By Kolton Boyer
Reiman Gardens
Iowa State University
The cardoon (Cynara cardunculus) originated in North Africa but was found to be edible by the Greeks who grew cardoons as an agricultural crop. With the spread and establishment of the Roman Empire, cardoons were also grown and eaten by many other people living in the Mediterranean region. By the 18th century, the Quakers introduced the plant to North America. Today, the cardoon is used extensively as food and a landscaping plant.
Cardoons are members of the aster family (Asteraceae) and relatives of the artichoke possessing a similar bittersweet taste. They are perennials found in USDA Hardiness Zones 8-14. However, they can be grown as annuals in Zones 4-5. Cardoons prefer clay to coarse-textured, rocky soils, minimal water and favor full sun, but will tolerate partial shade.
The flower resembles a thistle; large in size and pink to purple in color while the foliage is gray to green. By the end of the growing season, cardoons will reach a maximum height of 3-7 feet and up can grow up to 6 feet in diameter. The cardoon is excellent planted in mass, and has also been showcased successfully as a specimen plant. However, homeowners in Zone 5 should be aware that it is quite difficult to have blooms form on cardoons.
Early in the growing season, maintenance for this plant is relatively simple. However, as the seaosn continues, achieving the desired look for this plant can become a chore. For example, some gardeners prefer to allow cardoons to spread while others favor staking to achieve maximum vertical growth.
View a collection of cardoons in the Margaret E. Penkhus Campanile Garden at Iowa State University’s Reiman Gardens. The rough, hard texture of the cardoon leaves create a great contrast to the gentle curves of the flower beds in this garden.
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