Many flowering plants produce seeds naturally with the help of the wind or living creatures such as bees, bumblebees, butterflies, moths, and others.
When man transfers the pollen from the stamen to the pistil, it is called artificial or hand pollination. The process is simple and simple. It is something anyone can do.
Recognize The Parts Of Plants
First, we must learn to recognize a flower’s stamens and pistils. The stamens, each with its anther at the top holding the pollen, often surround the pistil in the center.
Look into the blossom of a lily (Lilium) or a hemerocallis, where these organs are easily seen. They are a prominent part of each dictamnus flower.
The pollen is a dusty powder, varying in color from almost white to various shades of yellow. On some flowers, the pollen is red, brown, or orange.
Children on grandmother’s day (perhaps children still do) held buttercups under the chins of their playmates to prove that they “love butter.”
The pollen that rubbed off on their chins as much as the yellow reflection of the blossoms proved the point. If you have sniffed the delicate fragrance of a lily and gotten too close, you may have found pollen on your face.
If you’ve walked through rows of hemerocallis wet with dew and found stains on your clothing, it was probably pollen from the blossoms.
The stigma is the upper part of the pistil. It has a surface that holds the powdery pollen when it is placed there by wind, insects, or man at the opportune time. Then if fertilization takes place, seeds will be produced. Even with hand pollination, fertilization only sometimes follows.
The pollen may have lost its strength, or the stigma may not have been ready for the pollen. Or the hot sun may have burned the pollen, or rain washed it away before fertilization. Then no seeds form.
The pollen must be taken from a plant of the same species or a closely related one. Pollen from a dictamnus placed on the stigma of a hemerocallis will not produce seed.
Examining The Helen Astor
One spring day, while enjoying the graceful flowers on the Siberian irises, I stopped to look at the reddish blossoms of ‘Helen Astor’ and the rich, velvety purple blossoms of ‘Caesar’s Brother.’
“Helen should have a velvet dress,” I thought. Perhaps if the two were crossed—it would be fun to see what resulted.
Examining a blossom of ‘Helen Astor,’ I looked for the stamens and then the pistil but couldn’t find any. That was strange. Surely Siberian irises had these organs of reproduction. But there were certainly none in sight.
Turning a blossom this way, I finally saw some powdery substance on three paddle-shaped parts underneath the plant sections between the standards (the upright petals) and the falls. But where was the pistil?
Several blossoms were torn to shreds and carefully examined- there must be a pistil somewhere. It was quite frustrating to find nothing.
A search through garden books and bulletins described all kinds of irises—the tall bearded and the cunning dwarfs—the spuria or butterfly irises belonging to the beardless group, as did my favorites, the Siberian with their narrow leaves and small graceful blossoms.
All these were represented in my garden as well as ‘Dorothy K. Williamson,’ the latter because Mr. E. B. Williamson, more than 40 years ago, knew where the stamens and the stigmas of the Louisiana irises (Iris ‘Ova and I. folios, parents of Dorothy K were located.
Hand Pollination
There was much about what hybridizers, both amateurs and professionals, could and were doing with hand pollination, which increased my eagerness to try my hand—and finally, a sketch showing just where the parts were located that I had been searching for in vain. The paddle-shaped parts were the stamens containing the pollen.
It seemed ridiculous that one could observe iris blossoms for years and not note how cleverly and differently they were arranged.
Iris species vary in shape but are structurally much alike. Instead of being a single stern, the style (the stem part of the pistil) has three branches or arms, each tipped with a two-lobed crest, something like a pair of ears.
And underneath this crest was the stigmatic lip — all very strange and different from the conspicuous stamens surrounding the single pistil on the blossoms of true lilies (urns) and hemerocallis.
Finding the Stigma and Stamens
Finding the stamens and the stigma, I had no trouble following directions. The stamens were to be removed from the pollen patent (a pair of tweezers could be used), and the pollen rubbed on all three stigmas (the upper lip) of the plant one wished to pollinate.
To prevent insects from getting to the blossoms first or afterward, the blossoms to be pollinated may be covered with a paper or plastic bag the night before. Then they are bagged again after pollinating. On some plants, such as lilies or hemerocallis, removing the stamens on the seed parent is wise so that no unwanted pollen gets to the stigma.
After each blossom is pollinated, mark it with a tag to make sure which blossoms were hand pollinated. Write the name of the seed parent first and then the name of the pollen parent.
For example, if one placed `Caesar’s Brother’ pollen on the stigma of `Helen Astor,’ the tag should read Helen Astor X Caesar’s Brother. When pollen from ‘Helen Astor’ is placed on the stigma of ‘Caesar’s Brother, ‘ the tag should read Caesar’s, Brother X Helen Astor.
44659 by Olga Rolf Tiemann