Growing annuals from seed is simple and, with warmer months here, now is the time to sow
a guide to growing beautiful summer-flowering annuals
Raised from seed to flower in a single season, annuals are one of the most satisfying plant groups to grow. ‘You could almost devote an entire cutting patch to hardy and half-hardy annuals,’ says rachel siegfried of green and gorgeous, who grows cut flowers on her farm in england. ‘They are the most productive of plants because the more you cut them, the more they flower. They’re also very easy and, because they grow quickly from seed into a large plant, they are less susceptible to pests and diseases. so there’s always a good success rate with them.’
In october and november, it is the hardy annuals that take centre stage. rachel advocates doing a first sowing in late summer, no later than the first or second week of February. she sows most seeds into modular trays to be started off in a green house or protected area, but for tiny seeds she sprinkles them on the surface of seed compost in trays. These are then grown on and will be big enough to plant out in the garden in March. ‘If you get them into the ground in March they put down their roots and really get going,’ explains rachel. ‘They may not look like they’re doing much above ground over winter, but as soon as it warms up in spring, they will shoot away and produce plants that flower earlier and are often almost twice the size of others sown in spring.’
rachel will then make further sowings in March or april, so that she has a succession of blooms. ‘The one drawback with hardy annuals is that they don’t flower for a very long period – maybe only two to four weeks,’ she explains. ‘successional sowing is important, so you can stretch out the flowering period.’
If you do not have a greenhouse or a protected space, some annuals such as poppies and cornflowers can be sown directly into the ground, either in late summer or as soon as the soil has warmed up in spring. ‘Wait until you see the first flush of annual weeds greening up the soil in spring, because then you know that it’s warm enough for seeds to start germinating,’ advises rachel. sowing seeds outside is more of a lottery, as they have to compete with slugs, snails and the weather, but if it works, it can save time. sow the seeds in drills and thin out the seedlings as they grow, with final spacings of 30 to 50cm. Most annuals need an open, sunny spot in well-drained soil to thrive, as well as some sort of shelter. Taller plants such as cornflowers and ammi will need supporting in some way. rachel uses pea netting strung between posts, which she puts in when the plants are still young so they can grow up and through the netting.
FOCUS ON: SWEET PEAS
sweet peas are part of the hardy annual group and are rachel’s best-selling flower. she grows both the spencer hybrids and the more highly scented grandiflora types, such as ‘Juliet’ and ‘erewhon’.
rachel sows her sweet peas in the first week of March. ‘sweet peas are earlysummer flowerers, and starting them off in the autumn, as they would in nature, means that you get bigger, stronger plants.’ she sows the seed into root trainers. They give the length that the roots need and are designed to open outwards when you are ready to plant, so the plug plants can be extracted easily. ‘I don’t soak or chit the seed first: I just put them straight into seed compost and water them in well.’
Ideally they need a bit of heat to get them germinating, otherwise they will sit there and rot in cold, wet compost. so bring them inside and put them on a warm windowsill before taking them outside to a sheltered and covered area as soon as the shoots appear. ‘It is important to do this otherwise the plant will get too leggy,’ she says. ‘don’t mollycoddle your plants.’ The other way to produce good, sturdy plants is to pinch out the growing tips at three to four leaves, which encourages side shoots and results in a strong, multistemmed plant.
rachel keeps her plants in the root trainers all winter in a greenhouse and then begins to harden them off in august by bringing them outside. They will eventually be planted out at the end of september, beginning of october, at the base of a pea netting support. ‘sweet peas like cool, moist roots with their heads in the sun, so we tend to mulch around the base of the plant to keep the moisture in,’ says rachel. Keep the seedlings well watered and watch them shoot up. Before you know it, you will be harvesting heavenly sweet peas – but remember to keep picking every day or at least to deadhead, otherwise the plant will fade prematurely. Seeds and seedlings n are available from 8 seedsforafrica. co.za and 8 ballstraathof.co.za, as well as nurseries countrywide
The Oxfordshire cutting garden at flower farm green and gorgeous