Latin Name: Sonchus asper
Common Names: Prickly sow thistle, spiny sow thistle, sharp sow thistle, rough milk thistle
Season: Early spring
Edible: Yes
Flavor: Good
Medicinal and nutritional value: Vitamin rich, antioxidant strong, liver and kidney purifying
Identification difficulty: Beginner
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| The leaves of this plant are at a good stage for harvest |
Despite the texture, prickly sow thistle is one of the edible wild plants I look forward to the most every spring.
If you can work around the prickles, which is easy enough to do when planning dishes that need to be pureed (like sauces and soups), you are rewarded with a wonderfully rich leafy green. The flavor is generally very mild with only a slight bitterness, comparable to swiss chard or belgian endive, to add complexity. Most everyone who eats leafy greens will enjoy properly prepared prickly sow thistle.
Perhaps even better, prickly sow thistle is extremely common
Nutritional & medicinal benefits
The sow thistle family (Sonchus) is one of the ones where a significant amount of research has been done into nutrition and potential medicinal benefits. Sow thistles have long been accepted as health foods, associated with liver and kidney purification.
Recent studies have shown that the sow thistles, particularly the prickly sow thistle, are antioxidant powerhouses. Antioxidants have been shown to reduce the effects of aging, both on the body and mind. They also lower your cancer risk.
While antioxidant extractions are available in pills, syrups, etc., studies show that the best way to gain the positive effects of antioxidants might simply be to incorporate a large number of antioxidant-rich foods into your diet.
All three sow thistles were found to be rich dietary fiber and in vitamin E, though smooth sow thistle (Sonchus arvensis) had the highest concentrations. Like most leafy greens, sow thistles have a lot of valuable minerals, including potassium, calcium, magnesium, iron, zinc, sodium and selenium. Smooth sow thistle is the best of the 3 for potassium, common sow thistle has the highest concentration of iron and prickly sow thistle offers the most calcium.
As an added bonus, sow thistles DO NOT have large amounts of oxalic acid, even though they exhibit red coloration. They contain less than 10% of the oxalic acid found in spinach or swiss chard, for example, and less than 5% of the oxalic acid in purslane.
To learn more about the antioxidant properties of prickly sow thistle, check out this article from the National Library of Medicine.
To learn more about the nutritional qualities of the sow thistle genus, please read this article from the National Library of Medicine.
History as a food crop
There are three, common, wide-spread sow thistles: Common sow thistle (Sonchus oleraceus), prickly sow thistle (Sonchus asper) and smooth sow thistle (Sonchus arvensis). They are native to Europe, particularly the Mediterranean regions. They are now found throughout temperate North and South America, Australia and New Zealand, the Middle East, and much of Asia and Africa.
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A good-sized haul of prickly sow thistle leaves,
ready to cook and eat |
Our earliest record of sow thistles as a food comes from the ancient Greeks, who considered it to be strengthening, and used the non-prickly varieties in salads, especially during winter time when greens were scarce.
Europeans in the middle ages valued the sow thistles for animal feed. The name "sow thistle" comes from farmers feeding the plant to sows with piglets; it was believed that this plant increased lactation.
As traditional agriculture became the standard in Europe and European colonies, like the U.S., sow thistles came to be regarded as common weeds, and a great deal is spent to eradicate them.
But that is not always the case in areas where sow thistles have spread.
As European agricultural practices spread with colonization, many native species of plants, which were essential food sources for the native peoples, were wiped out. Eurasian plant species had evolved a centuries-long history of competition, due to exposure to other plant species spread via trade routes. As a general rule, these plants could out-compete native species, which is why dandelions, plantains, sow thistles and others are considered common weeds today.
But many native peoples have embraced the "weeds" traditional agriculture rejects, and have used them to supplement or replace native plants that have been decimated. Sow thistles in particular are consumed by the Māori of New Zealand and the by the native peoples of the rural Brazilian rainforest regions.
In addition to the three most wide-spread sow thistles there are many regional species, especially in Africa and some hype-local species in places like the Canary Islands, some of which are used for food.
