Cosmos bipinnatus ‘Purity’ is an easy to grow, floriferous plant that will provide continuous colour, impact, and interest in your garden, from early summer, until the frosts arrive in autumn. This is a great choice of plant to grow to produce your own cut flowers and provide pollen and nectar for bees, butterflies, and other pollinating insects.
Cosmos bipinnatus ‘Purity’ is my favourite Cosmos. I love the beautiful, pure white flowers that Cosmos bipinnatus ‘Purity’ produces, they are so elegant and graceful, yet prolific. These flowers are perfectly complemented by the plant’s ferny foliage, which also looks good in a vase. This is an incredibly productive plant, Cosmos bipinnatus ‘Purity’ produces a continuous bounty of cut flowers, each week. You could fill your home with cut flowers from growing just a few Cosmos bipinnatus ‘Purity’ plants. For optimum flower production, it’s really important to keep deadheading; your plants will look better, they will produce more flowers, and your plants will continue flowering for longer.
Cosmos bipinnatus ‘Purity’ is a half-hardy annual. This is a tender plant that grows, flowers, and dies; all within a period of one year. If you’re growing Cosmos bipinnatus ‘Purity’, sow your Cosmos seeds on a bright window sill or in a heated propagator, during springtime – which is from March to May – in the UK. Grow your plants in a protected environment – on a windowsill, inside a conservatory, a porch, or in a cold frame, or glasshouse, where the temperatures won’t ever fall below a minimum of 7C (45F). Harden off your plants during May, by moving your plants outside during the daytime and then bringing them back inside the warmth of your home, conservatory, or glasshouse, when evening falls.
Plant your Cosmos bipinnatus ‘Purity’ plants outside, when all risk of frost has passed – in late spring to early summertime – which is from late May to mid June – in the UK.
Plant Cosmos bipinnatus ‘Purity’ in a bright, sunny position. These plants do well in any well-drained soil; they can also be grown in pots and containers, filled with peat fee compost.
Cosmos bipinnatus ‘Purity’ plants grow to around 1m (3.3ft) tall.