Deciduous—Foliage drops in fall and returns in the spring.
Desiccation—Drying out and dying.
Diatomaceous earth (DE)—The skeletal remains (silica compounds and trace minerals) of diatoms—single-celled aquatic algae. An effective insecticide that works by the microscopic particles cutting an insect’s waxy outer coat and destroying its moisture balance.
Dioecious—Male and female flowers on different plants.
Division—Cutting or dividing root clumps and replanting.
Dormant—A period of time that a plant is not growing, normally winter.
Dwarf—A plant whose size has been reduced, either by nature or by vegetative means, such as grafting or budding onto a dwarfing understock. Many annuals have been hybridized to produce dwarf forms from seed.