Helenium 39double trouble39 is a tall hardy perennial which produces excellent cut flowers this contemporary variety is the first fully double helen39s flower33 with charmingly pretty narrow yellow petals fashioning a ruff around the centre helenium 39double trouble39 blooms from july to october it39s great for producing gorgeous colour to wildlife areas and cottage garden borders in late summer it is of course a favourite of butterflies and bees height 80cm 4