Hardy annuals can be sown direct outside, where they are to flower. These do best on ‘poor’ soil, so don’t enrich it with fertiliser. Half-hardy annuals such as dahlias and cleome, and perennials are best sown under glass at this time of year.
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Finally, if you’re interested in growing your own food discover which vegetable seeds can be sown in March.
Here are just some of the flowers that you can start to sow in March.
Hardy annuals can be sown directly where they are to flower; prepare the ground well first, by clearing it of weeds and raking it to a fine tilth. Do not enrich the soil. Try Ammi majus, borage, clarkia, cornflowers, and Papaver commutatum ‘Ladybird’ (pictured).
Sweet peas can be sown under cover from October to March. They like a long root run, so sow into deep pots or modules. Find out how to grow sweet peas.
Annual flower mixes can be sown in March. As with hardy annuals, prepare the soil well by removing weeds and raking to a fine tilth, but do not enrich the soil.
Half hardy annuals
Dahlias are tender perennials that will flower in their first year if sown in the greenhouse in March. In autumn, dig up the tuber to store over winter, or lift and store in cold areas. Find out how to grow dahlias from seed.
Early spring is the ideal time to sow quick-growing perennials under glass. Try sowing echinacea, coreopsis, lupin or achillea and you may be rewarded with flowers this year. Find out how to grow quick-growing perennials from seed.