Plants

Sesamum — genus of sesame plants Sesamum Sesamum is a small genus of flowering plants in the family Pedaliaceae, best known for S. indicum (sesame). Species produce oil-rich seeds used as food, oil, and in traditional pra…

Shallot: a mild, cluster-growing onion (Allium cepa variety) Shallot Shallot, a mild-flavored member of the onion family (Allium cepa), is grown as clustered bulbs and prized in cooking for its delicate sweet-onion and garlic-like notes.

Shamrock: symbol, botany, and cultural significance Shamrock Young sprigs of three-leaf plants long associated with Ireland, the shamrock is a botanical term, cultural emblem and seasonal tradition with botanical, historical and symbolic dim…

Shonan Gold — a Japanese yellow citrus cultivar Shonan Gold Shonan Gold is a Japanese citrus hybrid developed in Kanagawa Prefecture, prized for its bright yellow rind, sweet juice, easy peeling and use as a specialty table fruit.

Plant shoots: definition, structure, development and uses Shoot A shoot is the above-ground new growth of a plant — stems with their leaves, buds and flowers. This article explains shoot structure, development from seed, seasonal growth, uses a…

Shrub: definition, characteristics, uses and distinctions Shrub A shrub (or bush) is a woody, multi-stemmed perennial plant. This article summarizes form, variation, ecology, cultivation, pruning, propagation and how shrubs differ from trees an…

Silk tree (Albizia julibrissin) — description, history, uses, and ecology Silk tree Albizia julibrissin, the silk tree or mimosa, is an ornamental Asian tree with feathery bipinnate leaves and pink powder‑puff flowers. Overview of identification, range, cultivatio…

Silphium: the lost seasoning and resin of ancient Cyrene Silphium Silphium was a prized plant and resin in the ancient Mediterranean, especially Cyrene; its exact identity is uncertain and it may be extinct. This article outlines its uses, histor…

Silver birch (Betula pendula) Silver birch Betula pendula, the silver birch, is a slender deciduous tree native to Europe and parts of Asia; valued for its white bark, catkins, rapid colonising habit and uses from ornament…

Sirdavidia (monotypic genus in the Annonaceae family) Sirdavidia Sirdavidia is a monotypic genus of tropical flowering plants in the Annonaceae, known from Gabon. Its sole species, Sirdavidia solannona, is rare, bee-attracting, and named in hono…

Snowdrop (Galanthus): description, cultivation, and cultural significance Snowdrop Snowdrops (Galanthus) are small bulbous plants that bloom in late winter or early spring. Known for their white, drooping flowers, they have horticultural, ecological and cultural…

Sod (turf): composition, cultivation, uses, and history Sod Sod is living grass and the soil bound by its roots, harvested as rolled or pieced turf for instant lawns, erosion control, sports surfaces and landscaping. This article covers com…

Solanales: the nightshade and morning-glory order of flowering plants Solanales Solanales is an order of flowering plants within the asterid clade. It includes familiar food and ornamental species (nightshades, morning-glories) and is characterized by sympetal…

Sophora — genus of pea-family trees and shrubs Sophora Sophora is a genus of about 45 species of small trees and shrubs in the pea family (Fabaceae), known for pea-like flowers, hard-coated seeds, and uses in horticulture, medicine and…

Sophora davidii — deciduous Chinese shrub with blue-and-white pea flowers Sophora davidii Sophora davidii is a deciduous legume shrub from southwestern China, noted for its blue-and-white pea flowers, compact habit to about 3 m, and occasional use in ornamental planting…

Sophora koreensis Sophora koreensis is a legume species native to Korea, known for its uncertain taxonomy and limited distribution. It is considered uncommon or threatened and has drawn attention fr…

Sophora macnabiana A species of the pea family (Fabaceae) native to central Chile and Gough Island, grown as an ornamental for its showy flowers, multiple leaflets and pods; sometimes confused with N…

Sophoreae: a tribe of the legume family (Fabaceae) Sophoreae Sophoreae is a historically defined tribe of Fabaceae (legumes) noted for relatively simple flowers, pinnate leaves, and quinolizidine alkaloids; modern studies show it is polyphyl…

Sorghum: a climate‑resilient grain and forage grass Sorghum Overview of sorghum, a genus of drought‑tolerant grasses used for grain, forage, syrup and biofuel; distribution, traits, history, uses and agronomic importance.

Sorrel (Rumex acetosa): culinary herb and garden perennial Sorrel Sorrel is a perennial leafy herb (Rumex acetosa) known for its tart, lemony flavor. Used in salads, soups and sauces, it grows easily in temperate gardens and appears in many regio…

Soursop (Annona muricata): description, uses, cultivation, and safety Soursop Soursop (Annona muricata) is a tropical fruit with spiky green skin and white pulp. Native to the Americas, it is eaten fresh or processed; it has culinary uses and traditional med…

Soybean (Glycine max) — overview, uses and cultivation Soybean Soybean, an annual legume domesticated in East Asia, is grown worldwide for its protein- and oil-rich seeds used as food, feed and industrial raw material.

Spelt (Triticum spelta): an overview of the ancient hulled wheat Spelt Spelt is an ancient hexaploid hulled wheat cultivated since prehistoric times. This article covers its taxonomy, history, cultivation, processing, culinary uses, nutrition and heal…

Sphagnum (peat moss): biology, ecology, and human uses Sphagnum Sphagnum is a group of mosses important for peat bogs and water regulation. This article describes their biology, ecological role, uses, and conservation issues in temperate wetlan…

Spinach (Spinacia oleracea) Spinach Spinach is a versatile leafy green valued for its vitamins, minerals and culinary uses. Native to Asia, it is eaten raw or cooked and appears in many cuisines and cultural referenc…

Spiraeoideae — historical subfamily in the rose family (Rosaceae) Spiraeoideae Spiraeoideae is a historical name for a Rosaceae subfamily. Once applied to shrubs with dry fruits, it was merged into a broader Amygdaloideae that now includes many fleshy-fruited…

Spruce (Picea): characteristics, ecology, and uses Spruce Spruce are coniferous evergreen trees of the genus Picea found across northern temperate and boreal regions. This article covers identification, species, ecology, uses, and distinc…

Square Foot Gardening: A Compact Method for Productive Vegetable Beds Square foot gardening Square foot gardening arranges small, intensively planted beds in 4×4-foot modules to maximize yield, reduce work, and conserve resources. Ideal for beginners, urban plots, and rai…

Squash (plant): types, origin, uses, and botanical classification Squash (plant) Squash (genus Cucurbita) are New World plants in the gourd family grown worldwide for food, seed and ornament. This article summarizes their botany, major types, cultivation and cu…

Stamen: structure, development, and role in flowering plants Stamen The stamen is the pollen-producing male organ of a flower. This article explains its parts, development, role in pollination and fertilization, common variations, and biological si…

Star apple (Chrysophyllum cainito) Star apple A tropical fruit tree in the Sapotaceae family, known for round sweet fruit with a star-shaped seed pattern; valued fresh and in desserts across the Caribbean, Central America and…

Stigma (botany): structure, function and variation in flowering plants Stigma (botany) The stigma is the pollen-receptive tip of a flower's pistil. This article outlines its structure, types, role in pollination and fertilization, variations across species, and its i…

Urtica dioica (stinging nettle): identification, ecology, uses and safety Stinging nettle Comprehensive guide to Urtica dioica (stinging nettle): how to identify it, where it grows, its ecological role, traditional and culinary uses, and safety plus first aid for stings…

Stolon (botany): horizontal stems and vegetative propagation Stolon A stolon is a horizontal stem that spreads from a plant and forms new individuals. This article explains form, function, differences from rhizomes, examples, ecological roles, and…

Stomata: Structure, Function, and Role in Plant Physiology Stomata Microscopic pores on plant surfaces that control gas exchange and water loss. Covers stomatal structure, mechanics, diversity, evolution, and significance for plants and ecosystems…

Drupe (stone fruit): botanical structure, common varieties, and culinary uses Stone fruit Drupe (stone fruit) explained: botanical structure of exocarp, mesocarp and endocarp, common varieties from peaches and cherries to mangoes and coconuts, plus culinary uses from fr…

Straw: composition, history, uses, and distinctions Straw Straw is the dry stalks of cereal plants left after harvesting grain. This article explains what straw is, how it differs from hay, its historical and modern uses, processing, and…

Strawberry (Fragaria × ananassa): description, history, and uses Strawberry An overview of the cultivated strawberry, its botanical features, origin as a hybrid, cultivation, culinary uses and notable distinctions. Explains why the strawberry is not a true…

Styphnolobium japonicum — Japanese pagoda tree Styphnolobium japonicum Deciduous ornamental legume native to East Asia, grown for fragrant white flowers and shade; formerly placed in Sophora and used in traditional medicine for flavonoids like rutin.

Subalpine zone The subalpine zone is the high-elevation belt below the treeline characterized by cold-adapted trees, krummholz, meadows and shrubs; it varies worldwide in species, structure, and…

Subshrub: low, partially woody perennial plants (suffrutex) Subshrub Subshrubs (suffrutices) are low-growing perennials with a woody base and softer stems. This article explains their traits, examples, horticultural uses, and how they differ from sh…

Succulent plant: adaptations, diversity, and uses Succulent plant Succulents are plants adapted to survive dry conditions by storing water in leaves, stems, or roots. This article explains their characteristics, evolution, common groups, uses, an…

Sugar beet (cultivated Beta vulgaris): overview, cultivation and uses Sugar beet A temperate root crop grown for its sucrose-rich taproot. Covers botanical traits, cultivation and processing, history, global production and byproducts such as pulp and molasses.

Sugarcane: biology, cultivation, uses and global production Sugarcane Sugarcane (genus Saccharum) is a tropical grass grown for sucrose-rich stalks. This article describes its biology, history, cultivation, processing, uses and environmental and econ…

Sumac: overview, characteristics, uses, and identification Sumac Sumac refers to several shrubs and small trees known for pinnate leaves, clusters of red drupes called sumac bobs, small five-petaled flowers, and varied uses from spice to dye. Di…

Sunflower (Helianthus annuus): biology, cultivation, uses and history Sunflower Sunflower (Helianthus annuus) is an annual Asteraceae plant known for its composite flower head, seed and oil production, ornamental varieties, pollinator value, and use in agricul…

Suriname cherry (Eugenia uniflora): pitanga, Brazilian or Cayenne cherry Suriname cherry Eugenia uniflora, commonly called Suriname cherry or pitanga, is a small fruiting tree in the Myrtaceae family, native to coastal South America and grown worldwide for ornament and…

Swainsona formosa (Sturt's Desert Pea) Swainsona formosa A striking Australian native, Swainsona formosa—commonly called Sturt's Desert Pea—is an emblematic arid-zone pea known for its glossy red flowers with a dark central 'boss' and cu…