Scotch Thistle, Scotch cottonthistle
Onopordum acanthium
Family: Asteraceae or Compositae
What it is like
Onopordum acanthium is a BIENNIAL growing to 1.5 m (5ft) by 1 m (3ft 3in) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 6. It is in flower from July to September, and the seeds ripen from August to October. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. The plant is self-fertile. It is noted for attracting wildlife. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers dry or moist soil.
Height (m): 1.5
Where it is found
Waste places and arable land, especially on chalky and sandy soils, avoiding shade. Also found on slightly acid soils.
Europe, possibly including Britain, from Scandanavia south and east to Spain and W. Asia.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Flower buds - cooked. A globe artichoke substitute, though they are much smaller and very fiddly to use. Stems - cooked. Used as a vegetable, they are a cardoon (Cynara cardunculus) substitute. The stems are cooked in water like asparagus or rhubarb. They are best if the rind is removed. Leaves and young plants - cooked. They are harvested before the flowers develop and the prickles must be removed prior to cooking. The petals are an adulterant for saffron, used as a yellow food colouring and flavouring. A good quality edible oil is obtained from the seed. The seed contains about 25% oil.
Oil: Oil
Stem: this often intergrades into leaves.
Colouring: edible dyes
Medicine
Rating: 1
The flowering plant is cardiotonic. It is used in some proprietary heart medicines. The juice of the plant has been used with good effect in the treatment of cancers and ulcers. A decoction of the root is astringent. It is used to diminish discharges from mucous membranes.
Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.
Cancer: Used in the treatment of cancer.
Cardiotonic: A tonic for the heart.
Other
Rating: 0
The stem hairs are sometimes collected and used to stuff pillows. An oil obtained from the seed is used as a fuel for lamps.
Oil: Vegetable oils have many uses, as lubricants, lighting, soap and paint making, waterproofing etc. This does not include the edible oils unless they are also mentioned as having other uses.
Stuffing: Used in making soft toys, mattresses, pillows etc.
Attracts Wildlife: Plants noted for attracting wildlife
How it is grown
An easily grown plant, it succeeds in almost any ordinary garden soil. Requires a well-drained soil, preferably in full sun though it tolerates light shade. Prefers a slightly alkaline soil. Grows very well in poor soils, succeeding in hot dry situations and tolerating drought when it is established. A slow-growing plant. Hardy to about -15°c. A very ornamental plant, the flowers are very attractive to bees. Plants are prone to slug and snail damage. Often self-sows, sometimes to the point of nuisance, though the seedlings can easily be hoed out and can also be transplanted if they are moved whilst still small.
Propagating it: Seed - sow spring in situ. The seed can also be sown in situ in autumn. If the seed is in short supply then it can be sown in a pot in the greenhouse in the spring. Prick out the seedlings into individual pots as soon as they are large enough to handle and plant them out into their permanent positions in early summer.
Best place to grow: Cultivated Beds;
Habit: Biennial
Hardiness: 5-9
Growth: Slow
Soil: Light (sandy), medium, heavy (clay)
Shade: Semi-shade, no shade
Moisture: Dry, moist