Weeds by definition are unwanted and wild. But what you may not know is that some of the main common culprits are actually edible and quite nutritious.
As with wild mushrooms, it’s very important to be sure of what you’re picking. But if you do your research, edible weeds can make a delicious addition to your diet.
Got some dandelions, for example? The yellow petals and young leaves can be used in salads, and the roots can be used as a coffee substitute.
Sydney-based nutritionist Catherine Saxelby said when compared with store-bought greens such as bok choy, rocket, basil, and parsley, many edible weeds were actually higher in important vitamins, minerals and nutrients.
Ms Saxelby said most edible weeds were high in phytonutrients and phytochemicals such as beta-carotene that help protect the body against disease, as well as vitamin A, vitamin C, and minerals such as potassium.
“Because they haven’t been bred the way commercial crops have been bred, they actually do seem to have higher concentrations of their natural vitamins, and minerals and phytonutrients,” she said.
Ms Saxelby said these days vegetables were bred for less bitterness, greater yield, ease of transport and bigger leaves.
“You never got that with the wild greens like dandelion and chickweed and purslane, which have just been left to grow themselves,” she said.
“So … not only are they free, and they seem to have a greater taste, a stronger more alive taste, they actually appear to be higher in certain nutrients.”
But edible weeds do have some nutritional drawbacks. Many wild leafy greens, like the sorrel varieties and purslane, have high concentrations of oxalic acid, which has been linked to kidney stones and is poisonous in very large amounts.
Oxalic acid is also present in store-bought foods including almonds, spinach, bananas and tea.
“So you can’t avoid it. But what you want to avoid is eating large amounts of it in one go,” Ms Saxelby said.
“[For example] if you ate a cup full of sorrel I would think that would be a very large quantity … half a cup of raw sorrel for your first time would be a good way to start.”
Doctors also recommend that women who are pregnant or breastfeeding limit their consumption of oxalic acid to small amounts.
Foraging growing in popularity
A growing interest in weed foraging has seen “edible weeds tours” spring up in many major Australian cities.
Susan Hutchinson, who takes urban foraging walks in Canberra, said learning the art of identifying edible weeds was rewarding on many levels.
“One of my favourite things about foraging is, it’s like having a new set of glasses, with a different kind of filter on them,” she said.
“You see food in all different places that you wouldn’t have otherwise anticipated … you would have walked straight by and not known.”
Ms Hutchinson also has a food blog that features her own gourmet recipes using edible weeds, such as wild brassica and potato gnocchi.
She began foraging as a cost-saving measure, but it has become another way to get creative in the kitchen.
“What has come from that is a really deep empowerment … with my own knowledge and ear around me I am able to find sustenance,” she said.
“And as quite a passionate cook, it’s not just sustenance. It’s fantastically delicious sustenance that you wouldn’t be able to buy on a supermarket shelf.”
Foraging safely
In order to forage for edible weeds safely, you need to be very sure that the weeds you are picking are what you think they are. To learn what is edible and what’s not, you need to do your research.
Reading a book on edible weeds, taking an edible weeds tour or studying reputable online sources are good places to start.
There are several Australian books on the subject, including a handbook by Melbournites Adam Grubb and Annie Raser-Rowland.
Mr Grubb, a permaculture consultant who has been running guided tours to educate people about edible weeds in Melbourne since 2006, said you should never eat anything you cannot positively identify.
“Although most of the plants that we call weeds, especially the annuals, are edible … there are some very toxic plants, some that will kill you,” he said.
“It’s really important to know beyond reasonable doubt that what you’re about to eat is what you think it is and … to know that it’s actually considered edible.”
The other thing to be aware of is the environment your weeds have come from. You need to consider whether the area you’re picking in is likely to be polluted and also whether the plants may have been sprayed with herbicides or pesticides.
“In terms of not eating things that have been sprayed, I think the safest place to eat plants from is your own backyard,” Mr Grubb said.
“Even then, if you’re in an urban environment … wash off any potential lead-containing dust or things that just blow around the city.”
To give you just a small taste of how many edible weeds are out there, here’s a list of 10 of the most common, and some ideas for how to use them:
1. Dandelion (Taraxacum officinale)
Dandelion is probably one of the most common and recognisable varieties of edible weeds and it’s also very versatile.
The yellow petals from the dandelion flower and the leaves can be eaten in salad, and the leaves can also be cooked and eaten like spinach.
The roots of the plant can also be dry-baked and used as a coffee substitute.
The leaves are an excellent source of vitamin A, vitamin K, calcium and iron. Mr Grubb said according to data from the US Department of Agriculture, it was one of the most nutritious leafy greens around.
“It depends how you slice the cake and crunch the numbers, but it always pops up near the top as one of the most nutritious plants that’s ever been tested,” he said.
2. Chickweed (Stellaria media)
Chickweed is often popping out at this time of year. It’s a little, delicate, herbaceous winter green, also rich in vitamins A, B and C, and a good source of Omega 6 fatty acid.
It can be cooked like spinach or used as a salad green, and Mr Grubb said since ancient times it has been used to treat itchy skin conditions as a topical ointment or a poultice.
“It has all these fascinating historical and cultural connections. It’s part of a seven-herb, spring rice porridge served in Japan,” he said.
3. Wild brassica (Brassica species)
Wild brassica comes from the same species of plant as broccoli, cauliflower and kale and is a good source of vitamins C and A.
Ms Hutchinson said while spring was the best time to go foraging for most leafy green weeds, the taste of brassicas actually improved in winter.
“Wild brassicas are one of my favourites,” she said.
“They do quite well into the winter … They get sweet in the winter time.
“In the summer they’re still there but they have a really strong, peppery bite to them, which can be nice if that’s what you like.
“But in the winter time, the little flower heads I love to eat. They taste just like broccoli.”
As well as the flower heads, the young leaves of brassicas can also be eaten cooked or in a salad.
4. Wild fennel (Foeniculum vulgare)
Wild fennel can often be seen growing by the side of the road, although this is not a good place to forage them because of potential contamination from passing cars.
The plants grow over 2 metres tall and the seeds and pollen can be dried and used to spice meats and other dishes. Both have an anise-like taste.
The fronds and stalks of wild fennel can be cooked and eaten in the same way as the store-bought variety and have a similar taste, although unlike the cultivated variety it has no bulbous base.
5. Wood sorrel (Oxalis)
Wood sorrel is a fine, herbaceous ground cover that is often mistaken for clover. It can be distinguished from clover by the shape of its leaves, which have a very definite heart shape. Clover, on the other hand, has leaves that are shaped like a tear.
This delicate leafy weed has a sour, citrus-like taste and is ideal for salads and for use as a garnish. However it wilts quickly and should be used soon after picking.
Wood sorrel in particular should not be eaten in large quantities because of its oxalic acid content, which can be poisonous in large amounts and has been linked to kidney stones.
6. Sheep sorrel (Rumex acetosella)
Like wood sorrel, sheep sorrel also has a citrus-style tang, but the leaves have a very different shape.
They are typically between 5 to 10 centimetres long, with a rounded tip and dog-like ears at the base.
Again, it’s great in salads and is sometimes cooked and used in soups.
But like wood sorrel, the oxalic acid content is high in sheep sorrel and so this is another edible weed that should not be consumed in large amounts.
7. Blackberry (Rubus fruticosus and relatives)
Blackberry is a weed of national significance and a real pest for farmers and local councils. But its fruit is delicious and can be found in abundance in late summer and early autumn.
Sydney nutritionist Catherine Saxelby said like all berry varieties, blackberries were a bit of a “super fruit”.
“They’re very high in vitamin C, they have a lot of folate or folic acid, which is a B vitamin needed to prevent birth defects,” she said.
“But their biggest claim to fame is their anthocyanins, which is their blue, black colour.
“There’s lots of research into those for anti-aging, maintaining your brain function as you get old, and as an antioxidant and anti-inflammatory.”
The leaves can also be fermented to make a delicious tea. In Canberra, Ms Hutchinson makes her own blackberry leaf tea, which varies in taste depending on how long the leaves have been fermented.
She said the young, pale green leaves were best for making tea.
“Bring them home, bash them up. This year I put them through the pasta machine but in the past I’ve used a rolling pin,” she said.
“Then pack them tightly in a sterilised glass jar, and forget about them.”
The leaves should be left for between two to six weeks to ferment. The tea will gather depth of flavour the longer it is left.
Try experimenting with fermenting times to find the right taste for your palette.
“After a designated period of time … pull them out, dry them out, crush them up, hey presto, tea for the year,” she said.
8. Nettle (Urtica urens)
Known for its stinging leaves, nettles might not seem like an obvious culinary choice. But once the stings have been disarmed, it’s highly edible and quite tasty.
Mr Grubb said the best way to disarm the stings was with almost boiling water.
“It takes a little bit of handling, because it’s known as stinging nettle for a reason. But it’s actually not that hard,” he said.
“If you use gloves to pick it, you just dunk it when you get home into some nearly boiling water for 30 seconds and that will disarm the stings. And then you can handle it and use it as you would other greens.”
Nettle is often used for teas, but Mr Grubb said he preferred to use it in soups and other dishes.
“It creates almost like a soup-like, savoury type flavour. I really like it as a tea,” he said.
“But that same culinary potential can be released in an actual soup … it has some almost seaweedy qualities to it. It can be used pretty much anywhere you use any other cooking green like spinach. It does lend its own character and I think it’s a very pleasant one.”
9. Purslane (Portulaca oleracea)
Purslane is a succulent native to Australia but also found in other parts of the world. It’s high in Omega 3 and has been the subject of much scientific research for this reason. Once again, this is a weed high in oxalic acid, so keep your quantities small.
“Purslane is one of my favourites. It’s a crunchy, slightly tart, lemony, semi succulent that grows at ground level and is a coloniser … It’s great cooked or in salads,” Mr Grubb said.
“We’ve also got a recipe … for a purslane tzatziki that tastes fantastic.”
10. Mallow (Malva species)
There are many different varieties of mallow, which are a genus of plants from the malva family.
“They can pretty much all be used interchangeably. Although they vary from core mallow, which can be 2 or 3 metres tall, to little ground covers,” Mr Grubb said.
Again, the leaves are best cooked and eaten like spinach, but can also be eaten as a salad green.
“They have a kind of umami richness … And they also, a little bit like okre, thicken things,” Mr Grubb said.
“Primarily [you eat] the leaves or you can also eat the seed head, which get called mallow cheeses. They’re like mini okres.”
This article originally appeared on the ABC.
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