Silybum Milk Thistle Info: Tips For Planting Milk Thistle In Gardens
By: Liz Baessler
Milk thistle (also called silybum milk thistle) is a tricky plant. Prized for its medicinal properties, it is also considered highly invasive and is being targeted for eradication in some areas. Keep reading for information about planting milk thistle in gardens, as well as combating milk thistle invasiveness.
Silybum Milk Thistle Info
Milk thistle (Silybum marianum) contains silymarin, a chemical component known to improve liver health, earning the plant its status as a “liver tonic.” If you want to produce your own silymarin, milk thistle growing conditions are very forgiving. Here are some tips for planting milk thistle in gardens:
You can grow milk thistle in gardens with most types of soil, even soil that is very poor. As milk thistle is often considered a weed itself, virtually no weed control is needed. Plant your seeds ¼ inch (0.5 cm.) deep just after the last frost in a spot that receives full sun.
Harvest the flower heads just as the flowers start to dry and a white pappus tuft (like on a dandelion) begins to form in its place. Place the flower heads in a paper bag in a dry place for a week to continue the drying process.
Once the seeds are dried, hack at the bag to separate them from the flower head. The seeds can be stored in an air-tight container.
Milk Thistle Invasiveness
While safe for humans to eat, milk thistle is considered toxic to livestock, which is bad, as it often grows in pastures and is hard to get rid of. It is also not native to North America and considered highly invasive.
A single plant can produce over 6,000 seeds that can remain viable for 9 years and germinate at any temperature between 32 F. and 86 F. (0-30 C.). Seeds can also be caught in the wind and carried easily on clothes and shoes, spreading it to neighboring land.
For this reason, you should really think twice before planting milk thistle in your garden, and check with your local government to see if it is even legal.
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How to Use Milk Thistle for Liver Detox
Disclaimer: Results are not guaranteed*** and may vary from person to person***.
Milk thistle, a member of the Asteraceae family of plants from which daisies and sunflowers belong to, has been used for over 2,000 years to treat gallbladder and liver problems. It is the number-one herb (a weed, actually) used to detoxify the body, in particular a liver detox.
It has anti-inflammatory and antioxidant properties, and a milk thistle liver detox is used to help increase bile production and create better digestive function.
5 Favorites: Garden-Friendly Thistles
Legend has it that the thorny thistle once saved Scotland from a marauding Norse army, a feat that earned this tenacious plant its status as a Scottish national symbol. But these days it’s staging an invasion of its own, causing people all over the British Isles, and elsewhere, to declare war on this invasive weed.
More’s the pity in my opinion, because I rather like the prickly beauty of thistles. Luckily there are some garden-friendly varieties, that with proper care, won’t run amok. Here are five of our favorites:
(Invasive) Scots Thistles
Above: Photographer Francisco Gonzalez captured this quintessential image of Scotland: Scottish thistle in the Highlands. But throughout the world, invasive Scots or cotton thistles and their cousins threaten native species. Prairies and grasslands in America and Canada are being overrun, and in Australia the problem was so bad that Parliament imposed heavy penalties on those who did not control thistles on their land.
Above: Misty globe thistles (Echinops ritro) by Isidre Blanc via Wikimedia.
The gentler cousin to the Scottish thistle, non-invasive globe thistles (Echinops ritro) are ideal for the garden. With deep blue or violet orbs perched on silvery stems that are from 2 to 4 feet tall, globe thistles provide a striking architectural and textural element to the garden. Drought resistant, these hardy perennials are also easy to care for. Bees, butterflies, and lady bugs love them too. Hardy in growing zones 3-9. Globe thistles are readily available at most garden nurseries. A 5-Inch Pot Of Blue Glow Globe Thistle is $8.99 at High Country Gardens.
Giant Cotton Thistles
Above: A giant cotton thistle in Prague. Photograph by Karelj via Wikimedia.
Giant cotton thistle (Onopordum acanthium) was prized during the Middle Ages for its herbal properties, and by the poor who used its fluffy “down” to stuff mattresses. At from 10 to 15 feet high with a 5-foot spread, this dramatic biennial is not for small gardens. It benefits from staking and from stony soil (which provides better support for its roots). But note: Giant cotton thistle is invasive. To prevent the seeds from scattering to the wind, it is important to cut the heads off after flowering. You can also see that, with all those spikes, it should only be handled by gloved hands.
Above: Cirsium rivulare ‘Atropurpureum’ by Jean Jones.
Magenta heads atop long, leafless, and spike-less stems make ornamental plume thistle ( Cirsium rivulare ‘Atropurpureum’) an excellent garden choice. Rivulare literally means “growing by a stream,” and this perennial prefers moist, yet well-drained ground fertile, slightly acidic soil, and full sun. Cut back after early summer flowers to promote another flowering, and then to the ground after the last bloom in the fall. Though popular in Europe, this Cirsium is pretty rare stateside, so you’ll get points for originality with this one. A 1-Gallon Pot Of Cirsium Rivulare ‘Atropurpureum’ is available at Far Reaches Farm seasonally for $16.
Above: A globe artichoke in flower in South Africa. Photograph by Marie Viljoen. For more, see My Mother’s Garden in Constantia.
Last year, Michelle discovered that artichokes are members of the thistle family, Asteroideae, as well. (See A Thistle That Won’t Misbehave.) Though its wild counterpart artichoke thistle is invasive, stately globe artichokes (Cynara cardunculus) and their cardoon cousins make a dramatic statement in the garden, and, of course, can be eaten as well. (With cardoons, you eat the stem, which is said to taste like a celery artichoke medley.) Artichokes and cardoons prefer lots of sun and rich, well-drained soil. To build up a plant’s strength, during the first year cut off the heads as soon as they appear. Replace the entire crop every four years. For more information, refer to this extremely thorough article from The Daily Mail.
Above: Photograph by Erin Boyle.
Not really a thistle at all (actually a distance relative of the carrot family), sea holly (Eryngium), is often considered a worthy stand-in for thistles. I love it for my seaside garden, where it endures not only drought and poor soil, but also salty air. About the only care it requires is deadheading to encourage additional blooms.
N.B. Thistles and sea holly also dry well for use in winter arrangements and crafts. One of my favorites is Erin’s Black Thistle Bouquet.
Finally, get more ideas on how to successfully plant, grow, and care for thistle with our Thistle: A Field Guide.
Finally, get more ideas on how to plant, grow, and care for various perennial plants with our Perennials: A Field Guide.
By Monty Don for MailOnline
Updated: 22:30 BST, 26 June 2009
It can be hard to see a thistle as anything other than a painful weed, and they are all being topped right now by farmers as part of the constant attempt to eradicate them from fields.
The gardener can learn from agriculture in this. If you want to get rid of them, then cutting them just as they flower will do much to weaken them. But do this too early, and they will return with vigour let them seed, and you are guaranteed more plants than ever next year.
The old rhyme is, 'Cut thistles in May, they'll grow in a day/Cut them in June, that is too soon/Cut them in July, then they will die.'
The best time plant thistles is in autumn or early spring, before the they starts growing again
The common weed in my garden is the spear thistle, Cirsium vulgare, which develops spines like needles and has a characteristic 'Scottish' thistle flower.
Although the farmer may not cut it until July, the gardener wants to get it out long before then, even if it comes back for a second go - when young it can go on the compost heap, but as soon as the spines harden up, it must be burnt or finely shredded.
Its cousin, the creeping thistle, Cirsium arvense, has a soft, sappy stem that tends to snap off when you try to pull it up. It gets in under the hedges of my garden, spreading by lateral roots as well as by seed.
At this time of year we also get a lot of sow thistles - Sonchus asper and Sonchus oleraceus - which are sappy and easy to pull up in well-cultivated soil and then compost.
The dwarf thistle, Cirsium acaule, is the one with an incredibly spiny rosette, which pricks your behind when you sit on the grass.
Wherever they spike you, thistles hurt, and of course it's even more of a pain if you do find your garden filled with them. But if that is the case, you can take comfort in the knowledge that your soil is good, because thistles mostly like a deep, rich loam.
And that is not the only positive note. In fact, rather than denigrating thistles as weeds, my real aim here is to praise their presence. Thistles are beautiful and dramatic, and every garden should have them. The secret, of course, is to choose your thistles with care.
I know there are gardeners who would regard the giant cotton thistle, Onopordum acanthium, as a weed, but I love it and carefully dig up the seedlings wherever they pop up in clusters, and then redistribute them for better effect in our borders.
They are certainly intrusive, growing to at least 10ft and often 15ft, with a spread of 5ft. But they are among the most dramatic garden plants, with huge grey leaves coated with a milky down, fringed with wicked spikes and great candelabras of flowering stems.
The plant needs to be staked in firmly, otherwise it will be brought crashing down in the first summer gale. It is biennial, and the most reliable way to get plants is to dig up unwanted seedlings from a friend's garden.
The best time to do this is in autumn or early spring, before the thistle starts growing again.
When the plant has flowered, it rapidly becomes a spectacular skeleton, which looks fine if supported but makes weeding a nightmare as the spikes become spikier and more painful with age.
Cirsium rivulare 'Atropurpureum' delights in boggy conditions or heavy clay soil. It grows to about 4ft tall, and has plum-coloured flowers and leaves that are hardly prickly at all, which makes it a very borderfriendly plant - although it does have a habit of suddenly collapsing and then not reappearing the following year.
It is also sterile and will not produce seedlings, so it is a good idea to lift it every couple of years and take some root cuttings.
The globe thistle, Echinops ritro, is a tough herbaceous perennial, happiest in poor soil as long as it gets some sun. Although its leaves are very prickly, the mauve pom-pom flower heads justify the odd painful encounter.
The globe thistle rapidly makes a big clump and needs rigorous reduction every year or two. But I love its perfectly round heads, which bear a remarkable resemblance to machine-tooled steel just before the buds open.
Echinops bannaticus 'Blue Globe' has darker blue flowers, while those of E. bannaticus 'Taplow Blue' are a more intense blue. E. exaltatus is huge, growing to 7ft, with silvery-white flowers.
Perhaps the most popular thistle is the giant sea holly, Eryngium giganteum, though it is not really a thistle at all - despite its armoury of spikes and prickles - but a distant cousin of the carrot.
It is commonly known as 'Miss Willmott's Ghost' because Miss Willmott, an Essex gardener of a century ago, apparently went round secretly - and rather irritatingly - scattering its seed in other people's gardens.
It is distinctly silver, though tinged with the blue that so marks sea hollies, and leaves a dried husk of itself all winter with a seed head not unlike a teasel, Dipsacus fullonum, another incredibly spiky plant and one that loves wet ground.
Eryngium giganteum 'Silver Ghost' is smaller and more silvery white. It is a short-lived perennial, which means that it is lucky to flower twice.
All eryngiums like very well-drained, poor soil.
Most thistles are edible - they include artichokes (Cynara scolymus) and cardoons (Cynara cardunculus) - and many have been grown for medicinal purposes.
Cardoons are one of the best of all foliage plants, if you have space for them, as they add great drama to a garden. From February, they start to sprout extravagantly scalloped grey leaves, which grow steadily from large to enormous during summer.
The thistle flowers are carried on huge stalks that are as thick as a wrist and reach 10ft tall in a mature plant.
I leave these all winter or until they topple under their own weight, and the seed heads open out into a wonderful cottony fluffiness right at the end of the year. Their real home is in the vegetable garden. It is a crop that has gone out of fashion, yet the flavoursome blanched stems can taste like a combination of celery, chard stem and artichoke flavours.
Artichokes are very similar to cardoons, but are smaller and more tender, and whereas a cardoon will (weather permitting) happily grow on for decades, artichokes rapidly lose vigour and the ability to produce flowerheads after three or four years.
They are happier with hotter, well-drained conditions, and in my experience the more sun you can let them have, the better they'll grow. Nevertheless, they respond well to plenty of manure and moisture.
The trick is to replace the crop entirely every four years - as one does with strawberries - by ditching a quarter of your plants every year.
Like cardoons, they grow very easily from seed, although side shoots are a more reliable means of producing vigorous, healthy new plants.
For the first year you should cut off any flower heads as soon as they appear, to allow the plant to build up strength. This means having a line of plants in the vegetable garden doing nothing for a year, but it is worth it.
Cutting the first and largest flowering buds provokes the plant into producing more smaller ones, which tend to be tastier, and this is where growing your own crop really comes into play. =
Half a dozen plants will give a plentiful harvest of golf ball-sized artichokes, which can be cooked and eaten simply sliced in half and are truly delicious.
How To Care For Milkweed Plants
Growth habit: Most milkweed species are clump-forming. Common Milkweed is a single stemmed variety.
Staking: Milkweed plants have sturdy stems - no staking needed.
Watering: Swamp Milkweed varieties need either a naturally moist environment or regular watering. Whorled and Common Milkweeds, as well as Butterfly Weed, are suited to a dry environment.
Fertilizing: Milkweed does not require fertilization. This native plant performs well in poor soils.
Mulching: You may mulch milkweed with leaf litter or fine-chopped bark mulch if you're trying to control weeds. Dry-soil loving milkweeds, like Butterfly Weed, may not appreciate the water retaining qualities of mulch.
Trimming & Pruning: None needed.
Thistles: A High-Nutrient Weed
Thistles are a bane of picnickers and campers. Who hasn't trodden on the sharp, unforgiving spines of a thistle when out and about barefoot in grasslands? For many people, relationships with thistles have generally been painful and irritable, but now you can get your own back!
One of the great things about thistles is that every single species is edible, so this is great news for foraging beginners! Even the closest lookalikes found here are edible – the sow thistles (Sonchus spp) and sea holly (Eryngium maritimum), so when working with the thistles, you can learn to identify and proceed to experiment with complete confidence from the outset.
We have at least 14 species of thistle growing wild in the UK, mostly from the Cirsium (aka plume thistles) and Carduus genera. Thistles are found in numerous settings all over our islands and can be a useful soil barometer. Often their presence signifies that the land is fertile, and in many instances, neglected.
I eat from a number of different species. These are: creeping thistle (Cirsium arvensis), spear thistle (C.vulgare), woolly thistle (C.eriophorum), marsh thistle (C.palustris), and welted thistle (Carduus acanthoides syn C.crispus). As you will discover, plants that have spines to offer protection against predators, have no real need for bitterness.
It's almost impossible to misidentify a thistle. One of the easy-to-spot botanical differences between thistles and their numerous relatives in the daisy family, is that the overlapping bracts (involucre) found directly below the flowers of thistles, are always spiny. Simple!
The leaves of the numerous species will differ in size, shape and the density of spine coverage. Most have stiff spines on the margins, but some have soft prickles. You need to discover for yourself which are the more tactile!
When in flower, most thistles produce a lovely purple / mauve bloom, but some species are known for their yellow inflorescence (cabbage thistle – Cirsium oleraceum and the Carline thistle – Carlina vulgaris).
In all of the thistles, flowers give way to copious amounts of fluffy hairs (pappus) attached to their tiny fruits, superbly designed for air-borne dispersal. A distinguishing feature between the two main genera is that Cirsium spp produce feathered pappus hairs, whereas Carduus spp only have simple pappus hairs.
Creeping thistle produces dense spines on its leaves, but very few spines or hairs on the flowering stems. Spear thistle has large, deeply-lobed leaves with large spines at the margins, as well as hairy, spiny stems.
Marsh thistle looks somewhat like spear thistle at an initial glance, but without the large spines and leaf lobes, and usually with a thin, red, leaf margin. Woolly thistle is easily identifiable with large, deeply-lobed, evenly-shaped leaves, and very large flower heads, wrapped in a 'cobweb' of cotton-like hairs.
This particular species is the largest wild thistle I use, although if you have milk thistle (Silybum marianum) growing in your plot, you can use that too, but you will need good gloves to protect yourself from its long spiny flower heads! Eating milk thistle chokes would of course prevent you harvesting the exceptional liver-supportive medicine found in the seeds.
Where to find thistles
Creeping thistle will grow in all manner of waste-ground, grasslands, verges and field edges. I also see a lot of spear thistle in similar habitats, although when found in grassland, it's not as abundant as the creeping species. The root systems explain why spear thistle has a tap root, whereas creeping thistle grows on rhizomes.
The marsh thistle, as its name alludes to, likes damp conditions such as fens, marshes, canal tow-paths and riversides. Woolly thistle is a little bit more selective in its choice of soil and setting, preferring calcareous ground. It too enjoys grasslands. Welted thistle can be found all over the UK, especially loving clay soils.
Go prepared! Stiff gloves and a knife are required. Harvest the best leaf mid-ribs in spring when growth is plentiful and quick. Your specimens will be tender and sweeter.
Flowering stems will appear from late spring through into autumn. I only consider harvesting from plants whose flower buds are yet to really begin unfurling. Flower buds (chokes) are available all summer.
Nutritional value of thistles
In Portugal, a number of thistle species are still collected in spring and sold at markets. A recent academic study highlighted the nutritional value from eating thistles. The findings are contained within 'Ethnobotany In The New Europe' by Manuel. P de Santayana et al (Eds), published June 2010.
In the study, researchers noted the wide range of thistle species collected, and concentrated on the nutritional value of one particular thistle (Scolymus hispanicus – Spanish or golden thistle). This plant is collected by villagers in various areas of the countryside. Bunches of the stripped leaf mid-ribs are sold and bought in a number of markets in different areas.
Levels of certain nutrients were analysed and compared to some commonly consumed vegetables. Their findings show that the thistle contained consistently higher levels of important major nutrients than some of our commonly consumed cultivated vegetables.
Weight for weight, thistles come out higher in fibre, protein, phosphorus, magnesium, calcium, copper, zinc, and other nutrients.
Is it likely that the thistles found wild here will be similarly endowed with a range of important vitamins and minerals? I'm more than happy to work on the assumption that this will be the case. Many other wild plant species are known to contain high concentrations of important nutrients.
How to use thistles
Preparing thistles is pretty easy. Simply choose the most tender specimens. If using the petioles, then cut and strip all the spines off, before peeling the outer, fibrous layer from the stalk. Use raw as crudités, pickle or ferment them, or chop into salads and serve them with a tangy vinaigrette. If cooking, they don't require long!
Preparing the stems is similar, but they are hollow. These can be used in similar ways to the petioles, or you can stuff them, roast them, and braise them.
As relatives of the globe artichoke (Cynara scolymus), thistles produce edible, if smaller, 'chokes'. These are the crunchy, immature bases, or capitulum, of the composite flower-head. As you would do with globe artichokes, peel away the bracts to get to the prize. I only choose the largest wild species for this.
Thistles are included in my new foragers playing cards, which feature 52 colour photos of temperate zone edible wild plants. They are ideal presents for plant lovers in any temperate climate! The decks are available, along with my new 2016 wild plant guide calenders, from [email protected]