Sap The juice of a plant contained in the cells and vascular tissue.

Sapling A young tree; a seedling or any young tree before the wood hardens.

Scandent Ascending or loosely climbing. (See also Climber.)

Scarification 1) Abrasion or chemical treatment of a seed coat in order to speed up water intake and induce germination. 2) Removing moss and thatch from a lawn using a scarifier or rake.

Scion A shoot or bud cut from one plant to graft onto a rootstock (stock) of another.

Scree A slope comprising rock fragments formed by the weathering of rock faces: simulated in gardens as scree beds, in which high-altitude alpines that need excellent drainage may be grown.

Seed The ripened, fertilised mule containing a dormant embryo capable of developing into an adult plant.

Seedhead Any fruit that contains ripe seeds.

Seedling A young plant that has developed from a seed.

Selection A plant selected for particular characteristics and usually propagated to retain the same characteristics.

Self seed To shed fertile seeds that produce seedlings around the parent plant.

Self-fertile Of a plant that produces viable seed when fertilised with its own pollen.

Self-pollination The transfer of pollen from the anthers to the stigma of the same flower, or alternatively to another flower on the same plant (see Cross pollination).

Self-sterile A plant unable to produce viable seed after self-fertilisation, and requiring a different pollinator in order for fertilisation to occur. Also known as “self-incompatible” — incapable of self-fertilisation.

Semi-deciduous See Deciduous.

Semi-determinate Used of tall or cordon tomatoes that will only grow to 1 to 1.2m (3 to 4ft) long.

Semi-evergreen See Evergreen.

Sepal The outer whorl of a flower, usually small and green but sometimes coloured and petal-like.

Set 1) A small onion, shallot bulb, or potato tuber, selected for planting; 2) A term describing flowers that have been successfully fertilised and have produced small fruits.

Sexual reproduction A form of reproduction involving fertilisation, giving rise to seed or spores.

Sheet mulch A mulch using artificially produced material (e.g. plastic).

Shoot A branch, stem or twig.

Shrub A woody-stemmed plant, usually branched from or near the base lacking a single trunk.

Sideshoot A stem that arises from the side of a main shoot.

Simple (mainly of leaves) Undivided.

Single digging A method of digging in which only the topsoil is turned over to a depth of one spit. (See also Double Digging.)

Snag A short stub or frayed end left after incorrect pruning.

Soil mark The usually noticeable point on a plant’s stem that shows the original soil level before the plant was lifted.

Species A category in plant classification, the lowest principal rank below genus containing closely related very similar individuals.

Specimen plant A striking plant, usually a tree or shrub in prime condition, grown where it can be clearly.

Spent (of flowers) Dying or dead.

Sphagnum mosses Mosses commonto bogs; their moisture-retentive nature is valued when used as a component of growing media, for example in orchid cultivation.

Spike A racemose and hence indeterminate inflorescence that bears unstalked flowers along a common axis (stem).

Spikelet A small spike, forming part of a compound inflorescence; often applied to grasses where the flowerhead consists of several flower, with basal bracts.

Spit The depth of a spade’s blade, usually 25-30cm (10-12in).

Spoon-type Applied to the florets of chrysanthemums (and some other flowers) in which the quill-like florets expand to form a spoon shape at the tips.

Sporangium A body that forms spores on a fern.

Spore The minute reproductive structure of flowerless plants, such as ferns, fungi and mosses.

Spray A group of flowers or flowerheads on a single, branching stem, such as occurs on many chrysanthemums and carnations.

Spur 1) A hollow projection from a petal, often producing nectar. 2) A short branch or branchlet bearing flower buds, as on fruit trees.

Stalk A general term describing the stem of a leaf or flower (e.g. petiole, peduncle).

Stamen The male reproductive organ in a plant, comprising the pollen-producing anther and usually its supporting filament or stalk.

Standard 1) A tree with at least 2m (6ft) of stem below the first branches (see also Half-standard). 2) A shrub trained so that it has a clear length of stem below the branches (1-1.2m/3-4ft for roses). 3) One of the three inner and often erect perianth segments of the iris flower. 4) The largest, usually uppermost petal of a flower in the subfamily Papilionoideae (peas and beans of the family Leguminosae).

Station sow To sow seed individually or in small groups at fixed intervals along a row or drill.

Stem The main axis of a plant, usually above ground and supporting leaves, flowers and fruits.

Sterile 1) Not producing flowers or viable seed. 2) Of flowers without functional anthers and pistils.

Stigma The apical portion of a carpel, usually borne at the tip of a style, which receives pollen prior to fertilisation.

Stock plant A plant used to obtain propagating material, whether seed or vegetative material.

Stolon A horizontally spreading or arching stem, usually above ground, which roots at its tip to produce a new plant. Often confused with runner.

Stone fruits Fruits, also known as “drupes”, with one or more seeds (“stones”) surrounded by fleshy, usually edible tissue. They are common in the genus Prunus (e.g. apricots, plums, cherries) and some other plants, such as mangoes that produce indehiscent woody fruits.

Stool A number of shoots arising, more or less uniformly, from the base of an individual plant, for example some shrubs cut back regularly to produce propagating material and also chrysanthemums.

Stooling The routine pruning back of woody plants by coppicing.

Stopping See Pinching out.

Strain A loose undefined term sometimes applied to races of seed-raised plants, not a term accepted under the International Code for the Nomenclature of Cultivated Plants because of its imprecise definition.

Stratification Storage of seed in warm or cold conditions to overcome dormancy and aid germination.

Stylar column A column of joined styles.

Style The usually elongated part of a carpel between the ovary and stigma, not always present.

Subfamily A category in plant classification, a division within the family.

Sub-lateral A sideshoot originating from a lateral shoot or branch.

Subshrub 1) A low-growing plant that is entirely woody. 2) A plant that is woody at the base but has soft, usually herbaceous growth above.

Subsoil The layers of soil beneath the topsoil; these are usually less fertile and of poorer texture and structure than the topsoil.

Subspecies A subdivision of a species, higher in rank than varietas (see variety) or forma.

Succulent (of plants) A plant with thick, fleshy leaves and/or stems adapted to store water. All cacti are succulents.

Sucker 1) A shoot that arises below ground from a plant’s roots or underground stem. 2) On grafted plants, a sucker is any shoot that arises below the graft union.

Sympodial Definite growth of a shoot terminating in an inflorescence or dying; growth is continued by lateral buds.

Systemic Term describing a pesticide or fungicide that is absorbed and distributed through a plant when applied to the soil or foliage.