More than a decade ago, Frank Strickland daubed the pollen from 'Gold Medal' onto the stamens of 'Brandy', two justly popular hybrid tea roses. No fireworks were reported, and it was only one of many similar crosses he made that year and like other crosses made in other years. Late that fall, he sowed the resulting seeds, and by the next spring he had his first look at some never-before-seen flowers.
Meanwhile, the biggest rose nurseries in the world -- Jackson & Perkins, Weeks Roses and Conard-Pyle -- were doing the same thing. The difference was the numbers. Where Strickland sowed 1,000 seeds, the big guys sowed several hundred thousand.
Beyond its unlikely origins, 'St. Patrick' -- one of four roses winning the All-America Rose Selection award for 1996 -- is mostly unusual for its color and its ability to thrive in heat. Chartreuse buds open to reveal a large (five-inch) yellow-gold flower suffused with a mint green. The actual amount of green varies with the prevailing temperature: Generally, the flowers show more green the warmer it gets.
If you grow 'St. Patrick', you'll also notice that its flower petals are unusually thick, a rare quality in roses in general and especially rare in yellow roses. Thick petals mean the flower is more tolerant of wind, rain, sunlight and heat, and that it makes a long-lasting cut flower. It is also why 'St. Patrick' excels in hot regions -- Florida, Texas and Arizona, for example -- where other roses wither and fail.
The plant itself is unusual, too. It is tall, to five or more feet, and its leaves are a unique gray-green. 'St. Patrick' is a vigorous-growing hybrid tea, meaning it tends to produce large, well-formed single flowers on long stems. Its disease resistance is very good. The past president of the New England Rose Society, Ann Hooper, reports that in her Boston garden, "I was too busy to fuss over my roses last season, and 'St. Patrick' was the most disease-free of them all. It had no black spot and no powdery mildew, two diseases that appeared on other roses in my garden."
The process of making a hybrid rose is simple enough. In a nutshell, take pollen from the stamens of one rose and apply it to the stigmas of another rose. Once fertilization occurs, the flower fades and the rose "hip" swells with the maturing seeds inside. Sow the seeds from inside the hips and see what you get.
Before you begin, commit to good recordkeeping and labeling of every plant and offspring every step of the way. If one of your crosses is truly special, the world will want to know how it came to be.
To choose which roses to cross, look for desirable characteristics, such as color, fragrance or plant growth. These choices are in large measure the "art" of rose hybridizing. If you'd like a disease-resistant rose, for example, it helps to know that hybrid parents such as 'Brandy' and 'Sexy Rexy' are known to pass along this trait.
If the flower was not fertilized, the bud will shortly dry up and fall off the plant. If it was successful, the hip will stay green and begin to swell. It will be mature and ready to harvest some three to four months later.
Harvest the mature hips in late October and store them in the refrigerator in a plastic bag with a moistened paper towel for one month. After Thanksgiving, sow the seeds in a shallow flat or seed tray filled with fine sand. Plant seeds 1/2-inch deep, and maintain the flat in darkness at 55° to 60°F. Germination should begin in four to six weeks and continue for several weeks. Only 20 to 25 percent of the seeds germinate. Once they do, keep flats under fluorescent lights for 16 hours a day. Transplant to individual growing pots once the seed leaves straighten and become green.
You'll see the first bloom about four months after sowing seeds. The first flowers are smaller than would come from a mature plant, but all the important features -- color, form, fragrance and substance -- will be the same. Of a typical 1,000 seeds Strickland sows, some 250 grow. He selects the best 25 to 50 after seeing the flowers, and by the following spring he's down to the best two or three seedlings.
For more information. You can learn more about creating your own rose hybrids as a member of the Rose Hybridizers Association. Visit their Web site www.rosehybridizers.org/.
Michael MacCaskey is former editorial director of National Gardening.
Photography by Suzanne DeJohn/National Gardening Association
Article published on June 23, 2008.