Some flowers are delightfully cheerful - daisies and pansies always make me smile through winter. But in summer, the "most cheerful flower'' award would have to go to sunflowers.
There is evidence of sunflowers being cultivated by American Indian tribes as early as 3000BC in what is now Arizona and New Mexico. But they were commercialised in Russia, and most of the modern breeding took place there.
Sunflowers are easy to grow.
They are best planted from seed, sown directly where they are to grow.
Seedlings will emerge within 10 to 14 days.
Expect to see flowers within eight to 12 weeks, depending on the variety you plant. For best results, choose a sunny, well-drained position with soil rich in organic matter, and make sure it is protected from the wind if growing one of the taller growing varieties.
Consider supporting the stems with stakes.
Keep the seedlings moist, and use mulch to conserve moisture and suppress weeds.
A fortnightly liquid feed will be beneficial.
Sunflowers are prone to fungal conditions so avoid watering the foliage, especially in the evenings.
If you want giant flowers, you need to make sure that each plant has plenty of room - spacing of 50cm is recommended by some experts.
If they are closer, flowers will not be as large. Giant flowers also need plenty of feeding to fuel the growth rate. Giant Russians can reach more than three metres tall, and each plant produces one huge, bright yellow flower that can measure 30cm in diameter.
Royal velvet is about 1.5m tall, and usually has one large primary flower with deep red petals followed by several smaller flowers on secondary branches.
Smaller varieties can be grown in the garden or in large pots. These grow only about 50cm tall and tend to have numerous flowers.
To grow sunflowers in pots, choose one of the dwarf varieties, and make sure the pot is at least 25cm or more in diameter.
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