Astrantia or masterwort, have been grown an a garden ornamental for many years yet until recently, this genus was not well known, at least in North American gardens. Although there are 10 species of Astrantia, there is only one main species grown in cultivation, A. major from central and eastern Europe. Less common in cultivation is A. carniolica, from the southeast Alps and A. maxima from southern Europe. In the wild, they grow on alpine slopes and dappled woodlands, usually on damp sites. In the garden, they are ideal for perennial borders, open woodland gardens and the wildflower garden. They will not tolerate drought conditions so dig plenty of organic material into the growing area to help maintain adequate soil moisture levels. They do not appear to be fussy about the soil pH. Astrantia are rated for USDA zones 5 to 9 but with extra winter protection, they have been known to survive in zone 4. Astrantia carniolica is the smallest species, reaching 60 cm, while A. major can reach 80 cm and A. maxima to 90 cm. All, especially A. major, are apt to self-seed so deadhead accordingly.
The three most popular species are A. major, A. carniolica and A. maxima
Although you would never say it, Astrantia are members of the Parsley family, Apiaceae. While at first glance, their flowers do not appear as an umbel (think of fennel or cow parsnip flowers), upon close inspection each ‘flower' is actually a small umbel surrounded by papery bracts. These bracts give the plants a long blooming season and make them ideal as a candidate for dried-flower arrangements.
Traditionally, the flowers of A. major and A. maxima were dull silvery-white. Astrantia carniolica is more colorful being pinkish-red. Astrantia major var. rosea also has pinkish flowers. Of particular merit is A. major subsp. involucrata whose bracts are twice the size of normal Astrantia, thus lend the ‘flowers' are much larger size. Like so many other garden ornamentals, Astrantia are currently enjoying a surge in popularity as a rash of new cultivars are being released. These cultivars are primarily selections of A. major with flowers that range from a more brilliant silver-white, through shades of pink to deep reddish-pink.
Among the selections of A. major subsp. involucrata are 'Shaggy' and 'Canneman'
Some of the modern-day white selections include ‘Star of Billion', ‘Star of Heaven', ‘Primadonna' and ‘Snow Star'. In the pink shades are ‘Rose Symphony', ‘Florence', ‘Tickled Pink', ‘Magnum Blush', ‘Buckland', ‘Abbey Road', ‘Lars' and ‘Lola'. Perhaps it is the reddish-pink shades that are currently the most popular. I must admit, many of these have flowers that are only subtly different from each other; they differ more in their ultimate plant height as some are shorter selections. These include ‘Ruby Cloud', ‘Hadspen Blood', ‘Moulin Rouge', ‘Star of Summer', ‘Roma', ‘Claret', ‘Star of Beauty', ‘Venice', ‘Ruby Stars', ‘Star of Fire', ‘Bloody Mary', ‘Ruby Wedding' and ‘Temptation Star'.
Above selections include 'Star of Heaven', 'Buckland' and 'Abbey Road'
Among the 'red' selections are 'Roma' and 'Star of Summer'
Among the A. major subsp. involucrata selections there is ‘Shaggy' (aka ‘Margery Fish') which is silvery-white and ‘Canneman' which is light pink. Finally, if variegated foliage is your thing, then Astrantia has two outstanding cultivars to fit that bill. ‘Sunningdale Variegated' has bold foliage with irregular but wide white margins while ‘Sunningdale Gold' has lovely yellow and green leaves.
Above are the variegated selections 'Sunningdale Variegated' and 'Sunningdale Gold'
Any of the above A. major selections, along with A. carniolica and A. maxima, are wonderful additions to the garden and will provide you with many weeks of blooms.
I would like to thank the following people for the use of their pictures: bootandall (A. maxima), bonniewong ('Sunningdale Gold' and 'Canneman'), DaylilySLP ('Star of Summer'), echoes ('Star of Heaven'), Galanthophile ('Sunningdale Variegated'), incomer44 ('Roma'), rebecca101 ('Abbey Road'), saya ('Shaggy') and stonetta (A. major).
(Editor's Note: This article was originally published on December 19, 2009. Your comments are welcome, but please be aware that authors of previously published articles may not be able to promptly respond to new questions or comments.)