I once had a friend tell me, “I am adding more geums to my garden – they are so lovely and delicate. And now they come in more colors than ever.” So I nodded and smiled and kept my mouth shut because I realized that I actually didn’t know what a geum was.
After searching the Internet I found that I knew these flowers well – I had seen geums a thousand times. The native Geum trifolium is what I knew as prairie smoke. But I still didn’t know much about cultivated geums, which are also called avens.
Turns out there is a plant wizard up in northern Illinois who is re-imagining geums. I just had to take the journey, talk to him and learn from his wisdom.
Brent Horvath, president of Intrinsic Perennial Gardens, Inc., a wholesale nursery in Hebron, Illinois, selling new geum cultivars, which he has named after cocktails. Why cocktails? “There were already a few in the trade with cocktail names like ‘Double Bloody Mary’ and ‘Lemon Drops’, and when we looked at ‘Mai Tai’ to describe it, it really fit the color of the drink,” he explains. “Overall, the flower colors lend themselves to so many tropical drinks and their ingredients. We even have drink recipes in our catalog.”
The Cocktail Series includes Geum x ‘Alabama Slammer’, ‘Banana Daiquiri’, ‘Cosmopolitan’, ‘Gimlet’, ‘Limoncello’, ‘Mai Tai’, ‘Sangria’, ‘Sea Breeze’ and ‘Tequila Sunrise’. In 2014, he will introduce three more: ‘Dark and Stormy’, ‘Wet Kiss’ and ‘Spanish Fly’. These new geums start blooming in late April or May and continue for about four weeks or more. The short clumping plants reach around 10 inches tall and wide with the stems and blooms around 18 inches tall.
Horvath has been breeding geums to be longer-lived than the older hybrid varieties, to be more adaptable to Midwestern conditions, to include more colors and to be more floriferous.
How did Horvath decide geums needed to be improved by his magic touch? “We were growing a few, and I noticed that Geum ‘Georgenberg’, which had kind of a tangerine-apricot color, had rebloomed. And I thought that was a good trait to try to breed more into other colors.”
He began interbreeding species and cultivars, including Geum montanum (which is an alpine plant with glossy foliage and yellow flowers), Geum coccineum ‘Borisii’ (an orange-blooming plant), Geum rivale (a wetland plant), as well as the cultivar Geum chiloense ‘Flames of Passion’.
“Also at the time, Scabiosa x ‘Butterfly Blue’ was really hot; it had that heavy rebloom. So I thought that if we could get a geum like that, it would be really cool. My initial crosses came up with ‘Tequila Sunrise’ and ‘Mai Tai’, and so those were more about unique colors than rebloom.
“The majority of my breeding is open-pollinated,” he continues. “So what I do is take plants or seedlings I like, and I will grow them together closely so I can let the bees do the majority of the work.” This is the old-fashioned way to do it and the method he prefers (although he does some cross-pollinating by hand as well). Hybrids are created when the pollen of one plant gets put on the female part, or the style, of another plant, resulting in a hybrid seed.
“Initially I started with a semi-double, golden yellow with some orange and red on the edge. And then I got ‘Mai Tai’ and ‘Tequila Sunrise’ from that,” Horvath explains. ‘Tequila Sunrise’ was introduced to growers in 2009. “Then from ‘Mai Tai’ and ‘Tequila Sunrise’, I got ‘Alabama Slammer’, which was a sport of ‘Tequila Sunrise’ with more orange and red in it. Then ‘Cosmopolitan’ and ‘Wet Kiss’ came out of ‘Mai Tai’ – one is a darker form and one is a lighter form, and both were sports.” (A sport is a mutation or part of a plant that is significantly different from the rest of the plant. Sports may differ by foliage shape or color, flowers or branch structure.)
Brent notes that ‘Wet Kiss’, ‘Mai Tai’ and ‘Cosmopolitan’ are all closely related in their shades – vermillion red with pink and orange undertones with red stems and calyxes (the part under the petals). So even after the petals fall off you have a red stem and red seedhead, which can be interesting.
But getting a novel plant is just the beginning. Once you have the plant, you have to make a few hundred or a couple thousand to spread around for growers to introduce. “One of the interesting things with geums and other plants is that they are becoming available as unrooted cuttings, usually from Costa Rica,” Horvath says. These are basically cuttings from the newly bred plants he (or other breeders) send to growers in Costa Rica and also Guatemala and Mexico. “I send the new genetics or the newly developed variety to them. What they do then is grow a lot of plant material that can meet demand continually throughout the entire year or growing season due to their perfect climate.” He points out that this is a popular form of propagation now. It allows a lot of people to grow the plant without having to have a stock plant to maintain.
“The sales for geum are snowballing today,” he says. “Every year it just seems there is a little more interest and more sales. We now have a grower on the East Coast who will grow and sell 500 of five varieties this spring.”
The next phase of Brent’s geum breeding will be to develop plants that rebloom as well as new color shifts. “I haven’t gotten too far on the reblooming geums, but I do have a few that rebloom sporadically in the fall. One hasn’t been introduced yet, but ‘Limoncello’ reblooms in a clear yellow color. ‘Sea Breeze’ reblooms as well and has 2-inch flowers that are a deep orange with folded wavy petals.”
Brent notes that geums have a lot going for them. “They bloom for four weeks, typically starting at the end of April going through May and sometimes into June. The cooler the weather, the longer they last and the more they bloom. We also noticed that when you have a mass of geums, finches come to eat the seeds.” Geums are also round and mound-like, which is a nice size and shape for most gardens.
Some of the geum companion plants that Brent recommends are Salvia x sylvestris ‘May Night’, low-growing hardy geraniums – Geranium sanguinium ‘St. Therese’ is an Intrinsic introduction – early blooming veronicas and the Jacob’s ladder Polemonium x ‘Heaven Scent’ (which Brent also bred).
“Geums are early blooming and very hardy,” he explains. “They do like rich, moist soil, but they don’t require it. Average soil will do. And they like full sun. The foliage is semi-evergreen and will make a low, green mound. Plant them closely, 1 foot on center. They do most of their growing after they bloom in June, and that would be the best time to fertilize them.”
There is a place in every garden for these new, intoxicating geums.
The genus Geum contains about 50 species of herbaceous perennials that come from temperate regions of Europe, Asia, North and South America, South Africa and New Zealand.
Many geum hybrids are hardy in Zones 4 to 9. These plants do their growing during the cool times of the year, so they can be planted in early spring or early fall. The plants prefer a moist to well-drained soil in full sun. The foliage is semi-evergreen. Blooming time will be extended if flowers are deadheaded.
Geums will begin to flower less after a few years; at this time, lift and divide them in the spring. Insects and diseases that may affect geums include downy mildew, fungal leaf spot, powdery mildew, spider mites and root weevils.