Crazy for daisies

With nearly 25,000 species, daisies make up one of the largest plant families. But their pretty flower heads are not quite what they seem. What looks like one flower is in fact a cluster of lots—sometimes thousands—of tiny flowers in the center, with a ring of what looks like petals but is in fact more flowers around the edge.

The striped ray florets surround a center of tiny disk florets.

Orange pom-poms are made of individual flowers and colorful hairs.

Pink petals surround a spiny conelike center that is full of nectar.

Tubular flowers are produced by this critically endangered Hawaiian plant.

Yellow-tipped red florets, which look like flames, give this plant the name “firewheel.”

The round flower head is made up of small flowers, ranging from purple to metallic-blue.

The spiky globe

thistle is also called the blue hedgehog.

Three separate florets look like a single flower.

Daisies such as the treasure flower, the common daisy, and chicory have large outer petal-like ray florets, surrounding the disk florets in the center. Each disk floret is in fact five fused petals that form a tubelike flower, which you can see clearly in the whorl flower. The sunflower has a large head so you can make out the individual disk florets as they bloom, from the outside in. Each floret produces one seed. The flower-packed heads of daisies make them much more attractive to insects and makes pollination a lot easier. Most have bright colors to attract insect pollinators, such as bees, but the tropical Mutisia flower is pollinated by birds. The other tropical daisies, stifftia and the Maui island-aster, are unusual because they grow on trees.

The largest sunflower head ever grown was in 1983, at 321⁄4 in (82 cm) across.

Each petal-like ray floret is a lopsided flower.

The orange ray florets attract bird pollinators.

Yellow disk florets at the center produce pollen and make seeds.

Edible blue flowers, which are bitter in taste, can be eaten in salads.

The purple florets fade to cream toward the center of the flower head.