Position full sun Soil fertile well-drained soil Rate of growth average Flowering period June to October Hardiness hardy annual Lovely pure white flowers form in big flat-topped clusters which resemble lace-cap hydrangeas. They appear throughout the summer above the fine fern-like foliage. This gorgeous hardy annual has an extremely long flowering period and will often flower until the first frosts. Particularly good in wilder gardens Garden care For early summer flowers sow the seeds shallowly in seed trays in autumn and overwinter in a cold frame. Spring sowings will produce smaller plants that will flower well into autumn. Thin out when large enough to handle and potting on or planting out after the worst of the frosts have passed.