weightlifting and rugby

Question
say if you start weightlifting at 15 do you stop growing in heights?and what is and overlap?cheers

Answer
My opinion is  this:

No weights until at least 18 or 19 to allow for the bones to grow fully. Weight training too early can harden the growth platelets at the ends of your bones, it may not stunt height or growth but may cause repeated injury to occur.

Rather than weights go with "own body weight" exercises:

rope / wall climbing
press ups (1 arm, two arm) very very slow.
lunges
squats (no weights)
pull ups (wide, narrow, over hand, underhand)
wrestling with a similar size opposition
dips
Sprint training
stair climbing

If you do decide to go to weights only get your routine from a fully qualified instructor who is not a rookie. Ask for a resume, references, testimonies and interview 3 or 4 before picking one.

Without your asking they should be making you do strength tests etc to see where you are now before starting.

If a trainer neglects to ask about any injuries, weaknesses, goals then do not train with them.