Primula Leaf Glossary

There are many terms that are used to describe Primula leaves and an understanding of what they mean is crucial to distinguishing species.

Lamina, or leaf blade, is the flat part of the leaf.
Apex is the point or tip of the lamina.
Base is the bottom of the lamina.
Veins appear as raised lines on the lamina. See Leaf Venation in Primula
Mid rib is the prominent vein which runs from the apex through the center of the lamina.
Margin is the edge of the lamina.
Petiole is the leaf stalk which attaches the leaf to the plant stem.

Each of these parts can vary in shape as shown the diagrams.

Leaf Shapes

Leaf Margins

Leaf Apex, Venation & Bases

Leaves can be petiolate (a petiole is present). Petioles can be distinct (clearly defined), indistinct (not defined) or winged (edged with a thin flange of tissue). It is important when extracting a leaf from a plant for imaging, that the petiole is intact. Remove the leaf by gently tugging downwards along the stem.


Winged petiole