Tuberous Thistle
Cirsium tuberosum

Family: Asteraceae or Compositae

What it is like

Cirsium tuberosum is a PERENNIAL growing to 0.6 m (2ft). It is not frost tender. It is in flower from June to August, and the seeds ripen from July to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees, flies, Lepidoptera (Moths & Butterflies), beetles. The plant is self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers moist soil.

Height (m): 0.6

Where it is found

Damp grassland on calcareous soils.

Western and central Europe, including Britain.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 3

Root - cooked. It can be stored overwinter. A slight bitterness but acceptable, it makes a reasonable cooked vegetable. Sometimes, however, the root seems to be very aromatic and is then less than pleasant. The root is rich in inulin, a starch that cannot be digested by humans. This starch thus passes straight through the digestive system and, in some people, ferments to produce flatulence.

Oil: Oil

Root: includes bulbs, corms, tubers, rhizomes etc.

Medicine

Rating: 0

Other

Rating:

The seed fluff is used as a tinder. The seed of all species of thistles yields a good oil by expression. No details of potential yields etc are given.

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.

Tinder: Used for starting fires. See also Kindling.

How it is grown

An easily grown plant, succeeding in any ordinary garden soil in a sunny position. Plants are tolerant of considerable neglect, though they produce much better roots when given a good soil and some attention.

Propagating it: Seed - sow early spring or autumn in situ. Germination usually takes place within 2 - 8 weeks at 20°c. Division in spring or autumn. Very easy, larger clumps can be replanted direct into their permanent positions, though it is best to pot up smaller clumps and grow them on in a cold frame until they are rooting well. Plant them out in the summer or following spring.

Best place to grow: Cultivated Beds;

Habit: Perennial

Hardiness:

Growth:

Soil: Light (sandy), medium, heavy (clay)

Shade: No shade

Moisture: Moist

Things to keep in mind

Its other names

Local names

Synonyms

Carduus bulbosum. Carduus tuberosus. Cnicus tuberosus.