I'm new here and I want to say that Sam Mcfadden did.
It is called "White Angel" Althea.
Have you consider using Hibiscus syriacus Lil' Kim which is described as a fertile polyploidy, resulting from a stem mutation on an unidentified Hibiscus syriacus. The diploid chromosome count for Hibiscus syriacus is 2N=80 and Hibiscus Lil’ Kim is clearly not a triploid 3N=120 or a tetraploid 4N=160, which means that Lil’ Kim could have a chromosome number of 6N=240 or 8N=320. Unfortunately the US Plant Patent doesn’t identify the nature of the parent plant which could be a triploid or a tetraploid.
Hibiscus plant named ‘Antong Two'
http://www.google.com/patents/USPP19547“Parentage: Naturally-occurring branch mutation of an unnamed selection of Hibiscus syriacus, not patented.”
Hibiscus rosa-sinensis are polyploidy by nature and you may have more opportunities for chromosome alignment by using Hibiscus Lil’ Kim.
In my own research, I am using two wild Hibiscus syriacus and Hibiscus Lil’ Kim to hybridize with two yellow African Hibiscus species from the Drakensberg
zone 7 region near the tip of South Africa.
Hibiscus calyphyllus (
growing this Hibiscus for 1 year, Chromosome Count 2N=80).
http://redlist.sanbi.org/species.php?species=2585-22Hibiscus pusillus (Received
seeds from a seller in Germany, Chromosome Count n/a).
http://redlist.sanbi.org/species.php?species=2585-79 Hibiscus microcarpus (Still hunting for
seeds, Chromsome Count n/a).
http://redlist.sanbi.org/species.php?species=2585-65South African Species listing: Hibiscus
http://redlist.sanbi.org/genus.php?genus=2585 I am using this
zone Map to hunt hardy Hibiscus in South Africa.
Brandt Maxwell's (bmaxwell@san.rr.com) Climate
zone Map of Africa
http://www.oocities.org/westcornersville/africazones.gifI have an overlay animation for the above
zone Map, which aligns with the South African species maps, so send me an Email if you want a copy.
Read my Wikipedia post Hibiscus calyphyllus and note the comment on chromosome counts.
Hibiscus calyphyllus
http://en.wikipedia.org/wiki/Hibiscus_calyphyllusThere may be three routes to producing a hardy yellow Hibiscus.
1. Hybridize Hibiscus syriacus with Hibiscus rosa-sinensis.
2. Hybridize Hibiscus syriacus with Hibiscus calyphyllus or H. pusillus.
3. Recover the long lost North American native Hibiscus incanus.
As I was editing this post, I discovered that Plant Delights just reintroduced Hibiscus incanus after an absence of 125 years. The only problem is that
flowers don’t look straw yellow.
Hibiscus moscheutos var. incanus (Hairy Large Flowered Perennial Mallow)
http://www.plantdelights.com/Hibiscus-moscheutos-var-incanus/productinfo/9630/Mike