Sunday, January 7, 2024

Hybrid Hibiscus of Rusanov

 This post describes the hybrid selections of herbaceous hibiscus created by Fedor Rusanov. 

Fedor Rusanov (1895 -1979) was the founder of Tashkent Botanical Garden in Uzbekistan.  He had a long and successful career as a botanist and plant breeder. Sometime around 1940s-50s he created the hybrids of hibiscus which are called by his name now. He was working with three American species, Нibiscus coccineus, Н. moscheutos, and Н. militaris. After multistep crosses he ended up with selections which are very frost hardy, vigorous and have large flowers.  These hybrids can grow to 2.5 - 3 meters (7-10 feet) in one season producing an inch or more thick stems.  However, they will go fully dormant for winter, and all above ground parts will die back. The following spring they will regrow from the roots.  The roots are very thick rhizomes similar in the structure to the vigorous peony roots. These plants need space, sun, and supplementary water in California.  They are also extremely heat tolerant and will bloom over the summer, fall, and until the frosts. 

In my childhood I used to walk through the grounds of Samarkand College of Agriculture which had them planted in masses. I perceived them as just something given, and had no idea that someone worked for years to create these hybrids. I also had one in the backyard of my grandmother. That plant produced very large red flowers.

I started growing these from seeds a few years back and had a number of seedlings with pink, white, and red flowers.  I preserved a selection with very large pink flowers which should segregate into multiple colors.  I just started a number of seeds and hope to select other colors.  I also grow multiple clones of this pink selection, as it is very easy to create new plants from the early summer shoots. They root in a couple of weeks. Below are the pictures of my pink selection.

These are very open plants and combine very well with other plantings, see image below.

I once also had a red selection, and I may have found some seeds from it and will try to germinate them. The red flowering plant is in the below images.

The utility of these hybrids for California is in their heat tolerance and ability to continue blooming when the temperature are above 100F.  However, they might have even more use in the US states with extremely cold winters. They have been shown to perform very well in various regions of Russia and Ukraine.

My plan is to propagate these accessions from seeds and cuttings and distribute through

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