Did you know that most members of the daisy family (or Compositae) have ‘composite’ flower heads? Each ‘flower’ actually consists of hundreds of tiny flowers squashed together – the inner circle containing the true flowers that contain the reproductive organs (known as the ‘disc florets’) and the outer ring of petal-like structures are actually individual flowers posing as petals (known as ‘ray florets’), these are usually sterile but occasionally you can see the tiny stamen or stigma emerging.
A sunflower is the classic example – each individual disc floret has a single ovary and after pollination, each one develops a hard seed coat with a single seed inside, which you will recognise as sunflower seeds.
The bee in the photograph to the left is busy collecting pollen from the stamens in the open ring of flowers within the sunflower head.
Behind, in the flower to the top left you can see the ring of pistils (the female floral parts)
This Zinnia flower clearly demonstrates a ring of tiny flowers opening, they usually open concentrically, one ring at a time to help avoid self fertilisation and spread the flowering period. The pink false petals (ray florets) around the outside give the appearance of a single flower. Check out the Rudbeckia in the feature image too, see if you can spot the true flowers!
Take a close look at all of your daisies! sometimes you need a magnifying glass – to see this interesting and clever trick of nature.
If you want to find out more about the fascinating world of plants, come along on our botany short course this autumn! here is a link to the course post: Botany for Gardeners
The daisy family has recently been reclassified and is now known as the Asteraceae family and consists of over 1500 genera – see how many you have in your garden!
Fascinating fasciation! Sometimes things go a little wrong when the cells divide (caused by genetic mutation or sometimes physical damage to the growing point, causing several stems to be produced fused together. This fascinating phenomenon is known as ‘Fasciation’ look at these amazing sunflower heads we found at Le Jardin Créatif! See if you can spot any fasciation in your own garden!!