Geranium Pratense Laura - Thompson & morgan. Long lasting, weather resistant, double white flowers are produced from June onwards on upright, downy stems. The serrated leaves quickly create a mound of fresh green foliage that makes excellent groundcover for a cottage garden or perennial border. Unlike its single flowered relations, Geranium pratense 'Laura' does not self seed, making it easier to control. Height and spread: 60cm (24”).