BBC Gardeners' World

Scree

1) The dry, rocky detritus found at the base of mountains.

2) A mixture of stones and sharp sand, which, when mixed with soil, forms a growing medium for alpines and other plants requiring good drainage.

Seed

The fertilised and matured ovule of a plant. It contains the embryo of a new plant, as well as nutrients for its development.

Seedling

A young plant cultivated from seed (not from a cutting).

Self-coloured

A term used largely in floristry to describe blooms entirely of a single colour, ie, with no variegation, veining or shading.

Self-fertile

A plant having the ability to pollinate its own flowers.

Self-sterile

A plant that's unable to produce fruit without the pollen of another. A plant that cannot be fertilised by its own pollen.

Sepal

The leaf-like outer segment at the base of a flower that resembles a petal. A division of the clayx that's usually green, but may be coloured.

Serrated

Refers to leaves whose margins are saw-toothed.

Serrulate

Refers to leaves whose margins are minutely saw-toothed.

Sessile

Having no stalk. Flowers having no stem and appearing directly from the base. Leaves having no petioles.