Most of us agree that flowers excite the keenest pleasure because of their beauty. Yet, to the hybridizer, these most ornamental features of most plants have their outward beauty, but many snores.
To the hybridizer, flowers are the means toward plant improvement and quality control standards in generation after generation of any established variety of decorative flowers or vegetables.
The fundamental function of flowers in pollination and seed production was revealed not so many generations ago. Learning it was one of the most helpful aids to seed merchants in pursuing excellence in garden seeds.
Nowadays, gardeners can choose a wide variety of flowers and vegetables. Each type behaves true to catalog descriptions in garden rows.
It wasn’t quite so in the olden days, not until seed merchants learned in good detail about the natural and controllable method of pollination typical of each plant.
This specialized knowledge about each kind of seed-propagated flower and vegetable has become part of the lore of flower and vegetable seed breeding.
Virtually second nature to seed merchants, it may prove equally attractive to many gardeners who wish to know something of the seed merchant’s methods of furnishing seeds for better and better flower and food gardens.
Hybridizers And Flowers
To the hybridizer, flowers are admired not for their beauty but because they are primarily the essential reproductive structures of kinds grown from seeds.
Plants differ in their flowers’ simplicity or complexity, pollination, and seed development. Some kinds, such as peas and beans, petunias and tomatoes, bear flowers and seeds in one season.
Others, like beets and cabbage, delphiniums, and other biennials and perennials, may not bloom until the second year unless one knows how to induce earlier blossoming.
Kinds Of Flowers
Kinds of flowers differ in their makeup for pollination and seed production.
Sweet peas, garden peas, and lettuce contain the means toward pollination and seed set within each flower, safeguarded naturally against unwanted cross-pollination by bee-borne or wind-borne pollen.
Seed fields of related varieties of such plants may be grown near one another, separated only enough to prevent mechanical mixing during harvesting.
Insect Pollinated Kinds
Among the decorative plants, cabbage, turnips, and related species have pollen-bearing structures and seed-yielding structures within each flower, but the flowers are open to cross-pollination by bees.
Bees are necessary for pollination (and therefore seed production) in a field of any purely bred variety of these plants.
With these kinds of flowers, seed merchants have had to learn how to use the services of bees without risking unwanted crossing between related but distinct varieties.
For instance, an ordinary cabbage and a savoy cabbage might cross, or a combination of cabbage and a variety of cauliflower. This sort of mixing is to be avoided.
Incidentally, seed merchants have learned that cabbage, cauliflower, brussels sprouts, broccoli, kale, and kohlrabi are crossable fellow sub-kinds of the same cabbage species.
To seed merchants’ credit, they have developed and grown splendid varieties within these kinds while preventing crossing between them in the seed fields.
Squashes, pumpkins, gourds, melons, and cucumbers are insect-pollinated, with separate fruit-bearing and pollen-bearing flowers.
Both types are on each plant, but the pollen-bearing flowers are usually much more numerous, have slender stems, and wither away soon after yielding pollen.
Bees visit pollen-bearing and potential fruit-bearing flowers indiscriminately. Their incidental aid enables fruit setting and seed production, which would not occur otherwise.
Unwanted cross-pollination between seed fields of related but distinct varieties of these melon-type plants is avoided because seed merchants have learned that bees, whether tame or wild ones whose colonies are known, do indeed follow time traditional beelines in gathering pollen or nectar.
They travel the shortest distance between their hive and the farthest objective flowers of the trip.
Where two different but crossable crops may lie within a straight line from the hive, the intervening crop would become cross-pollinated, and the seed crop would prove unfit for sale as a true breeding variety.
However, the unwanted crossing is avoided by placing each acreage a mile apart, each of two seed fields forming one angle of a triangle, of which the bee colony is the third angle.
Bees will not make a triangular flight from and to the hive. Therefore, they do not endanger crops thus located.
Furthermore, even though any bee should visit each crop alternately, there would be no danger of unwanted crossing since a particular worker bee at the hive removes every last grain of pollen from any departing bee.
Once a haven of refuge against crossing has been established for each cabbage variety, for instance, the exact location is safe for one type of crossable species, like one petunia, one cucumber, one winter squash, one summer squash, and one cabbage or related vegetable.
Wind Pollinated Kinds
Sweet corn, beets, and spinach are species whose potential seed-bearing flower parts become pollinated by air-borne pollen; bees or other insects play little or no interest in spreading such pollen.
Crossable crops of these plants must be isolated from one another by a significant distance, preferably miles, with due regard for the direction of prevailing winds.
Researchers sometimes isolate single-choice plants for controlled self-pollination when developing new varieties of flowers or vegetables.
Such plants can be grown singly in cloth cages. When buds have developed and flowering becomes imminent, blow-fly pupae are placed in the cool earth near each plant. They emerge as blowflies and do an excellent job as pollinators of caged plants.
Sometimes flowering of biennials is hastened for seed breeding purposes. For example, cabbages ordinarily bloom in the second year.
However, select plants stored for about 60 days at 40° degrees Fahrenheit will bloom soon after planting in the greenhouse to yield seeds for spring-time planting, enabling a whole generation from seed to source within one calendar year.
Incidentally, a cabbage in bloom is an attractive plant with showy yellow four-petaled flowers on upright branches.
44659 by Gordon Morrison