Hybridizing -- Aitken Style
Terry Aitken of Vancouver, Washington
Our interest in irises began almost twenty years ago as green thumb, first time homeowners. We planted many types of plants, but were almost immediately impressed with the wide range of colors and patterns available in TB irises. We began collecting these variants, and the large commercial color catalogs simply encouraged this quest. We began with ten plants, then twenty, then more. This year's first-bloom plants will number nearly 10,000 seedlings and 250 newly introduced varieties from other growers. This is in addition to the established 1200 named varieties and field rows of several thousand reselect seedlings, all of which occupy about three acres.
When you consider that these three acres of plants have the capability of increasing in quantity to occupy four times that space the following year, it is obvious that a high sense of selective-discipline is absolutely essential to one's survival!
Poor quality plants are pulled and thrown while still in bloom; average quality plants go on a 'hit list' to be thrown as time permits. Only 'superior' plants are returned to the fields as transplanting begins September 1st. By mid-November, transplanting is essentially complete, and we can look down the rows of labels with satisfaction and look forward to an even more spectacular bloom season next year.
Our "theory" in iris breeding has everything to do with the word "quality". What sense of selection occurs that determines which plants stay and which go? Quality is a relative value. Plants we would save ten years ago, we would not hesitate to throw today. Quality changes with time. We can sense annually subtle improvements over the year, or generation, before. Quality is the sum of the evaluation of all the characteristics of a plant. Color intensity is taking on an almost fluorescent brilliance. Petal substance has become as hard and brittle as cabbage leaves. Stems with four or five branches are common and triple sockets a pleasant bonus. Vigor can be observed in the off bloom season with the size of clumps and a count of the spent bloom stalks. Some plants show superior resistance to leaf spot; some are resistant to rot. Some flowers are more resistant to late spring freezes than others. Some flowers even return to bloom again in July and August, not to mention September, October and November! (Yes, we have joined the race to produce quality everblooming irises!)
Some five years after I had begun "collecting" irises, I decided to try my luck at hybridizing. I was extremely fortunate to be living in a haven of world class hybridizers. Early talks and tours of seedling patches with Gus Schreiner, Bennett Jones and George Shoop set the stage with role models and able coaches. As our horizons expanded, hybridizers throughout the northwest became our "benevolent family" by choice. Over fifteen years, our communications have spread nearly world-wide, as we find that gardeners (and hybridizers in particular) share a common enthusiasm in their quest for quality new plants.
An iris hybridizer is an iris judge, officially or otherwise, as plant evaluation and reselection are the over-riding prerequisites to this activity. Partly it is taught through the AIS Judges manual, but largely it is an inherent skill or aptitude which a person must have. Experience and training simply sharpen one's skills and expand one's perspective of a given subject.
ADVICE TO BEGINNING HYBRIDIZERS
1) Early on, I often heard that you need to hybridize for approximately 10 years before introducing your first plant. After six years of hybridizing I introduced my first irises in 1983 -- Cascadian Skies (TB), Hellcat (IB) and Lemon Rings (SDB). I would suggest that the beginner could save a whole lot of time, toil and frustration by simply restricting their hybridizing efforts to using the absolute top quality, newer plants available. These are usually the AM award winners, which have grown well throughout the Continent.
2) Another rule of thumb was "one introduction per thousand seedlings". Again, the use of awarded parents can reduce this ratio to one in three hundred - maybe!
3) More advice -- "Veteran iris buyers will not buy your irises until they have seen and personally evaluated your plants." It is essential that the beginning hybridizers get their prospective introductions to national and regional tour gardens. From then on, the plant will establish your reputation for you - either good, bad or indifferent. It is extremely difficult to live down a poor introduction. YOU (your skills) will be judged, by others, on the basis of the quality of plants you select for introduction.
4) "Your reputation will be substantially enhanced by winning AIS awards." First, you must have a good iris, then people have to see it. Distribution to conventions is essential. Limit your introductions to just a few in each class to avoid competing against yourself (splitting votes).
5) "Linebreeding creates weaknesses". We frequently hear that plants look great in the originator's garden, but perform poorly in different climates or soils. Because of this, we have specifically developed a system of breeding irises together that originate from different geographic areas of the country (NW X SW) or (NE X NW), etc. This formula increases the likelihood that your plants will thrive under a variety of climatic conditions (and increases the likelihood of winning awards).
Our best breeders? Lace Artistry (pollen only) is producing a very high percentage of reselect seedlings. Its biggest weakness seems to be bud count (usually 7) - need to breed it with high bud count pod parents, like Paradise. Orbiter and Gyro crossed with Spartan and Warrior King are producing wonderful forms in fuschia blends. Vivien is producing the best red bearded blues. We are using Laced Cotton to produce "speckle plics". These are flowers with lace texture where the plicata band breaks down into spots or speckles. (The fourth generation of these will bloom this year). For IB's, any of the forementioned TB's should work well. Everyone in the Northwest is getting sensational IB's from Marmalade Skies. For BB's, Pixie, Rain Dance, and Chubby Cheeks seem to guarantee exceptional results. Among the Japanese irises, Knight in Armor is producing many fine seedlings, as is Cascade Crest. Among the rebloomers, we are down the road four generations (and seeing rapid progress) with Seawolf, Stellar Lights, Sapphire Hills, Victoria Falls and Immortality. During July and August, this past year we had two introduction quality seedlings show up; a fine white out of ((Seawolf x I Do) X Immortality), and a fine blue from the line listed above. Seawolf showed up four times in that parentage! We are also working with other early rebloomers - Champagne Elegance (pollen fertile), Eternal Bliss (very pod fertile), Maiden (unknown), Many Happy Returns and Point Made (pod fertile). The first everblooming irises are just a generation or two away!
Hybridizing is a fascinating activity. There are infinite possibilities and endless surprises along the way. A hybridizer is a long shot gambler. Every cross should be made with the intention of winning the Dykes Medal. A hybridizer is an opportunist. Many surprises occur in the seeding patch, and the breeder needs to realize that these may be winners, even if not the intended objective. No iris is an end product by itself. It simply represents one step up the ladder to infinity, and provides the opportunity for further options and higher standards of quality. There will always be room for new hybridizers willing to work towards these objectives.
(Reprinted from Region 7 "Irisarian" Newsletter, 1990- 1991)