Contributed by Paul Orpello, Compton Horticulturist, Morris Arboretum

One plant that never ceases to impress me is the Geranium.  It has been a noteworthy garden perennial for over a hundred years. Personally, I don't know if it is the engaging floral display or the captivating primal scent. There is something about its magical sultry allure that draws me to put one in almost every garden design I create.  

Geranium, or cranesbill, has more than 400 species. Its botanical name comes from the ancient Greek, for crane, due to the resemblance of the fruit capsule to a crane's bill. Not to be confused with the genus Pelargonium, whose common name is also ‘geranium’ but used as an annual bedding plant. For the purpose of this article, I am referring to the genus Geranium or ‘hardy geranium’.

Hardy geraniums come in a variety of heights, forms, and colors.  There is one to suit almost any garden.  With dissect, or cut-leaf, foliage they are generally low mounding in shape and come in shades of pink, purple, or white.  Similar to most early summer flowering perennials, most species will benefit from a hard cut back immediately after the first flowering.  

Geranium sanguineum, bloody cranesbill, is a species that has rightfully gained its own attention with American gardeners.   G. sanguineum is 6-12” in height and can spread up to 18-24” in width.  It is tolerant of a wider range of soil conditions and temperatures than other Geranium species.  Blooming from May –August, these plants are superb in the front of the border or used in masses.  G. sanguineum boasts a fantastic free-flowering floral display and excellent mounding growth habit.  Though its rich magenta colored flowers can be intimidating to some, I find their flamboyantly flashy flowers absolutely outrageous if paired properly with the right combination of plants.  Their exceptional drought tolerance keeps them on my list of essential full sun edging plants.

The variety of G. sanguineum cultivars in the trade can make it a bit overwhelming.  While the straight species is an excellent garden worthy plant in its own right, there are a few cultivars I find extremely useful in the garden.  G. sanguineum ‘Album’ offers a welcomed white flower form. Try “newer” cultivars like ‘New Hampshire Purple’ and ‘Tiny Monster’.  Their larger flower size, aggressive growth, and purple flower shades are an extremely welcomed improvement.    Geranium x ‘Dilys’, an interspecific hybrid (G. sanguineum x G. procurrens), touts the same great characteristics as the G. sanguineum cultivars with increased spreading and weaving capabilities creating  a seemingly endless free-flowering summer display.

To find Geranium sanguineum at Morris Arboretum, visit the Pennock Garden in the heat of the summer.  A cultivar I have used with great success; ‘John Elsley’, named after the horticulturist of Wayside Gardens, can be found interplanted amongst Lavandula x ‘England’.  This splendid combination is just one of many featuring geranium here at the Morris Arboretum.  Visit our displays for inspiration and try a Geranium you favor in your own garden this season! Happy gardening…