  otherwise they get ‘chewy’. Don’t worry if you miss any – they’ll form seed for next year, and on a vigorous plant don’t appear to hinder the formation of further fruits. 

Sweet Cicely (Myrrhis odorata): long thin seeds that grow into a perennial, aniseed-smelling, herb. Sow the seeds when they happen in autumn - they need frost treatment. Use the leaves or scrubbed roots in cooking; the young seeds are good raw.

Alexanders (Smyrnium olusatrum): black seeds in ‘foetal’ shape, with peppery smell. Sow the seeds when they happen in autumn, or perhaps spring, where they are to grow. Use the leaves or young shoots in cooking – parsley-like flavour, or the peppery seeds (I've got some in a peppermill!). The flower buds and young umbels are tasty raw, and the young flower shoots, well before there's any sign of buds, make a tasty dessert briefly fried and coated in icing sugar. (In the picture, that's flowering quince in the background). A big asset is that the leaves survive the winter well, just wilting when frosted then picking up as they thaw, so they're available throughout the winter. It's also good looking and the flowers, in May and June, are fragrant! In flower, it's about 4' high. Naturalisable, but keep away from ground elder - they have similar leaves (but thankfully different habits).

Quince (flowering) - Chaenomeles japonica, C. speciosa. A common garden flowering bush. The smaller fruits of the former smell distinctly marmalady in autumn and are brilliant flavouring; but they have a short shelf life. The larger fruits of C. speciosa are make it easier to cut the flesh off the core, and they last longer. They're a great lemon substitute (though too firm for squeezing). I use them in apple sauce, curries, and in flapjack. Such flapjack is lifted by a small sprig of rosemary. Both reach 6' or so, C. japonica slowly suckering.
Poppy - Papaver somniferum. Beautiful flowers, forget the resin - when the seed capsules start to open their vents at the top, it's time to gather them. The seeds are not narcotic, although I've heard your urine can test positive after eating them! Let the seed heads dry out fully, put them into a jar and SHAKE! Pour the contents through a kitchen sieve - it should let the seeds through without the gubbins. Bread-making time! As for growing it - just scatter and let it do it's weedy thing. For more on edible seeds and flower heads (fennel, lavender, coriander, dill, lovage, and New Zealand flax) see Alys Fowler's column in the Guardian, 23/7/11.)

Wild Chamomile. There are a few chamomiles - here we're talking of Matricaria recutita, a fragrant annual weed with daisy-like flowers. For a delicious cup of herb tea, put perhaps 3 flowers (depending on taste) in a cup with boiling water. You can also dry them, on an open tray indoors, perhaps (but not necessarily) on top of the boiler, for storage in jars and later use. I've known of caterpillars amongst the stored flowers, so check. Pineapple Weed is related, and can be used similarly; flavour like pineapple. I don't keep seeds.
Jerusalem Artichoke - Helianthus tuberosus. I don't offer this - too expensive to post, and you can get them easily enough from veg shops and gardening mates.  (For some reason they're always pleased to pass some on!) Plant in winter or spring, leave to grow (young shoots may need protection from slugs) and harvest the tubers as required in winter. If you're planning planting something else there, be ready to grub up any artichokes you left in: I've not yet succeeded in getting them all out - crop rotation with these is futile! You can plant for next season simultaneously. Tubers deteriorate, losing water, in storage. Plenty of recipes for cooking; my favourite is just to scrub and eat raw! 
Butternut Squash - Cucurbita moschata. I get my seeds from bought fruit, or if I'm lucky, plants I've grown from same. It appears they may not hybridise with other cucurbits (unlike a vegetable spaghetti I kept from year to year, gradually getting more marrow-like.) Start in spring indoors, as any cucurbit, and plant out in fertile soil. May need watering in dry weather. Allow to trail, or they can be encouraged to grow up strong canes. Cut ripe fruits off through the stalk. Young late fruits are delicious raw.
Winter Radish - sow summer, reap in winter. One we dug up weighed 2lb (pic). While slugs were devastating our little salad radish, these were untouched. Probably because they're hot! One thin slice needs plenty of other salad on your plate! And if they go to seed, do as the Chinese would - harvest the flower stalks. Very young, they'll do for salad (pretty flowers), they're also great in stir fries, etc. A bit further gone, and you can eat the young pods. After that, you're harvesting the seeds. I've seen radish seedlings for sale in our local supermarket, and have tried growing these seeds on a windowsill - they don't believe in synchronisation! (Maybe there's a technique.) Take the ripe, dry pods and give a bit more drying indoors, then rub briskly between your hands to release the seeds (leather gloves may be helpful), dropping everything into a dry washing-up bowl. Take it outside, tilt and shake everything to the bottom, and blow the chaff off the seeds, which being heavy and round, will keep to the bottom. Remove the chaff as it gathers at the top, and repeat. Then shake the chaff out of your hair! We inherited this variety, it's probably Munchen Bier, or M√ľnchner Bier.
Burdock: a native biennial, Arctium minus. Left to go to seed, you may attract goldfinches: you'll certainly get their hooked seedheads attached to your clothes. Received advice has been to transplant seedlings in winter, and providing they're weedy little roots are as thick as a biro's inside, no fatter, you stand a chance of them using their subsequent year just growing, not flowering. In the open ground, digging out the mature root is difficult: the top is some way down, and the bottom is a lot further! More recently, I've seen burdock in a Chinese food market, about 3 foot long and straight. So I tried growing in the tyre stack (above). Got great growth, huge leaves, great roots (those on the right came it at 1.75kg, nearly 4lb) and so much easier to extract! The best way seems to be to sow seeds in the tyre stack, or a bin with drainage, in late winter, have about 4 plants growing together, and harvest in the following winter, keeping them watered throughout summer. Although naturally a plant of woodland edges, they'll respond to a watered tyre stack in the sun, producing enormous leaves and a good crop of roots. In a trial, I had one transplant and 4 seedlings in a stack; two of the seedlings each produced a straight, single tap root. Transplants have always produced branched roots for me. We peel it and soak in water for 10 minutes, then boil it. We enjoy potato and burdock cakes - bit like potato cakes, they made with a mix of boiled potato and burdock, with veg oil and flour. Burdock roots are also good roasted - you don't need to peel them for that.Seeds available, or quite common to gather. Young flowering stems can also be eaten, raw or cooked (I've not tried yet). Avoid breathing the seed hairs. Arctium minus is one of our native burdocks, the Japanese grow Arctium lappa for food, and this latter is the one normally sold as seed.
Tomatillo. This you grow like a pepper, and it's tough enough to survive outside in summer. Like a pepper, it branches each time it flowers. The flowers are attractive yellow things, held face down beneath the branches attracting bees. But pollination is very occasional, so I've been using a paint brush - you have to do this before late afternoon, otherwise the flowers close. The pollen is fine, and seems to be released explosively onto the brush by all too few flowers. When you succeed, you get a golfball sized fruit (ours is green) within a husk. The fruits have sticky waxy coatings that enable them to stay good for months indoors.
Mesembryanthemum. The Livingstone Daisy of flower borders, whose bright blossoms enlighten sunny days. The leaves are good in salad - crunchy and very mild, certainly in autumn. Mine are growing in a hanging basket, away from slug interference, and with a hippo (thing you use to reduce the amount of water flushed by a toilet cistern: it contains a water-absorbent gel) buried in the compost. No seeds available.
Epiphyllum. Let the berries develop on your Epiphyllum/Orchid Cactus: the taste, when they eventually ripen, is out of this world! (Cuttings available, random varieties)
Sweet Potato. I tried again! This time, under a cloche, we manage to get something thicker than a pencil. Variety is from New Zealand via our local shops, called Kumara (a Maori name for Sweet Potato!) I'm not bothering in 2009. 2013: I'm trying a bought plant in the greenhouse. I've also tried Murasaki, managing to keep it a couple of seasons before managing to kill it. One winter it seemed to survive in its pot, brought indoors; the next, after breaking some off for eating, it died. Did it need extra drying after the break?
Dahlia. Once grown for food (and maybe still is), us Brits have taken to planting them in
flower beds, admiring the show, then throwing good food away with the tubers. The dwarf varieties have tiny tubers, and seem more susceptible to slugs, you want the larger types. Like potatoes, different varieties will taste different, so see what you like. Petals are good in salads. No seeds. My variety is 'Wars of the Roses'; it's got a wobbly gene makiing the petals either red or white, randomly.
Hazel. I love this - it's definately got permaculture's requirement of at least 3 purposes. In February, out come the catkins: the plant is covered in yellow lamb's tails, telling you spring is on it's way. Take a branch indoors and put in a vase of water: a week later, with no wind blowing it, the catkins will be loaded with pollen, so a flick will produce a cloud of it. In autumn, there's the nut crop. They need cross-pollination: for an article on this, see pdf on Oregon State University's website. Finally, there's a need to trim it, removing long, straight, useful canes. You can plant vigorous climbers to grow up it - I've got Japanese Yams growing through mine, I can't see where they're up to; you may prefer decoratives, but think carefully before planting woody climbers as you may have difficulty pruning. That's 4: if you're up to the trouble of extracting them and enjoy the taste, you might try planting one inoculated with truffle spores.
Juneberry - small suckering tree, very pretty with its white spring flowers. Mine's probably Amelanchier lamarckii, not renowned for its fruit, which are the size of small currants, ripe when they turn a dark, bluey red and pull off easily in your hand. They're well spaced apart, and ripen sequentially, so although tasty, they're inconvenient to pick. And blackbirds love them. So enjoy the flowers, and let the fruit distract the birds from your strawberries! There are larger fruited cultivars, like Martin, Northline, Regent, Smoky and Thiessen (per Martin Crawford, https://www.agroforestry.co.uk)
Ribes odoratum, Buffalo Currant. This shrub has long, weak shoots; by good fortune mine's planted beneath a Rowan, whose lower branches support it. It's blessed with gorgeous yellow flowers in spring, with a delicious perfume. These are followed by small black currants, tasting rather like blackcurrants. You'll know they're ripe from the attentions of blackbirds. You can pick whole bunches as long as some are ripe, but you may prefer to pick your other fruits and leave these for the birds.
Potato. It's not hard to grow these from seeds, though the results are unpredicatable - but you retain fewer pests and diseases that if you save your own tubers. Collect ripe berries fallen from favoured plants, and split out the seeds - you can spread these on paper, or use the technique used for tomatoes if you prefer. I sowed mine, collected from Sarpo Mira berries, in early spring indoors, transplanted and planted out. Gathering in the first crop, I found a mixture of sizes, shapes and colours, despite them all coming from the same mother. I replanted, and grew for their second season, getting a reasonable crop. So a mixture of characteristics, including blight resistance - one seedling was particularly promising. I've noticed that I only get berries on my Sarpo Mira on the allotment, where it can be pollinated by other spuds: there are no berries on the plants in my garden, where there are no other varieties.
Sowthistle. This scrappy annual weed is actually tasty! You want the Smooth Sowthistle, not the Prickly Sowthistle: taste is the same, but latter is a tad rougher on the palate! Take the young shoots and add to salad; they've got a slightly bitter taste like chicory or lettuce stem. I don't bother saving seed, I just let the odd seed head do its thing. So simple to grow, just pull out the seedlings that are in the way; and it's not bothered by slugs! This one has been growing overwinter in my greenhouse, absolutely loving it, and this branch is about to be cropped before those flowers go over. But the plant will have to make way... I need the space.
Evening Primrose. I have Oenothera biennis: bright, yellow, lemon-scented flowers that open in the evening and fade the following day. I always let it seed, and often see goldfinches sitting on the dead flower heads in winter, picking at the seeds for minutes on end. Of course, this means they come up like weeds on disturbed ground, and need extracting to allow other crops space. We cook them, in stir fries and with other green veg - just trim off the dead and dying leaves, and the fine roots to leave yourself with the main red+white tap root, and wash.

Hyacinth Bean. Too early to say its worth - starting with just 4 seeds and not a vast crop coming, there's no room for tasters until frosts loom. It seems to appreciate warm conditions. Very pretty, slightly scented flowers against dark foliage in this strain, and wacky pods - look! Crop from 2009: 5 seeds! I tried starting them earlier... except none came up. And their allegedly perennial roots got frosted. 2011: have bought a packet of beans from a Chinese food wholesaler, so lots to play with! Unfortunately these are possibly a short day variety; I never saw any flower buds.
Land Cress. Another plant that will happily seed itself, so you can forget about packets of seed and sowing rows. It's a relative of water cress, but tastes stronger (especially the flower heads) and doesn't need running water - ordinary soil is fine. It seems to come up any time of year, but those that start in the latter half don't seem to run to seed so readily. It will then provide winter salad greens in all but the worst weather - providing (as on our plot) pheasants aren't pecking it! For best results, protect the winter crop from the worst of the cold weather, and keep the summer crop watered. Grow about 9" apart.
Bistort. This perennial forms an expanding patch, with dock-like (but clearly not dock) leaves in spring, later topped with waving wands of pink flower spikes. No great taste in the leaves, but they're OK cooked and were once a vitamin C staple before vitamin C was heard of. I think mine's a cultivated variety of Polygonum bistorta, with slightly thicker flower spikes. Popular with bees, and does produce seeds, which come up in favourable spots.
Meadowsweet. I grow this by my pond, to take advantage of the overflow and allow me, during dry spells, to splash some water via it into the pond. It forms a slowly expanding patch. In summer it forms its gloriously scented fluffy white flowers; a small portion of which (I use a lump about an inch across) make an aromatic cuppa using just boiling water. If it gets dry, it suffers mildew, which can spoil the flowers.
Mashua (tuberous nasturtium). This is mainly grown for its edible tubers, which are said to require an acquired taste: as this is my first season with them, it's too early to report. After beating off many attempts at colonisation by blackfly and cabbage whites, my two plants, grown in pots so that I could extend their season into frosty times, produced these elegant little flowers. The taste of the flowers knocks spots off garden nasturtium: that spur at the back is chock full of nectar! That's followed by a gentle peppery kick! I've lost this, so many slug problems last year it never got going, and perhaps the competition from the oca in the same container was too much. 
Ramsons, the wild British woodland plant, is brilliant to have growing handy in the garden. One leaf adds a garlicky bite to a cheese butty, and I know someone who makes an ace pesto with a bagful of leaves. I also like to use the flower and seed heads while I can see them - saves them seeding around. The bulbs are especially pungent! Leaves and flowers only available in spring and early summer.
Cherry Plum or Mirabelle. Forms a suckerless (I've not seen any) tree, covered in white blossom in early spring, and followed in August (July this year, 2011) by cherry-size, plum flavoured fruits with a flattened stone. The fruits come in various colours from yellow through to deep red - my tree has yellow fruit.
Balm of Gilead, Cedronella canariensis
Beautifully aromatic foliage. A not reliaby hardy small perennial bush member of the mint/sage/thyme family, best therefore grown in a pot. Fantastic for herbal tea.

Aromatic, almost minty leaves; great for summer flowerbeds too, the spikes of blue flowers attracting bees. Start off indoors in pots, just covering the seeds, which may take 1-3 months to germinate. Also easy from cuttings. Possibly hardy, but easy to save seed and restart. Great for herbal tea.

Pepino, Solanum muricatum
Another plant grown from seeds from bought fruit. This tomato relative is said to be blight susceptible, so I've grown it in the greenhouse. 2013 was my first year with it; I got one fruit maturing on my one seed-grown plant, and had hoped that it'd mature before the frost! Again, this is a perennial, so I'll be protecting the rootstock; it also roots easily, so I'm taking cuttings. I'm hoping this will produce flowers earlier next year, and give a reasonable crop. It forms an upright bush, and hasn't needed any support. The flowers apparently need night temperatures above 18C to set. Any whiff of frost or low temperature is not appreciated, and warmth appears to be needed by cuttings.
Vietnamese Coriander, Persicaria odorata
An unexciting plant resembling the weed persicaria, but more upright, with a coriander scent and a slightly peppery taste. It never flowers (or I've not seen any), but cuttings root very easily in water. Add leaves at the end of cooking.
Buckshorn Plantain
A British native evergreen herb (though my seed's originally from elsewhere) of the coast. So far, I've only grown mine in pots in the greenhouse; they'll mature and flower in 3" pots, but form lusher plants in bigger pots. The leaves have a delicate taste, the young ones without the fibre known of inland (ribwort and ratstail) plantains.
A herbaceous pond plant producing tasty tubers. I've grown the native Sagittaria sagitifolia - it produced small tubers. The non-native Sagittaria latifolia, which I now grow, has tubers the size of door knobs, that you can spot floating in the water when the mating frogs start disturbing them, so you can harvest them. They'll also grow in a bucket of water (I don't allow these to freeze). The leaf stalks are feeble, so need shelter, but the plant needs light too. I cook the tubers - they have a starchy texture like potatoes, but a flavour of asparagus.   

For more information on these plants (and many others), see the Plants for a Future website, http://www.pfaf.org/

A video about Kitchen Gardens featuring some unusual plants, with Alys Fowler

First half is about perennial borders, including shots of our local Arley Gardens. In the second half Alys visits various gardens including the new Edwardian Kitchen Garden at Tatton Park (also local), and introduces all sorts of things we might try. Of which, the only unusual I've established has been Babington Leek!

Babington Leeks

Important notice to seed swappers -
the growing season for Babington Leeks is September to June, and new bulbils mature in September/October. So I prefer/you'll prefer/they'd prefer if I send them in autumn and you plant them on receipt.
I look forward to dealing with your request in Septemberish: email antthehat on my hotmail.com account.
Japanese Knotweed
The best source of information I know of is Leicester University - http://www2.le.ac.uk/departments/biology/people/bailey/res
Gives useful information on the all-female clone of the species, the less common Giant Knotweed that is hermaphrodite but can't set seed without cross-pollination, and how to tell these two and their hybrid apart.
The photos are largely unlabelled - right click on them and select 'View Image Info' to see the associated text, which will tell you about it.

Giant Hogweed
I've come across a thorough paper on Giant Hogweed, from Countryside Management Publications, including identification, dangers and removal - by both chemical and physical means. It came up in a search and I don't know the URL, so I've filed it here. I trust it will serve your purposes, but as I didn't write it can't vouch for any mishaps using it.

List of Seeds and Plants available & wanted

I've the following available, in various quantities. Lots of unfamiliar species - so see further down the page for information. Seeds unless otherwise specified.
Achoccha (Cyclanthera pedata) (No fresh seeds) 
Alexanders (Smyrnium olusatrum)
Apples (I grow Annie Elizabeth, Kidd's Orange Pippin and Ingrid Marie. Let me know which you want me to keep seeds of - although I've no control over the pollen parent. There are other apple trees in nearby gardens, including, unfortunately, a crab. I believe, having come across many tasty feral apple trees, that good apples are not so dependent on intensive breeding as breeders may like you to believe - you just have to ensure there's no crab apple pollen involved.) This year I've been collecting seeds from local Northwich varieties - found by the wayside, also of what I suspect to be Wisley Crab, which is more of an apple than crab, with red flesh.)
Babington Leek (bulbils)
new crop September. (details here) 
Balm of Gilead (Cedronella canariensis, sometimes C. triphylla) (amazing scent, but not many seeds)
Bistort (small quantity of seeds, none this year) 

Burdock (Arctium minus)
Chaenomeles speciosa and japonica (no japonica this year)
Corn Salad AKA Lambs' Lettuce (small quantity, fiddly to collect)

Evening Primrose (Oenothera biennis)
Garlic Chives (run out, may have some coming on)
Land Cress (American, I think)
New Zealand Spinach
Perpetual Spinach
Potato (from Sarpo Mira berries: Sarpo Mira is blight resistant. It seems seeds these are crossed with all the other varieties on the allotments, so very variable, many inheriting blight resistance.)
Runner Bean (mixed varieties)
Sweet Cicely

Tomato Salt Spring Sunrise
Winter Radish (white root, more than a hint of horseradish pungency! Probably Munchen Bier) 
Also Red Kabocha Winter Squash, courtesy of a bought fruit. No guarantees it will breed true; there may be some Green Kabocha pollen involved, or others.

Bistort roots

Oca tubers
Potato Bean tubers

Ramsons bulbs/plants, depending on season
Vietnamese Coriander cuttings

I've posted details of some of these below

Please email me, antthehat, on my hotmail.com address for postage rates: for seeds (other than big seeds, including perpetual spinach) only, this will usually amount to normal posting rates. Otherwise, large letter postage is required for Babington Leek bulbils, legumes and most roots. Some extra consideration would be great, but not essential.

If you've anything interesting to offer, please say

Found a Slime Mould - Fuligo septica?

This was growing on a long-dead conifer log in our Cheshire garden, appearing a couple of days into a hot spell following a damp and cool English July.

Thursday it was yellow and granular in appearance, but evidently very moist.

Friday it had turned black, with evidence of slugs/snails having foraged overnight.

Housing Crisis? What Housing Crisis?

From the quosac2 blog Why do we need more houses in the UK? Why are house prices sky-high, and unaffordable by essential workers? Why do kids, old enough to move out, stay at home and spend their quite reasonable earnings on booze and cars? Why are more elderly people living on their own, necessitating carers to drive round in cars? Why are cars so necessary?
I'm sure if you add up all the bedrooms in the country, you'd find a surplus.
Surely, if people opted for sharing their homes, or move into shared homes, we could instantly get more accommodation. Young people can share, old people can share, mixed ages can share. Single households generate more waste per head. Single households need more heating energy per head. It's hard work maintaining a house on your own, especially if you need to work, or if you're elderly.
Government specs for new developments aim to cram them in - great for squeezing them onto brownfield sites, but pathetic for gardens, which are breathing spaces, places for drying clothes, composting waste, growing food, appreciating nature.
Shared housing shares burdens and costs, provides company, provides security, provides care when you're down. People in shared housing find they can afford to work part-time; they can downsize on their personal material comforts, upsize on their social and shared comforts.
Divorce is another issue - I blame lack of conversation in this busy-busy-busy lifestyle. The more you have, the more you have to look after - so cut it out. Axe telly-time, talk. And don't dream of winning the lottery - it won't happen, and any charity will benefit more by direct donation. If you've got a dream, work towards it - dreaming won't help!
In a large group, you can have babysitters, granny-sitters, dog-minders, specialists, and hearty entertainment - jam-sessions if you're musically minded! And how many cars do you need? Not many.

Freestyle Foods

On land where your tenure is unsecure, you want food that requires a minimum of money/effort. So:
scatter a manky pot of raspberries or strawberries (you can make a herbal tea from the leaves of the former)
toss your applecores (some of the best apples I've tasted have been from such seeds, chucked by the wayside)
...and some hazelnuts
planted ornamental almonds can offer tasty nuts (if too almondy, then too much hydrocyanic acid) - but you may need adjustable spanners to crack them
learn to recognise Ground Elder and know it from poisonous relatives - it's great cooked as spinach, or young leaves in salad. Don't introduce it to your allotment though!
plant roots like carrot and parsnip from the grocer - they'll give cheap seed

plant Jerusalem Artichokes for an excellent crop of tubers, that are wonderfully crunchy scrubbed for salad - but only harvest them when you're ready for them, as they don't store well.
other tasty wild plants: ramsons (wild garlic), common sowthistle (lettuce-like)

Babington Leeks

Babington Leeks (Allium ampeloprasum var babingtonii)
Babington Leeks are a perennial, rare UK native, found on south-western coasts, with the following life-cycle:
Ripe bulbils fall from September on, to root and develop on the moist winter soil. They are unlikely to reach full size in their first season, especially if you mistake them for grass. Planting in September gives them the longest growing season. I’ve not done experiments, but suggest planting 6-8” (15-20cm) apart, and ½”(2cm) deep.
Around June, the foliage dies back to the underground bulb. (You may like to mark the position to avoid damaging them/overplanting.)
In September, growth resumes. If big enough, they’ll produce a flowering stalk in the summer. The flowers are sterile, but the ball of bulbils at their base can be used for propagation.
In June, the foliage dies back, but the stalk remains and releases the bulbils by breaking up in autumn.
The leaves can be used like leeks, or to add a garlic flavour to meats, stews, whatever.
The bulbils can be distributed on pizzas (remove husks).
The bulbs can be used as giant garlic – you’ll find them in ones and twos, not clusters as traditional garlic. I’ve just pickled some for the first time – yet to open. To get bulbs, not bulbils, break off the young flower heads (use them in cooking), so that the stalk dies back early. Lift in July/August - if your ground is solid, baked in the summer sun, try watering it to minimise bulb damage when digging them out.
You may try bunching the stalks to make insect homes.
Our mediaeval ancestors, and their predecessors, probably found these leeks and used them in their pots, part of the essential spring greens. As the plant’s only means of reproduction is by bulbils and division, this is the very same variety. It can’t be improved upon – for the same reason; and cannot breed itself out of disease susceptibility, so should not be grown in bulk, just isolated gardens.
If you fancy growing them, I can send some bulbils to UK addresses on receipt of a suitably stamped, addressed envelope: email me, antthehat at my hotmail.com address for information. Fresh stock is available in September, also the best planting time. If you've got any interesting edibles to offer in exchange, that would be great, but not essential.

The Chayote

Chayote - Sechium edule.
I got a job lot of these fruits for a song, so I thought I'd try growing them. A search on the internet suggested that the single seed inside this cucurbit's fruit might sprout if carefully cut out: I had no joy. They tried in their pots, but whether they didn't like the north facing windowsill in winter (the best place for me to keep my eye on them), or just didn't like being removed from the fruit, I don't know. But one fruit remained in its little plastic bag for some time, and started rooting and shooting. So I put it in a plantpot. As I write in mid April, it still looks reluctant. See the picture with the rotten fruit - taken before I removed the fruit and planted it up without - it had some roots trying to grow into the fruit, but rotting; there were still some healthy root starts waiting though. For some good pics of young chayotes, see http://www.greenculturesg.com/forum/index.php?showtopic=9734 Ultimately, I hope it will go romping up a bean frame, and if not produce fruits, then we'll gorge on shoots. I've none to offer, of course - just thought you may be interested.
PS - It died. It wasn't healthy when I removed the fruit, and just went downhill...