Pocket BotanistReference
Plant glossary.
Definitions for the plant care, botany, and identification terms used on the Pocket Botanist site and app. Sourced from standard botanical references.
- Calcium oxalate
- A crystalline compound found in many common houseplants (Monstera deliciosa, pothos, philodendrons, peace lilies, dieffenbachias). The needle-shaped crystals cause oral irritation, drooling, and vomiting when chewed by pets or children. Listed by the ASPCA as the primary toxic principle of these plants. Monstera care guide.
- Cultivar
- A plant variety produced by selective breeding or sport selection in cultivation, with traits worth preserving (variegation, flower color, leaf shape). Named in single quotes after the species, for example Monstera deliciosa ‘Albo Variegata’. Cultivars are usually propagated vegetatively (by cuttings or division) because they do not come true from seed.
- Dormancy
- A period of slowed or paused growth, typically triggered by short days, cool temperatures, or drought. Many tropical houseplants enter a partial dormancy in winter and need less water and no fertilizer until growth resumes in spring.
- Family (botanical)
- A taxonomic rank above genus. Family names end in -aceae (Araceae, Asteraceae, Solanaceae). Plants in the same family share evolutionary ancestry and often similar care preferences. Monsteras, pothos, philodendrons, peace lilies, and ZZ plants are all in the arum family (Araceae) and share broadly similar care.
- Fenestration
- The splits and holes that develop in the leaves of certain plants, most famously Monstera deliciosa. Fenestrations appear as the plant matures and gets adequate light. Biologists have proposed that they evolved to let light through to lower leaves, reduce wind damage, and reduce surface area for heavy rain. Monstera fenestration.
- GBIF (Global Biodiversity Information Facility)
- An international research infrastructure that aggregates biodiversity data from hundreds of contributing institutions. Its backbone taxonomy is one of the standard references for plant species names. Pocket Botanist uses GBIF as a secondary reference taxonomy.
- Genus
- A taxonomic rank above species. The first half of a scientific name is the genus, capitalized, for example Monstera in Monstera deliciosa. Plants in the same genus are closely related and often hybridize.
- Hardiness zone
- A numbered geographic region indicating how cold the winters get in an average year. The USDA Plant Hardiness Zone Map uses zones 1 to 13, in 10 degree Fahrenheit bands, based on average annual minimum temperature. Used to predict whether a plant can survive outdoors year-round. USDA hardiness zone explainer.
- Interveinal chlorosis
- Yellowing of leaf tissue between the veins, while the veins themselves stay green. Usually caused by iron, manganese, or magnesium deficiency, less commonly by root damage. A diagnostic clue: whole-leaf yellowing is more often overwatering; chlorosis between veins is more often a nutrient issue. Pothos yellow leaves.
- Node
- The point on a stem where a leaf, branch, or aerial root grows out. New roots grow from nodes, which is why stem cuttings for propagation must include at least one node to root successfully. Plant propagation explainer.
- Photoperiod
- The length of light each day, which triggers flowering, dormancy, and other seasonal responses in many plants. Photoperiod is why short-day plants (poinsettias, chrysanthemums) flower in autumn and long-day plants (lettuce, spinach) bolt in midsummer.
- Propagation
- The practice of producing new plants from existing ones. Methods include stem cuttings, leaf cuttings, division, layering, and seed. Most popular houseplants are propagated by cuttings or division because they preserve cultivar traits. Propagation methods explained.
- Root rot
- A condition in which plant roots are killed by fungal organisms, almost always triggered by waterlogged soil. Symptoms include yellow lower leaves, soft stem bases, and a sour smell from the pot. Treated by trimming affected roots and repotting in fresh dry mix.
- Scientific name
- A two-part Latin name in the form Genus species, also called a binomial name. Italicized in print. The system was formalized by Carl Linnaeus in the 18th century and is the universal standard for unambiguously identifying a plant. Common names vary by region; scientific names do not.
- Species
- The basic unit of biological classification. Members of the same species share most genetic material and can interbreed to produce fertile offspring. The second part of a scientific name (lowercase, italicized) indicates the species, for example deliciosa in Monstera deliciosa.
- USDA (United States Department of Agriculture)
- The US federal agency that publishes the Plant Hardiness Zone Map, the standard reference for cold-hardiness zones used by gardeners across the US and internationally. The current map is the 2023 revision. USDA hardiness zone explainer.
- Variegation
- Patches of white, cream, yellow, pink, or red on leaves where chlorophyll is missing or replaced by other pigments. Variegated cultivars need brighter indirect light than their plain green counterparts because they have less chlorophyll to photosynthesize with. Almost always propagated vegetatively because seedlings revert to green.
- WCVP (World Checklist of Vascular Plants)
- The authoritative global checklist of accepted plant species names, maintained by the Royal Botanic Gardens, Kew. Currently lists approximately 350,000 accepted species. Pocket Botanist uses WCVP as its primary species-name reference.