Weeds not only flaunt human control, their very definition is a tricky thing to pin down. The standard definition goes along the lines of ‘a plant growing where it is not wanted’. The concept of a weed is a subjective one, more of a mental category than a botanical one.
The plants we call weeds come from all corners of the plant kingdom. It is remarkable then that so many of these plants which we curse, spray and hoe turn out to be not only edible, but often more nutritious than the cultivated crops they grow next to. They tend to be higher in vitamins, antioxidants and omega-3 fatty acids. In my local environment I can comfortably say that the vast majority of the herbaceous short-lived weeds are edible, and that’s probably true of most places. Outside of a farm or a food garden I don’t believe there is anywhere on the planet, other than a weed-scape, where such a large proportion of the plants can be eaten. The reasons why are fascinating, and the knowledge of which weeds are edible and how to use them, doesn’t hurt your health or financial situation either.
Although they are usually unrelated, so-called weeds do tend to share some common characteristics. In particular, those short-lived herbaceous plants — dandelion (Taraxacum officinale), fat hen/lambsquarters (Chenopodium album), nettles (Urtica species), purslane (Portulaca oleracea) and plantain (Plantago species) might be some familiar examples — tend to be adapted to growing in disturbed, bare soil. They put a lot of energy into reproduction: they produce masses of small, usually wind-blown or bird-carried seed. They don’t put much energy into their own longevity. So they tend to live fast, procreate a lot, and die young. You can think of them as rock stars of the plant world. (And, like the archetypical rock star, they tend to not obey the will of those that seek to control them.)
In ecological terms we have described pioneer species, those species adapted to disturbance. Many of the plants we call weeds originally evolved in tough conditions, where there is annual glaciation, periodic flooding, or severe fires – extreme events that leave exposed, bare earth. It’s in these devastated conditions that our weeds are at home. They germinate first and grow the fastest. And through these characteristics they have found important roles in re-establishing healthy ecosystems. With their rapidly growing root systems, they stabilise the soil and prevent erosion, they build soil organic matter and improve the hydrology. Once the weeds are established, longer-lived plants, less adapted to disturbance, germinate and the process of succession begins. The process may end in a grasslands, woodlands or forest, depending on the soil and climate. Indeed, the weeds create the conditions of their own inevitable demise – inevitable unless of course the disturbance recurs.
It’s in this ephemeral nature of weeds that the secret of why so many of them are edible lies. If their emphasis is on growing fast, any metabolic overheads such as toxin production could put them at a major disadvantage. So they tend to be quite palatable, and if you know what to look for (they aren’t bred for the human palate, so some knowledge of how to pick them helps) very tasty. Some prominent chefs are lately taking an interest.
It’s important to point out that edibility is a tendency, and certainly not a rule. Some of the most toxic plants known to humanity — hemlock (Conium maculatum) and castor oil plant (Ricinus communis) are good examples — are also pioneering weeds. If you eat any wild plant, identification and knowledge of its uses is paramount.
Their nature as plants adapted to disturbance also explains their long history with humans. Many of our crops are the cultivated ancestors of, or share the characteristics of, weeds. To grow annual crops we have to plough and expose the soil. This is a small ecological catastrophe for the soil each year (not so small when you consider the proportion of the globe’s best soils under cultivation). We also disturb the soil when we do earthworks, build buildings, create tracks and roads, and ironically, when we spray herbicide. Humans are the ultimate environmental disturbers, and the plants we call weeds are doing very well, thank you very much, out of it. Ribwort plantain (Plantago lanceolata) followed Neolithic farming so closely through Europe that paleoecologists use the fossil pollen record of it – not the crops – to trace the spread of agriculture in the region. In North America greater plantain (Plantago major) followed European settlement so closely it earned the name ‘white man’s footprint’.
It’s possible that we often blame the weeds, treat them as environmental vandals, when they are responding to damage we have caused, and in many cases are actively reversing it.
So they have adapted to us, and we in turn have learnt many ways to adapt to them. In particular, we’ve had a long time across many cultures to explore their medicinal characteristics. Many of the plants-we-call-weeds feature prominently in the earliest herbal texts, and are used to this day by medical traditions all around the world. Scientific study often backs up these tradition uses. For instance, the afore mentioned plantains (Plantago genus) have proven wound healing abilities when used topically, immune system boosting properties when eaten (at least in animal studies), and are a source of psyllium husk for digestion. Many of today’s weeds are also woven through folklore and cultures in fascinating and sometimes bizarre ways. Some have taken important ceremonial roles. Amaranth seeds were mixed with cactus syrup and human blood used to commune with the gods by the Incas, and amaranth flowers were buried with the dead in ancient Rome.
I discovered my first edible weed eight years ago, weeding the veggie patch and realising I had no idea what it was I was pulling out. I stopped half way and was able to identify the plant with the aid of a good book, and read about its uses on the web. It was the delicate and nutritious edible and medicinal plant chickweed (Stellaria media). It made it onto the lunch plate that day and wasn’t bad. I left the rest of the chickweed there, although in one sense, I did continue the weeding. A valued-weed is an oxymoron, and so by simple reclassification, chickweed became to me no longer a weed.
Environmentally, there could have been no meal with a lower impact than a fresh plant that grew itself, with no human labour, no transport or refrigeration, and no industrial chemical inputs.
Foraging has deeper roots in our nature than almost anything. So learning more seemed entirely natural. Eight years of research and eating weeds later, my partner Annie Raser-Rowland and I have condensed the best of this knowledge into a little book The Weed Forager’s Handbook: A Guide to Edible and Medicinal Weeds in Australia (Hyland House, 2012).
To give you a taster, here’s our eight of our favourite edible and medicinal weeds, all of which can be also be found in New Zealand, North America and Europe:
Amaranth (Amaranthus species)
This ancient grain alternative, prized by the Incas and Aztecs, is also a metropolitan weed and a fine cooking green, high in protein and minerals. Pick the growing tips and young, freshest looking leaves, and boil in water. Discard the water (amaranth contains oxalic acid) and serve with a little olive oil, salt and lemon as a side dish, or use anywhere you would use spinach.
Chickweed (Stellaria media)
This delicate cool season herb is a common volunteer in the veggie patch for it likes moist rich soils. The taste is very mild, and it is highly nutritious, being particularly high in iron, vitamins A and C and antioxidants. Trim just the tops off with scissors for the youngest leaves, which are good in salads, sandwiches and pestos. Look for the single row of hairs along the stem as an identifying marker to distinguish it from its many look-a-likes. Chickweed in an ancient remedy for rashes and other skin conditions, used as poultice or ointment.
Dandelion (Taraxacum officinale)
Perhaps the most iconic of all weeds, the dandelion is also one of the most nutritious plants on the planet, high in minerals, vitamins and antioxidants. All parts are edible, from the oh-so-decorative-in-a-salad yellow petals, to the root, which can be slow roasted and used as a coffee substitute. The freshest looking young leaves are lovely cooked, or make an excellent addition to salads for those that like bitter greens. Those antioxidants have cancer fighting power. Looks similar to the fortunately also edible cat’s-ear (Hypochaeris glabra and H. radicata).
Fennel (Foeniculum vulgare)
Fennel’s feathery foliage and yellow flowers can often be found alongside railway tracks and on other sloping land. Be sure you have fennel by sniffing for its intense aniseed aroma. The seeds and young foliage are both digestive aids and a good accompaniment to bean dishes. Fennel is a popular ingredient in teas, while the pollen is an expensive gourmet ingredient used in sweet and savoury dishes. Medicinally it is a digestive, and one often served after Indian curries coated in sugar.
Mallow (several Malva species)
A common sight with its dark green geranium-like leaves, mallow is a lovely mild-flavoured green. It is a relative of okra and contains the same mucilage fibre, which is good for digestion and can thicken soups and stews. Young leaves can be used in salads, but mallow’s flavour develops when it’s cooked. The young round seed heads can be used like tiny okras in stews and curries. They have powerful proven effects against gastric ulcers, and are calmative on sore throats.
Oxalis (Oxalis species)
Also known as soursob or wood sorrel, this clover-like plant is the bane of many a gardener due to its obstinate bulbs. However, they have a delightful lemony flavour and, used like a herb, can be added to any dish where this tang is welcome. Use sparingly as they are rich in oxalic acid. Not good for pregnant women. Eaten it can speed up wound healing.
Nettle (Urtica urens)
An easily identifiable weed; one can do it by touch alone, for they carry a fierce sting! If dried, or wilted in boiling water for 30 seconds, they lose this disagreeable feature, and are transformed into a highly nutritious cooking green. Nettles are extraordinarily high in calcium. Strip the young leaves from the stems and use as a spinach substitute, one of such a deep chlorophyll green that it’s easy to appreciate their reputation as a blood tonic. The dried leaves are used for tea, and nettle gnocchi with sage butter is a classic. The sting is used to treat arthritis, and the roots used for enlarged prostate. In other parts of the world the perennial Urtica dioca may be more prominent.
Purslane (Portulaca oleracea)
One of the first plants to colonise bare earth over the warmer months, this prostrate semi-succulent, with its jewel-like leaves and reddish stems is another nutritional superstar, and one valued in cuisines in both the Middle East and Mexico. Purslane has a crisp, tart flavour, and more omega-3 fatty acids than any other leafy green ever tested. Cooked, it excels in tomato dishes. Raw, it’s a great foundation for salads or tzatziki-style dips (we’ve a delicious recipe in the book). Yoghurt also binds up this plant’s oxalic acid.
Notes of caution
To reiterate, there are many poisonous plants, so proper identification is essential! Beware also of contaminated soil, and herbicide use. One way to learn more is to get a copy of the book, The Weed Forager’s Handbook: A Guide to Edible and Medicinal Weeds of Australia by Adam Grubb and Annie Raser-Rowland (see below) or a text for your region. We also have a weed gallery on the www.eatthatweed.com website, and run workshops in Melbourne, Australia.
…is available for $21.95, plus $3 postage within Australia
“If you eat, then this book is a must-have companion.”
~ Costa Georgiadis, host of Gardening Australia, from the foreword
Published by Hyland House, 2012 (Flexicover, 166 pages)
Adam Grubb is the founder of Energy Bulletin, a co-founder of the permablitz movement (www.permablitz.net) and a director and permaculture designer with Very Edible Gardens in Melbourne Australia. (www.veryediblegardens.com)
References for the book and by extension this article can be found at: