My experience is that a couple more seasons of maturity firms up those spindly canes, so I just give the wavering ones support--sometimes a twiglet that fell off a tree, although I have some nice green metal stakes with a circular "head" that can hold the weak cane also. I've also had the problem with my Braveheart which from the beginning grew big, fat canes that spread out near the top to form large cluster blooms. Those were so heavy that the stout canes couldn't always stay upright, so I would have to prop them up. However, I discovered this year that I need to prune this rose more drastically than I do most of my shrub roses. I cut it back by more than half. It is now forming all that heavy cluster growth, but it is down lower on the cane and seems able to support it much better--as opposed to taller canes that suddenly became top-heavy with all that spreading candelabra kind of growth at the top. Learning the individual likes and dislikes of our different roses is part of the fun of rose gardening. Kate

Are the leaves slowly shriveling and then the plant dies? If so, then I agree with DMForcier... damping off fungus. Prevention? Let soil dry out almost completely between waterings. Sprinkle cinnamon around seedlings. Water with 1 part Hydrogen peroxide(3%) to 4 parts water every couple weeks until plants get past the critical stage of this possible affliction -- 1st 6 weeks or so after the 1st set of true leaves. Good luck and any more questions, just ask. Kevin

Thank you both! I'm going to make the rash assumption that any pruning should be done this fall when it is waking up with the cooler weather. I am already getting hot here, so we'll be heading inside before too long. I have a large south facing window for the plants to sit in during the summer. They did ok after I brought them in last year. It has ceiling fans and A/C (of course because I couldn't survive FL without it!). I just made the mistake of putting the plants in the shade, but not removing them from the heat. There is no rush. When I saw Steven's plants I thought of it again. Thanks again!

If they are dropping seeds before you pull, your pulling may be successful for the existing plant, but the dropped seeds are creating new plants.