Even the amateur hybridizer should have some knowledge of what characteristics improve the quality of the iris flower. This knowledge should assist the amateur in determining what to aim for and how to best evaluate the resulting seedlings.
The first that usually comes to mind is color. The object is to produce clean, clear, and smooth colors. There should be no muddy tones dulling the flower’s color clarity.
Closely related to color, light colors look frosty or waxy and dark colors look velvety or satiny.
This determines the durability of the flower to maintain its form for three days or longer while at the same time withstanding environmental elements. Poor substance is one of the most difficult traits to breed out; therefore, it is important to consider breeding only those flowers with good substance.
Strong sunlight causes many colors to fade or burn. Many spot very badly in the rain, particularly those with velvety falls. Selective breeding of fading flowers with unfading flowers to produce offspring with good unfading characteristics.
Standards must be sufficiently strong to not open too far or to be prone to collapse. Falls should have flare; the angle of the falls determines the shape of the fall. Falls should have wide hafts with a pleasing round form. Broad falls and hafts gives the flower the appearance of being twice as large as those lacking these characteristics. Breeding should avoid the following fall faults: (1) reflexed falls: falls slightly fold in toward the stem and have a slight outward curve at the tip; (2) recurved falls: falls completely turn in toward the stem and have an abrupt curve near the tip; (3) incurved falls: drooping falls that begin flared but the tips turn inward instead of out; (4) tucked falls: bend immediately after the beard toward the stem.
This trait is recessive, so the parent may or may not pass it to the offspring. However, it may occur with only one parent possessing fragrance; however, it is more likely to occur when both parents possess fragrance. Many irises are odorless. Other iris have many fragrance types: sweet, spicy, scents of sweet peas, orange blossoms, lilacs, violets, grape juice, pineapple, and cloves.
Lace occurs at the edges of the petals. This trait is incompletely recessive since there will occasionally be non-lacy offspring from crossing two lacy parents, and occasionally non-lacy parents will produce lacy offspring.
Two large parents will result in larger offspring than a cross with one large parent and a smaller parent.
This trait must be taken into consideration with the size of the flower. Tall, thin stalks do not belong with large flowers.
Ideal branching results in a strong stem in proportion to the height and size of the flower with a minimum of three, and preferably four or five, well-spaced branches with a sufficiently wide angle to present the flowers individually and devoid of crushing the flower against the stem.
Flower size and height of stalk must be proportional to each other.
Longer Blooming Season
Irises with more branching and three or more buds per branch will provide a longer bloom time.
Hardiness and Vigor
Select parents that are hardy and bloom well with fast increases and intercross them or cross with another that is even stronger.