For fabulous summer colour that keeps on going well into autumn, it’s hard to beat summer annuals. Easy to grow from seed and flowering for months, they’re fantastic value for money and great for filling gaps in borders. Here are four of our favourite summer annuals to sow now:
- Spanish flag
- Morning Glory
1. Spanish flag
Spanish flag (Mina lobata) is a vibrantly colourful annual climber that flowers abundantly in summer. The name comes from the sprays of flowers which change from bright red through warm orange and yellow, finally turning white. This fast-growing twining climber will quickly cover a trellis or obelisk, growing up to 1.8m (6ft) tall.
Sow the seeds indoors in individual pots filled with multipurpose compost and place the pots somewhere warm and bright. Soaking the seeds overnight before sowing improves germination, as does covering the pots with clear plastic bags. Plant out after the last frosts.
Cosmos (Cosmos bipinnatus) is a very popular annual that keeps on flowering for months in summer and goes on well into autumn if regularly deadheaded. The daisy-like pink, red or white blooms are a magnet for pollinators and make beautiful cut flowers.
Sow indoors in seed trays filled with seed compost and place in a propagator at 18-25°C, or cover with a clear plastic bag and place on a sunny windowsill to germinate. Once the seedlings are large enough, prick out and transplant into individual small pots. Grow on and plant out once the frosts are over.
Nasturtiums (Tropaeolum majus) can be sown indoors in spring for earlier flowers in summer, or sown directly outdoors in late spring. With their fabulously colourful flowers smothering low mounds of rounded foliage, they look sensational edging borders and vegetable beds, or spilling from containers.
Soak the seeds in water overnight, then sow them 1.5cm deep in small pots filled with multipurpose compost and leave on a sunny windowsill to germinate. Plant out after the last frosts. You can also sow nasturtiums directly outdoors in late spring.
4. Morning Glory
Morning Glory (Ipomoea tricolor) is a twining climber with heart-shaped leaves and beautiful trumpet-shaped flowers in summer. New flowers open in the morning and each one usually lasts just one day, but the plant will keep on flowering all through summer and into early autumn. Vigorous and fast-growing, Morning Glory is perfect for covering a fence or training up a tall obelisk.
Soak the seeds overnight, then sow 6mm deep in individual pots of moist seed compost and place in a propagator or on a sunny windowsill to germinate. Insert thin canes into the pots as supports for the plants to climb up. Harden off and plant out in late spring or early summer.