I know the usual advice on Rhododendrons that are way too big for their location is rip them out and plant something appropriate. But I'm not planning to do that. They were big (obviously pruned to the desired size) when I bought the house almost 30 years ago. I lost control of them (by skipping pruning a couple years) and regained control after hacking it back, a few times over the years.

June 2016, right after these flowers wilted, I hacked the top third off of them. This spring I'm going to hack the front third off as well. I have a couple places elsewhere on my property (boundary between yard and woods) where I would like to start these.

These three shrubs are at the top of a slope. Low branches are lying on the ground down the slope and twist upward from way below the base of the shrubs to form much of that front third I plan to hack off. (Other parts of the front third are horizontal branches out from the main plant).

In prior years, when I pruned off the branches on the ground from purple flowered rhododendrons that look identical to these except for flower color, many of those branches had grown tiny roots. I planted and watered those and about a quarter of them survived and the best of them is starting to look like a little shrub (rather than a branch with 4 to 9 leaves) after a few years. I'm hoping to do better this time and asking what to do different.

It was too thick last year to get any kind of look at ground level in the area I want to hack off. In July, I blindly dumped an inch or two of dirt on top of branches lying on the ground. I don't know if that helped or hurt any roots that might have been starting.

How important is the time of year for this? It is a difficult task, that I'd rather do earlier in the spring when it is cooler and there are fewer insects, even though that will sacrifice the flowers that would have developed in front.

In one of the two places where I want to put these, I pre dug a big hole in the fall, because rocks and roots make digging a major project and I wanted to reduce the size of the spring project. I put a bunch of old yard waste (from a pile of that I keep) mainly partially decomposed pine needles, sticks and roots (ripped out elsewhere years ago so very dead) in the bottom of the hole, then switched to a mixture of shredded newly fallen Oak leaves and used coffee grounds. Then I threw in a bunch of worms that popped up from a different project. Sometimes that I've tried such haphazard operations, worms go back and forth between the debris and surrounding hard packed soil all winter and loosen it all up for future root growth, vs. sometimes it all just sits there.

So in the spring I will dig all that organic mess back out (which should be trivial compared to the original hard packed rocks, roots and dirt) and try to guess whether to put it back in during transplant or what to use instead. Suggestions?

In the past, I put one rhododendron branch per hole in many locations, watered them all summer, then 3/4 of them were dead the next spring. This time I'm pickier about locations. I only want these two places. I'm pretty sure I should put several branches into each large hole, so I'm watering just the two locations. Hopefully, that increases the chances of a survivor in each hole. If multiple survive, that initially just makes it look better as they go through the stage when all the original leaves fall off and each survivor grows just four new leaves that sit unchanged for a long time while roots grow. Eventually, two or more fighting in one spot seems more likely to just work itself out rather than be a problem. Comments?