Annual -- A plant that normally lives for only one year
Biennial -- A plant that normally lives for two years. Generally they grow leaves and roots the first year, then they bloom the second year.
Compost -- A mixture of decaying organic matter, as from leaves and manure, used to improve soil structure and provide nutrients to plants.
Cross-reactive allergic reactions -- Cross-reactivity occurs when the immune system mistakes a similar protein or chemical composition for an allergen, causing an adverse reaction. The immune system may react to foods or to pollen from plants in the same botanical family.
Damping off -- A term for seedling death by any of a handful of fungal diseases, including root rot or mold.
Deadhead -- The cutting or pinching off of faded flowers. Since the plant is trying to set seed, this encourages it to bloom again. Most annuals and many perennials will continue to flower if deadheaded.
Deciduous -- trees or shrubs that lose their leaves seasonally
Harden off -- The process of allowing plants started indoors to gradually acclimate to the conditions they will have when moved permanently outdoors.
Instar -- A stage in the life of an insect between two successive molts.
Perennial -- A plant that normally lives for three or more years
Tender perennial -- A plant that is hardy in a warmer zone than where you are gardening. A tender perennial will need to be dug up and wintered over in a protected, frost-free place, or grown as an annual.
Transpiration -- The evaporation of water from the leaves of plants. They lose up to 99 percent of the water they gain from their roots to the atmosphere this way.