Plants

Grapevine (Vitis spp.): biology, cultivation and uses Grapevine Grapevines (Vitis spp.) are woody climbing plants grown for grapes used in wine, fresh fruit, raisins and other products. This article summarizes their biology, cultivation, propag…

Grass: definition, biology, uses, and distinctions Grass An accessible overview of grasses (Poaceae and similar plants): their form, classification, ecology, uses, and how they differ from sedges, rushes and other grass-like plants.

Gravitropism: how organisms sense and grow in response to gravity Gravitropism Gravitropism is the directed growth or movement of plants, fungi, and other organisms in response to gravity. It explains why roots grow down and shoots grow up and describes the c…

Green bean (Phaseolus vulgaris): overview, uses, and cultivation Green bean The green bean is the edible immature pod of Phaseolus vulgaris. This article describes varieties, culinary uses, nutrition and safety including lectins, and basic cultivation, sto…

Green Manure: Soil-Building Cover Crops and Their Uses Green manure Green manure are crops grown to enrich soil organic matter and nutrients by being incorporated into the soil; they reduce erosion, suppress weeds, support pollinators and improve s…

Green roof (living roof) Green roof A green roof is a building roof partially or completely covered with vegetation and growing medium, offering stormwater control, insulation, habitat and urban cooling while requiri…

Grevillea — Australian genus of flowering shrubs and trees Grevillea Grevillea is a diverse genus of about 360 evergreen flowering plants in the Proteaceae, native to Australia and nearby islands; valued for ornament, nectar for birds, and a few tim…

Groundskeeper A groundskeeper maintains outdoor spaces—parks, sports fields, campuses and estates—managing turf, plants, irrigation, pest control and seasonal work to ensure safety, functionalit…

Guanacaste (Enterolobium cyclocarpum): description, range, uses Guanacaste Guanacaste (Enterolobium cyclocarpum) is a large leguminous tree of tropical Americas, noted for ear-shaped seed pods, expansive canopy, agroforestry uses, and status as Costa Rica…

Guarana (Paullinia cupana): botanical profile, uses, and cultural significance Guarana Guarana (Paullinia cupana) is a South American climber whose caffeine-rich seeds are used as stimulants, traditional tonics, beverage ingredients and supplements; it has notable in…

Guava (Psidium) — tropical fruit, plant characteristics, and uses Guava Guava refers to tropical plants of the genus Psidium and their edible fruits. This article covers their botany, native range, varieties, cultivation, nutritional value and common u…

Gum arabic (acacia gum): origin, composition, uses, and production Gum arabic Gum arabic is a natural exudate from Acacia species used as an emulsifier, binder and stabilizer in food, pharmaceuticals, inks and art. This article covers its sources, chemistry,…

Gymnocalycium: the globular South American cacti Gymnocalycium Gymnocalycium is a genus of small, globular cacti from South America, valued for their ribbed stems and showy flowers. Widely cultivated, some species are used as grafted colourful…

Gymnosperms — seed plants with exposed ("naked") seeds Gymnosperm Gymnosperms are non-flowering seed plants whose seeds develop exposed on scales or stalks. This article summarizes their groups, structure, fossil history, ecological roles and dif…

Gynoecium: the female reproductive organ of flowering plants Gynoecium The gynoecium is the collective term for the female reproductive structures of a flower, composed of one or more carpels that bear stigma, style and ovary, and that give rise to se…

Habanero chili (Capsicum chinense) Habanero chili A small, intensely hot chili of the species Capsicum chinense, known for fruity flavor, multiple ripe colors, and widespread use in Caribbean and Mexican cuisines.

Haptophyte (Prymnesiophyta): single-celled algae with a haptonema Haptophyte Haptophytes are mostly unicellular, chiefly marine algae distinguished by two flagella and a haptonema. They include coccolithophores important to the carbon cycle and have a rich…

Hardiness zone (plant hardiness and growing zones) Hardiness zone A hardiness zone groups locations by average minimum winter temperatures to indicate which plants can survive there. It is a planning guide, not a guarantee, and complements local…

Hardwood (wood from angiosperm trees) Hardwood Hardwood is timber from flowering (angiosperm) trees, typically deciduous or broad-leaved evergreen. Its structure, density and uses vary by species; common uses include furniture,…

Harvest: collecting crops and other cultivated resources Harvest Harvest is the process of gathering mature crops or other cultivated resources. This article covers methods, timing, machinery, causes and consequences of crop failure, and non-pla…

Hawthorn (Crataegus): description, ecology, uses, and identification Hawthorn Hawthorn (Crataegus) is a genus of thorny shrubs and small trees in the rose family, common across temperate Europe, Asia and North America. Known for spring flowers, small apple-l…

Hay: dried forage for animal feed, storage, and common uses Hay Hay is grass and other plants cut, dried, and stored as feed and bedding. This article explains types, production, storage, uses, quality factors, and how hay differs from straw an…

Hazel (Corylus): description, species, uses and ecology Hazel Hazel refers to shrubs and small trees in the genus Corylus (family Betulaceae), valued for edible hazelnuts, wood and wildlife habitat across the temperate Northern Hemisphere.

Hedge (hedgerow): definition, structure, history and ecological role Hedge A hedge or hedgerow is a deliberately planted line of shrubs and trees forming a boundary, shelterbelt or wildlife corridor. It has agricultural, cultural and ecological significan…

Heliantheae — the sunflower tribe (Asteraceae) Heliantheae Heliantheae is a large tribe of the sunflower family (Asteraceae), with about 190 genera and 2,500 species, primarily native to the Americas and including the cultivated sunflower…

Helichrysum: the everlasting flowers of the daisy family Helichrysum Helichrysum is a diverse genus of about 600 species in the family Asteraceae, known for papery, long-lasting flower heads and uses in ornamentals, dried arrangements, traditional r…

Heliconia — tropical flowering plants (lobster-claws, false bird-of-paradise) Heliconia Heliconia is a genus of colorful tropical plants known for showy bracts. Native to the Americas and Pacific islands, they are valued in gardens and floristry and play specialized r…

Hellebore: winter-flowering perennials of the genus Helleborus Hellebore Hellebores (Helleborus) are hardy, often evergreen perennials valued for late-winter and early-spring blooms. This article covers their appearance, cultivation, history, uses, and…

Hemp: cultivation, uses, history, and distinguishing features Hemp Hemp is the non-intoxicating form of Cannabis cultivated for its fibers, seeds, and versatile industrial uses. This article reviews its biology, cultivation, history, products, and…

Henna: plant, dye and the art of temporary body decoration Henna Henna (Lawsonia inermis) is a plant-derived dye used for body art, hair coloring and textiles across South Asia, North Africa and the Middle East. This article covers its propertie…

Henry C. Andrews — English botanical artist, publisher and botanist (fl. 1794–1830) Henry Charles Andrews British botanical artist, engraver and publisher active c.1794–1830, known for hand-coloured engraved plant plates and The Botanist's Repository. His middle initial long misreporte…

Herb: definition, characteristics, cultivation, uses and history Herb Overview of herbs: botanical traits, life cycles, common examples, cultivation and harvesting, culinary and medicinal uses, safety and historical context for gardeners and readers.

Herbaceous plant: non-woody flowering plants — traits, life cycle, and uses Herbaceous plant An accessible overview of herbaceous (non-woody) plants: form and anatomy, annual/biennial/perennial life cycles, ecological roles, common examples and differences from woody plant…

Herbal (book): history, contents, uses and legacy Herbal A herbal is a book describing plants, their identification and practical uses. This overview covers typical contents, historical development from antiquity to the early modern peri…

Herbarium (botanical collection of preserved plant specimens) Herbarium A herbarium is a curated collection of preserved plant specimens and associated data used by botanists for identification, research, conservation and education.

Herbicide: types, mechanisms, history, uses and environmental effects Herbicide A herbicide is a chemical used to control or eliminate unwanted plants. This article explains types, how they work, historical development, common uses, and environmental and safet…

Hermann Müller and Hermann Muller: notable people sharing the name Hermann Muller Disambiguation and concise biographies of three notable figures named Hermann Müller/Muller: a 19th‑century German botanist, H. J. Muller the American geneticist, and Hermann Mülle…

Hesperis matronalis (Dame's Rocket): description, habitat, and identification Hesperis matronalis Dame's Rocket (Hesperis matronalis) is a fragrant mustard-family plant, often grown ornamentally and naturalized in parts of North America; blooms in late spring and favors roadsid…

Hesperocallis — the desert lily: description, habitat and taxonomy Hesperocallis Hesperocallis is a monotypic genus whose single species, Hesperocallis undulata (desert lily), occurs in North American deserts. The genus has a complex taxonomic history and close…

Heteropogon contortus — black speargrass (tanglehead) Heteropogon contortus Heteropogon contortus is a perennial tufted grass of the Poaceae family, native to tropical and subtropical regions. Notable for its twisted awns, fire tolerance, and traditional u…

Hibiscus (rosemallow): overview, description, uses and cultural significance Hibiscus Hibiscus is a diverse genus of flowering plants known for large, colorful blossoms. Widely grown in tropical and temperate gardens, some species are used ornamentally, culinarily,…

Hibiscus syriacus (Rose of Sharon): description, history, cultivation Hibiscus syriacus Hibiscus syriacus, commonly called Rose of Sharon, is a hardy flowering shrub in the mallow family, prized for late-summer blooms, cultural symbolism and use as an ornamental hedge…

Hibiscus trionum — bladder hibiscus, flower-of-an-hour Hibiscus trionum Hibiscus trionum is an annual species in the mallow family, native to the eastern Mediterranean. It has pale petals with a dark centre and an inflated calyx; cultivated as an ornam…

Hickory: characteristics, species, ecology and human uses Hickory Hickory (Carya) are deciduous trees valued for pinnate leaves, hard wood and edible nuts. This article covers identification, major species, reproduction, uses, cultivation and con…

Hoja santa (Piper auritum) — the sacred leaf of Mexican cuisine Hoja santa Hoja santa (Piper auritum) is a large aromatic perennial in the pepper family, native to Mexico and Central America, used as a culinary wrapper, flavoring herb, and in traditional…

Holly (Ilex): description, ecology, uses and cultural significance Holly Holly (genus Ilex) comprises evergreen and deciduous shrubs and trees with glossy leaves and bright berries. Valued ornamentally and in winter traditions; some species are used to…

Honeyberry (Lonicera caerulea): blue honeysuckle, haskap Honeyberry Honeyberry or blue honeysuckle (haskap) is a cold-hardy shrub grown for elongated blue edible berries, valued for their tangy flavor, antioxidants and ease of cultivation in northe…

Honeycrisp (apple cultivar) Honeycrisp Honeycrisp is a popular apple cultivar developed at the University of Minnesota, known for its crisp texture, sweet-tart flavor, long storage life and strong commercial demand.