Trimming rhodedendrons

Google confused me, so I'm turning to you with the chainsaw party coming.

One of the items needing address is a rhodie growing at the corner of my house. Is growing onto my roof, and I can't have that.

I've read that depending on the species depends on the time of year to cut.it flowers pink, that's all I know.

I don't want to kill the thing, but I also don't want the top of it growing over my roof anymore. 

Is spring safe to cut before it blooms? Should I just rip it out? Do I need to go take pictures for the right answer?

I have lots of rhodos at my house, including a big tree that is the height of my two-story house and it turns pink once a year.

I usually wait until after it blooms to do any pruning, not sure if that's correct or not but none of them have died because of it.

Generally, they're pretty hardy and can take a ton of abuse.

I'm the last person to ask about plant care.  I had a very similar situation where the whole end of the 2-story house was just Rhododendron 20' high and 40' wide.  I hacked at some of it with a chainsaw, then hooked a chain around the base of the three stumps and ripped them out.

Two years later, I have beautiful Rhododendrons that came up from the leftover roots and they're about 4' high and 2' wide.

When I try to kill things, they come back.  When I try to make something grow, it usually lasts about a month.

Long story short, they're pretty hardy.  I would think any dormant time (late summer through early spring) would be fine.  I don't think I'd do them now... likely they have already started the juices flowing.

Prune away, you won't kill them. They bloom on last year's growth though, so that's why most will prune after the blooms are done, so you don't get bare spots during bloom time. Only caveat is to make sure that the threat of frost has passed, as the pruning will encourage new growth which may not be hardy enough for sub freezing temps.

My mom had a large roady that my Dad cut down to about a foot off the ground. Mom was  furious. It came back and had more blooms in the following years. I think they are pretty hardy.

I've cut them down to a stump and they come back. Might take a few seasons to create a nice bush again. But sometimes they just get too big and unruly to trim properly and maintain a nice shape. They're very strong shrubs.

This is all great to hear. Maybe I Wil take it back to stump form for a few season and try to get it under control again.

In a similar vein, is there something I can put on limbs or stumps to prevent them growing back? I remember my dad had some sticky black stuff in a yellow plastic jar you painted on the cutoff to prevent regrowth, but I have no idea what it was anymore. 

In reply to RevRico :

Years ago my father used to use that gooey, sticky, black sealer used on roofs and foundations. Can't think of the name of it, but it worked. Should be able to pick it up at HD or Lowes.

RevRico said:

 

In a similar vein, is there something I can put on limbs or stumps to prevent them growing back? I remember my dad had some sticky black stuff in a yellow plastic jar you painted on the cutoff to prevent regrowth, but I have no idea what it was anymore. 

 

Tordon RTU