FLOWER POWER
Let the sun shine in
Starting a sunflower from seed in a yoghurt pottle on a sunny classroom windowsill is an early gardening experience many of us will be familiar with.
Their speedy growth, ability to reach great heights in a short time and cheerful countenance makes sunflowers extremely gratifying to grow.
These annuals also have some serious flower power properties: after the Chernobyl disaster in 1986, scientific experiments found that sunflowers were also able to lift radioactive contamination from soil. Fields of sunflowers have also been planted at Fukushima.
When to sow
Sunflower seeds can be sown from August until January (when soil temperatures are between 10 degrees Celsius and 30C) and take between 50 and 100 days to flower. The skyscrapers obviously take longer than the littlies so should be sown in spring and early summer but you can keep sowing and planting dwarf varieties until early
January.
Growing instructions
Sunflowers like good soil as well as the next plant, but will get by in surprisingly mean conditions. They need lots of sunshine and not just for growth. Sunflowers are heliotropic, meaning their flowers follow the sun from east to west, so consider this carefully when planting.
They have long, inquisitive roots and are best sown direct; Raising them in trays then transplanting them knocks a good foot off their height. Sow seed about one knuckle deep, or buy punnets from your garden centre.
They look stunning planted en masse, another reason to sow them direct, as it saves you the tedious task of transplanting them all. Protect seedlings from snails, slugs and birds. Water them regularly but don’t feel that you need to be hypervigilant, as sunflowers are relatively drought tolerant.
Despite their friendly faces, sunflower roots have antisocial (allelopathic) tendencies that can inhibit the growth of nearby seedlings (which on the positive side means they can keep weeds down), so plant them at least 40cm away from shallow-rooted annuals.
Varieties
Dwarf, semidwarf, tall and giant forms are available. Compact, fast-to-flower varieties, which are the best varieties for pots, include ‘Big Smile’ (only 45cm tall and blooms 50 days after sowing); ‘Petite Bouquet’ (50-60cm tall, flowers in 45 days and has branching blooms in a mix of colours) and ‘Incredible Dwarf’, a pint-sized sunflower that flowers just eight to 10 weeks after sowing. For huge, sunflowers (up to 5m tall), sow golden-petalled ‘Giant King Kong’ (Mr Fothergills).
If you want something different from the traditional yellow, go for pale and interesting lemon blooms, such as ‘Lemon Sorbet’ (Trade Me), ‘Moonwalker’ (Yates) or ‘Vanilla Ice’ (Kings Seeds).
Or go for noir sophistication with brown-red ‘Evening Sun’
After the Chernobyl disaster in 1986, scientific experiments found that sunflowers were also able to lift radioactive contamination from soil.
(Kings Seeds) and ‘Moulin Rouge’ (Egmont Seeds).
On that note, the branching varieties are by far the best value, with up to 18 flowers per plant, compared to just one for the standard, single-stemmed varieties such as ‘Yellow Empress’ (Yates). That makes them better for picking, too. You also get a longer season as new buds open as the older flowers fade.
Harvesting
If you want to save seeds to resow or roast or sprout for winter salads, hang a pillowcase over the head once the petals are dry and tie it off to foil birds. The head will bend over as the seeds ripen. When mature, they’re easily harvested by flexing the head.
Unless you’re a squirrel, sunflower seeds can be difficult to remove from their hulls. Kings Seeds advises soaking the shells in brine or spiced water to soften them, then patting them dry before roasting in the oven and removing the shells.