For three weeks of every year, in early to mid-may Clematis Montana is in its element. This climber is really no more than a one trick pony, but what a trick. The flowers, which come in many colours and sizes, from dainty pale pink (mine) to huge, super vulgar striped jobs the size of dinner plates, are pretty and plentiful and look spectacular for a very short time, after which the plant is a jumbly mess, creeping into pipework, onto roofs and strangling any nearby furniture and plants. My advice is enjoy the blooms and once they are spent be ruthless and give it a severe haircut. Next year’s flowers will grow on this year’s wood, so cut immediately after flowering and tie in and tidy up. This will allow other surrounding plants to shine when their time comes and prevent 9 months of untidy muddle.