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Flower seeds to sow in March

Flower seeds to sow in March

Growing flowers from seed is a fantastic way to fill your garden with colour at minimal costs. Now that spring has arrived, there are plenty of flower seeds to sow both indoors and directly outside to give you beds filled with blooms this summer. We’ve put together our top tips on sowing seeds and suggestions on planting the best seeds in March.

Tips on sowing seeds

  • If it’s been a very cold, wet spring, wait until the weather improves to sow outdoors, or start your seeds off indoors. As a rule of thumb, if the weeds are starting to grow, it’s probably warm enough to sow hardy annuals outside.
  • Before sowing seeds outdoors, it’s important to prepare the ground. Dig over the soil, remove weeds and stones and rake the surface to produce a fine, crumbly texture ready for sowing.
  • Getting the watering right is one of the most important aspects of growing plants from seed. Seeds sown outdoors need regular watering in dry periods. For seeds sown indoors, keep the compost moist, but remember that seeds don’t enjoy sitting in sodden compost.

Seeds to sow indoors in March

Many half-hardy and tender plants can be sown indoors now and will give you a fantastic display of colour in summer. Here are some seeds to sow indoors in March:

  • Half-hardy annuals like cosmos, cleome, antirrhinum (snapdragons), French marigolds and calendula (pot marigolds).
  • Dahlia mixes - many are available as seeds and can be sown indoors now, giving a fabulous display in summer for very little cost.
  • Climbing annuals like Thunbergia alata (Black-eyed Susan), Ipomoea lobata (Spanish Flag) and Ipomoea purpurea (Morning Glory) – these can be planted out as soon as the frosts are over and will quickly cover an obelisk, arch or pergola with their colourful flowers.
  • In cold areas, sow sweet peas indoors in root trainers – toilet roll inner tubes work well, giving the long roots space to develop.

Seeds to sow outdoors in March

As the weather improves and the soil warms up towards the end of the month, many hardy plants can be sown directly outdoors. Here are a few to try:

  • Hardy annuals, including Californian poppies, cornflowers, Nigella (love-in-a-mist) and sunflowers. March is also an excellent time to sow annual wildflower mixes.
  • You can sow sweet peas directly outdoors this month in mild areas, provided there’s no risk of frost.
  • Nasturtiums are a great addition to any kitchen garden and can be sown outdoors from late March.
  • If the weather is good, try sowing some night-scented stocks (Matthiola bicornis) in a sunny spot near a seating area to enjoy the delicious fragrance on long summer evenings.

We have everything you need to start sowing, including pots, seed trays, compost and a fantastic range of seeds. Visit us today and get your flower garden started!