The World of Rose Breeding
The process of rose breeding is long, complicated, expensive and fascinating. While there are many rose breeders throughout the world, David Austin, is probably the most widely recognized, as the premier garden rose breeder. The following is an excerpt from an interview with Michael Marriott of David Austin Roses, published in Fine Gardening Magazine.
"The process begins by deciding which “crosses” to make. A cross is what two roses are you going to breed together to hopefully create a new rose combining the best and/or desired, characteristics from it’s parents. It’s parents being the two roses that were “crossed” with each other.
This is done in the same way Mother Nature herself does it. By collecting pollen from one rose and distributing it onto a different rose. The pollen is collected from one bloom then distributed onto a flower of a different rose variety that has had the pollen removed. The rose the pollen was collected from is the “pollen parent” and the rose the pollen is put onto is called the “seed parent”. Each individual time this is done it is recorded as one “cross”.
All of this work is done by hand. The breeder has to be very precise because you don’t want to accidentally spill pollen onto an unintended bloom.
At David Austin Roses they do anywhere from 75,000 – 100,000 individual crosses per year.
Each cross is recorded and a tag is put on each “seed parent” bloom to identify which cross it is. They record the pollen parent, seed parent and date of the cross. It’s important for the breeder to know the history of the cross so they can begin to decide if a certain rose constantly adds desired characteristics like disease resistance, fragrance, petal count etc. to a cross. This record keeping gives direction and focus to the breeding program.
Over the next several months the seed parent blooms form hips, which are the bright orange “berries” often seen on roses in the fall and winter. Inside of these hips are the rose seeds that formed from the cross. When the hips are ripened they are carefully opened up, the seeds are extracted and placed into jars again with notes again tracking the pollen parent and seed parent.
Those 75,000 to 100,000 crosses yield around 450,000 rose seeds. Each seed is sown in flats to germinate again with a record of which cross it is following it. Quite often they are chilled before hand to help germination but this varies by program. The goal is to have as many germinate as possible. From 450,000 seeds some 150,000 – 200,000 seedlings emerge.
A seedling is simply a baby rose plant. The best ones quickly reveal themselves and they are noted for further observation. Most are chosen for their flower but sometimes they are chosen for characteristics like outstanding disease resistance and will be used in the breeding program in the hopes it can pass on that trait to further generations. After the first year out of the 150,000 to 200,000 seedlings, only 15,000 are chosen to continue testing .
Over the next five years or so the roses are continually evaluated as they mature and grow. Like with the seedlings the outstanding ones quickly make themselves known and are duly noted. Decisions are made which ones are candidates for release to the public and they are further tested in a “production setting” to see how easily they propagate and will they make a nice, multi caned plant to sell the public. The ideal being a Grade 1 rose and a variety being sold on a large scale must yield a high percentage of Grade 1 plants in order to be commercially viable.
Once all the testing is done and the final decisions are made the rose enters production which takes another two years or so to build up enough quantity to release to the public.
Out of the original 75,000 to 100,000 crosses, 450,000 rose seeds, 150,000-200,000 seedlings, 15,000 plants that make it past the first year, 8-9 years later 3-6 varieties from among them are released to the public!"
As you think about Valentine's Day and all the roses you will deliver to your customers, consider all that goes into producing that flower.
Below are photos showing the process of cross pollinating, labeling and harvesting seeds:
Photo Courtesy of David Austin Roses
"Nature, left to her own devices, finds it hard to produce anything that is ugly. The work of the plant breeder should always be to enhance nature, not to detract from it....we should strive to develop the rose's beauty in flower, growth and leaf."