I used to think that a flower blooms once the petals open up, but since a sunflower is a composite flower, the process is a bit different.

To refresh your memory: composite flowers are made up of the ray and disc flowers. The ray flower is made up of the outer petals – what we ordinarily consider regular petals – and the disc flowers are the cluster of flowers in the middle of the flower – generally speaking, of course.

And, yes, to my great enlightenment, there are disc flowers on sunflowers! I’d never thought about it, nor really looked up the nitty-gritty about sunflowers. As you should know, my normal modus operandi is to get seeds, plant them and have my happy surprises along the way. So I did indeed enjoy watching the sunflowers bloom.

The ray petals open on one side first, and the disc flowers start opening along the outer rim. You can see how the disc buds are forming from the outside to inside. Undeveloped buds are still black.

The ray flower is fully open (and attacked by insects unknown) and the disc flowers continue opening in a tightening spiral. I also love that pattern of overlapping spirals in the middle!

Finally, all the disc flowers have bloomed and the centre of the flower protrudes like a pincushion. Now I have to wait while the seeds ripen in the head before I can harvest them.

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