Hibiscus: Do hardy hibiscus cross pollinate?, 1 by Michael_Ronayne

Michael_Ronayne wrote:
Ibartoo,

As Jen indicated hardy Hibiscus will cross pollinate but you have to take each cross one at a time; some crosses will work and other crosses will not. Some hardy Hibiscus are extremely pod and pollen fertile while other hardy Hibiscus are notoriously pod and/or pollen infertile. Hand pollination, with an overload of pollen, is a must to insure that the seed embryos are fertilized and to prevent accidental pollination by the wind, bees or butterflies. Also, early morning pollination increases the chances of getting the hybrids you want. For hand pollination, I use Q-tips which are immediately disposed of after a single use.

Depending on ancestry, some hardy Hibiscus cultivates are more prone to self pollination than others. If the stigma tips are close to the anther heads you have to be carful not to pick up unwanted pollen from the intended pod parent. When hardy Hibiscus blooms in the morning the five stigma tips are generally pointed away from the anther heads; during the day the five stigma tips will bend inward to make physical contact with the pollen on the anther heads. Hardy Hibiscus are genetically predisposed to encourage cross pollination but if no passing bee or butterfly volunteers, many hardy Hibiscus will do the job themselves. Based on field observations I made this summer in Cape May NJ, the small Bruchid beetle Althaeus hibisci appears to be a major Hibiscus pollinator as will as being a major Hibiscus seed predator.

Finally there are some very popular hardy Hibiscus which are notoriously pod infertile. I have a theory as to why this is occurring but I am not ready to discuss it quite yet. In such cases it may be possible to obtain seeds by surgical intervention on the hardy Hibiscus flower bud followed by massive hand pollination. The attached photograph shows the surgically exposed immature anther heads of a hardy Hibiscus in the center of a decapitated Hibiscus flower bud, which are ready for hand pollination. Believe it or not, these decapitated buds will bloom the next day with truncated petals and a normal size style and stigma assemblage. I will know more in a month and will post my findings then. And yes, for now the pods are green and growing but they can still fail.

I would highly recommend the book “Hibiscus: Hardy and Tropical Plants for the Garden” by Barbara Perry Lawton. This book has a very complete history of hardy Hibiscus breeding efforts over the last 100 years.

Mike


This message was edited Sep 12, 2010 7:48 PM