can cystus (broom) outgrow

they do get leggy so you could give it a prune. dont cut into the old wood though.
welcome to GoY too.

If you trim the new growth by about a third it will stay bushy. Don't delay as they can get very leggy. Mine is a bit like a tree now, but it provides colour above other plants. You can take cuttings and start off a new one to replace it with in years to come.