If I want to create a compact, recurrent blooming Polyantha-liked rose with small to medium, single to semi-double flowers in very large clusters and glossy, healthy leaves, is American Pillar worth to use? I really like its large clusters of single, relatively large bicolored flowers, and its the only hybrid setigera available to me. As I observed, AP is very vigorous, performs well even in shady areas, no blackspot, set hips. It can get mildew but far less terribly than comments on HMF, better than many Hybrid Wichs (or even Knock Out in semi-shade position). What I’d like to know are: 1) Does AP carries recurrent gene (KSN-copia)? As its pollen parent is regarded as an unnamed red Hybrid Perpetual, not every HP seems to rebloom well as well as healthy. So anyone gets a recurrent blooming AP seedling or F1? 2) Does AP really very prone mildew? I plan to do dwarf Polyantha/Miniature x AP, could it totally waste of time?
It’s a fertile triploid so your possibilities could be quite interesting. I don’t have the answers to your specific questions but I would use it on Rouletii.
It might be worth a try. I would probably put ‘Rouletii’ pollen on it rather than the reverse, and then (depending on seedling yield and behavior) keep only the seedlings that are everblooming/juvenile flowering. It should carry at least one copy of a repeat-flowering allele, since Van Fleet said that its pollen parent was a remontant rose with some R. multiflora in its background. That shouldn’t correspond to any traditional hybrid perpetual, at least not according to the prevailing understanding of rose backgrounds at that time. I haven’t personally tried using ‘American Pillar’ in breeding, so I can’t say for sure what you should expect, but some repeat blooming seedlings should be possible. I have not noticed any mildew on it in my generally humid East Coast U.S. climate.
Stefan
Thanks. I think your suggestion makes sense. ‘Lady Gay’, the pollen parent of ‘The Fairy’, could be a triploid hybrid Wich. (I don’t think LG’s pollen parent, ‘Bardou Job’, could be a diploid anyway). In my climate TF is extremely healthy, free flowering and possess much Wich. characters. It is a very fertile diploid. Perhaps what should I do is just pollenate as many flowers as possible, and then discard seedlings without juvenile flowering.
Mingwei