Question

Why is salvia as petaloid

Answer 1

The floral leaves (a) are only slightly reduced in this form from typical leaves.  In many broadleaf sages, they are often reduced in size.  Further, they can develop progressively into bracts by taking on some of their features like vein patterns and shape.  For an example of this, see the image of S. wagneriana.  The petiole (leaf stem) is not shown on this image.The calyx (c) is the cup-like structure that holds the flower (d, corolla) and ovary, connected to the floral stem by a stalk (b, the pedicel).  In some sages, the calyx becomes swollen (accrescent) after the flower drops, most frequently if the ovary has been successfully fertilized. Abscission is the process of the deliberate separation of a part of a plant like a flower, fruit, or old leaf from the plant.  On most sages, non-fertile calyxes fall off in a few days after the flowers.  When calyxes persist and are brightly colored, they add significantly to the floral display.  Examples are S. splendens, S. mexicana,  and S. regla.There is often a ring of hairs (annulus) towards the mouth that holds in the ripening seed.  Immature calyxes often have the mouth flattened shut, and calyxes with ripening seed (e) often open up as they dry and brown up. Actually, seeds in the mint family are really achenes, or one-seeded fruit.  They are also referred to as nutlets.