we bought some laurel plants 3ft in height a couple of years ago and they are doing well and are now approximately 6ft in height. The depth of the hedge is really thick and growing wildly but the tops are hit and miss and a bit gappy in places. If we trim the sides back and they re-shoot quickly will it hinder the growth on the top at all, by putting all the strength into the new side shoots. We are trying to get the hedge at least another 2ft high to give us some privacy. we've never trimmed the top of the laurel at all so far. any advice would be appreciated.