Convincing OGRs to bloom in southern USA

I have been searching this forum for an answer to my question and i cant seem to find a great answer. I bought some old garden roses back when i was in utah and brought them with me to south carolina. I have apothecary rose, tuscany superb, nuits de young, and capitaine john ingram. At the time i purchased them i was pretty ignorant about rose varieties and didnt know i would be moving to the south. I soon learned that gallicas really dont like it here. So my plan was to try and cross these roses with some native ones near where i live to try and improve the health while still letting me play around with them. These roses have been in my yard for 3 growing seasons and none have produced flowers. My guess is that it may be too warm to induce the dormancy that they want. Does anybody have any tricks to get them to flower? I really want to work with them if i can. Im wondering if it also has to do with the way i prune them, or if i need to give them more fertilizer in the spring. Ive been doing the leave 2/3rds rule with pruning. Im thinking i may just forgo pruning this year and see what happens. I really hope it isnt one of those cases where they will never be productive. Thanks for your advice in advance.

1 Like

“Chill hours” of “cold” appear to be negated by heat hours. My only suggestion would be to ice them as you have to French hybrid Lilacs in warmer climates. You refrigerate tulips and other similar bulbs for the same reason. Some plants require periods of cold to induce flowering. I WANTED Charles de Mills. After watching it eat the entire yard for years with NO flowers, I decided to treat it like a tulip or harsh season Lilac and freeze it with ice dumps several times over the winter. It worked.

If you’ve ever noticed, bare root once-flowering OGRs usually flower as soon as they break dormancy after planting, even in warm climates. They may never flower again, but they certainly do that first year. They’re stored in cold storage until shipped, so to them, they’ve had “winter”. If you’re able, retain some milk or other beverage containers you can freeze larger blocks of ice in to be placed around the plants you want to flower. Pack them in ice as often as your energy and desire permit. You won’t hurt them and you MAY obtain some flowers from them.

If you grow more of these types, you’ll discover there are some with enough China genes in them to flower in your conditions. Cardinal de Richelieu flowered (AND ate the yard) without icing. CdM only ate the yard with NO flowers, but icing did produce blooms. Good luck!

2 Likes

What time of year are you pruning?

Mark

Ive been pruning either the middle of summer or fall since i read to prune after they flower and i figured that because i have a longer growing season that it was the best way to do it. If i am doing it wrong, let me know! I would love to be doing everything better.

It may not make a significant difference, but failing other methods, you could also try growing those roses in pots that you lift out of the ground for the winter, allowing their root zone to be exposed to as much cold as your climate’s winter can provide. Placing the potted roses in the shade during winter might help to prolong the effects of any cold events that occur. Maybe if the roots are chilled to a greater degree, it will help to convince the plants that they’re in a colder climate than they actually are and help to induce dormancy. Making sure that the previous year’s leaves are removed is another step you might take if you aren’t doing that already. Of course, roses treated in that way would probably benefit from being set back into the ground for the summer to help keep their roots cooler. There is no guarantee that doing this will change the outcome in any way, but it could be worth a shot.

Stefan

2 Likes

Chill hours will still be an issue for you, but I believe you’re pruning too late. Old garden roses tend to bloom on old wood produced during the previous growing season. The ideal pruning time would be immediately after flowering. Since your roses haven’t bloomed, I realize you won’t know exactly when that is, but it would be earlier than mid summer. I would strongly suggest forgoing pruning entirely for at least this year. I live on the Mississippi Gulf Coast in zone 9a, so I have experience trying (and frequently failing) to make OGR’s bloom! There are some antique roses that are said to have China blood and be more heat tolerant. It might simply be a case of trial and error to find which varieties will bloom where you are. I bought Henri Martin for that reason a couple of years ago. Really hoping to see blooms in the spring.

Mark

He likely is pruning too late, Mark, but bare roots of those OGR types which have been pruned short for storage and shipping, then held in cold storage, still flower after planting and breaking dormancy. I have had so many budded Gallicas and other old European Garden Rose types flower their first season, then never again in my warm Zone 9b gardens.

I visited a nursery in southern Louisiana (zone 9a) with my family years ago where we bought a few once-blooming OGRs, and they were clearly doing well–one was ‘Banshee’, and another was identified as ‘Hippolyte’, although it was really some other dark purple hybrid China that I have still not managed to tie convincingly to a known cultivar. So I would agree, if you can’t manage to get the ones you have to flower, there are some others that should flourish, although I will caution that most hybrid Chinas tend to be very infertile with a few major exceptions.

When I lived in Atlanta Georgia which is a zone 7 area, every year I would go out around thanksgiving and Christmas and strip the leaves off the plants. The once blooming roses bloomed every year in the spring. I have also found that here in Missouri, zone 6 that if by Christmas the plant hasn’t dropped its leaves if I want flowers I have to strip them off. So if you able to remove the leaves that may help with blooming