Plant Doctor Archive

No seeds on sunflower

THIS year I grew a solitary tall sunflower, thinking that I would feed the seeds to my parrot and was disappointed to find that the seeds, although looking perfectly normal (big and fat), had nothing inside the husks. Why do you think this happened? The previous year my six sunflowers plants had seeds inside the husks. My friend's one sunflower was the same as mine this year. I am anxious to grow sunflower seed again next year as the pet shop ran out of New Zealand seed for a few months, and the only sunflower seed available was from Australia and heat-treated - not a good idea for an expensive bird.

IT sounds like the variety of sunflower you grew this year was a sterile hybrid. The huge flower that we call a sunflower is actually an inflorescence made up of thousands of small individual flowers combined together. Over the years plant breeders have created lots of hybrid sunflowers with improved characteristics, such as disease resistance, dwarf growth habit, stronger stems, larger petals and yellow, orange and red petals. Some are also pollen-free, so they don't cause hay fever problems or messy pollen dropping off when used in flower arrangements.

However, one of the disadvantages of being pollen free is if you grow them on their own, or if they don't get fertilised by a pollenbearing variety, they won't set viable seed. I checked with John from the Egmont Seed Company, who has a range of sunflower varieties available, and he suggests 'Giant Russian' (McGregor's brand) and 'Skyscraper' (Carnival brand) as two of the best for reliable production of large seeds which are ideal for parrots.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.