Blessed Thistle

Blessed thistle is an annual herb that is straightforward to grow from seed and prefers warm, well-drained conditions. Seed can be sown indoors in early spring, or sown directly into its final growing position in late spring once the risk of frost has passed.

For indoor sowing, we recommend sowing one seed per pot to avoid disturbing the roots later on. Sow seeds just below the surface of the compost and lightly cover, then water gently. Keep the compost moist but not wet. Germination usually takes around 2–3 weeks, though it can be quicker in warm conditions.

If sowing outdoors, prepare a fine seedbed and sow thinly, covering lightly with soil. Thin seedlings once established, or transplant indoor-raised plants carefully, allowing a spacing of around 50–60cm between plants. Blessed thistle forms a substantial rosette and can grow quite large, so generous spacing helps ensure good airflow and healthy growth.

Blessed thistle prefers full sun and free-draining soil, and does not require particularly fertile ground. In fact, overly rich soil can encourage excessive leafy growth at the expense of flowers. Once established it is fairly drought tolerant, though young plants benefit from regular watering until well rooted.

Plants grow rapidly through late spring and early summer and usually flower in mid to late summer. As an annual, the plant completes its life cycle in one season, so if you’d like it to self-seed for future years you can allow some flowers to set seed. Otherwise, remove flower heads before they fully mature.

Blessed thistle has sharp spines, so take care when handling plants, particularly at harvest time.

Like its Asteracea cousins, Milk Thistle and Artichoke, Blessed Thistle is a bitter herb used to stimulate the flow and function of the digestive juices. Especially activating the saliva, gastric acid and liver the bitter sesquiterpene compounds come to the fore. Bitters like this, also found in wormwood, help to digest rich food and fats so its no wonder that blessed thistle has found a place in some famous digestif liqueuers, such as Bendictine. As a hot tea it has been used after a meal but also for a seasonal fever and, with some honey, to clear an infectious cough. It has also become popular for enhancing the flow of breast milk, although this area of herbalism requires further study. However, do not use if pregnant.

Harvest the aerial parts when it comes into flower early in the summer. Cut it into manageasble sized pieces and dry at 40C for a day. Store in airtight container.

To make a tea use 1-2 tsp in a cup of freshly boiled water infused for 15 minutes. Good taken with fennel and aniseed for all the above uses.

Useful as a poultice for surface wounds.

One potential downside of the sesquiterpene lactones is that they can act as mild to potent allergens for susceptible individuals. Reported reactions have ranged from varying degrees of allergic contact dermatitis all the way up to severe anaphylaxis requiring emergency treatment. Because these compounds are so widely distributed among the Asteraceae, cross reactions can easily occur. A person might become sensitized to the sesquiterpene lactones in one plant (e.g., Ragweeds – Ambrosia spp.) and subsequently will have a reaction to a novel species (e.g., Chamomile or Yarrow) in the family. This is why the herbalist should be cautious when using Asteraceae herbs with people who have a tendency toward respiratory and contact allergies or problems with chronic eczema / atopic dermatitis.