You should tell us where you are gardening (city, state, gardening zone) and advice will be better targeted. I have always been willing to excise chunks of my Aesculus parviflora and send them off to folks unable to procure them any other way. Probably too late in the spring this year, with bud break well underway. I wasn't part of this original thread, but had I been, I would have posted on what Bottlebrush Buckeye can do. I started off with a bunch (9? 10?) 2 gallon pots, installed in 1992 around the inside of a circular gravel drive They've grown together wonderfully, melding with the other plantings nearby. We've had some of the oldest trunks die off, but the layering and additional stems have provided a continuous surface of foliage and blooms, and propagules from the exuberant outward attempts to consume the driveway. It is also really easy to grow from the copious seed that can be set if you keep your plants reasonably moist through droughty periods in summer. September is harvest time here at the Valley. I don't think you can plant too many of these. Landscapes are built for editing - which can also translate into sharing - so if you perceive you've over-consumed, remove some or give them away. Planting too little is also easily overcome by addition - which is what I expect the original landscape design was attempting to avoid.

@Ken- one plant can indeed turn into that. Great plant, if one has the room. ==>>> yes i understand that.. and also.. sometimes arbs plant in 3s.. to get a bigger presentation ... faster ... hence the question .. the dormant pic.. sure looks like one plant ... wonder what they will do about the road it is trying to take over.. lol .. ken

i'm seeing some 18" or more away from the trunk. I may dig around them in the spring & see whether they are suckers or seedlings. if seedlings i'll move them. I plan to prune them in the next few weeks as well. anyone have any guidance in that regard. the botanical garden here have a grove of these. last year they cut them down to stumps & they are already chest high again.

@ViburnumValley central KY Bluegrass z6, thank you, I’ll have to pay closer attention to that; several of the bloom stalks were nibbled on, so it’s hard for me to compare bloom lengths. I will definitely check that out! @kitasei2, yes, they’re in very deep shade; one side of the bed gets some morning sun, but the other side hardly gets any…but they still bloom fairly well, I think, and have grown nicely. A couple of them were sad little things when first planted. I don’t fertilize, but I do water deeply, at least once a week…maybe try watering more frequently? Mine get hit by the sprinklers every other day also.