Rhododendrons: Moving large rhodos - advice needed!

My bro-in-law is giving us 4 large rhododendrons (ranging from 5-6' high, 4-5' wide) which are being rescued from a building site. Any advice anyone can give me about giving them the best chance for survival would be greatly appreciated.

This is what I know so far -- tell me if I'm on the right track: I will use transplant fertilizer when planting them, and try to keep them from drying out (that will be hard this summer!). I have lots of rhodos & azaleas on my property, and they seem to be doing pretty well so I'm sure I have the soil they like. They have not bloomed yet, and look like they are in excellent health.

Anything else I should/shouldn't be doing?

Thank you all!

Cheers,
Lulu in Langley, BC

 

tie up the plants branches and such with stout rope to avoid digging damage, water the plant thoroughly prior to digging (a few days before and then the night before), dig it in cool weather, dig a wide shallow root ball about 1/3 the size of the dripline, use a sharp spade to cut the roots, wrap the rootball in burlap and tie with a strong biodegradeable string, gently move the plant from one location to the nesxt, plant at the same depth as it was growing, water thoroughly through the next 6 months or hire someone to do all that for you. I am not a big fan of transplanting solutions, they contain IBA which I have heard is suspect of not having any effect at all on rooting of plants. Clean, sharp tools are best to use and I would suggest you try adding bonemeal to the new hole prior to planting to supply nice, organic phosphorous for the roots - if you are concerned about angry bovine issues you can use fishbone meal.

 

Thanks for the advice, Paul. They seem to be doing well and are blooming!

Cheers,
Lulu in Langley, BC