how do i care for hydrangeas without making a mess?

Most of the mess comes from pruning at the wrong time. Find out which type you have first. The big mophead and lacecap ones flower on last year's stems, so only trim them right after they finish flowering, cut them in spring and you lose the flowers. Panicle and smooth types flower on new growth and can be cut back in late winter. Otherwise they just want morning sun, some afternoon shade, a deep water when it's dry and a layer of mulch.