Back-bulb (of orchids) A dormant, old pseudobulb without leaves.

Backfill To fill in a planting hole around a plant’s roots with a soil mix.

Balled 1) Of trees and shrubs that have been lifted and had their root ball wrapped in hessian or other material to keep it intact during transplanting; 2) of a flower that does not open properly and rots when still in bud.

Bare-root Of plants sold with their roots bare of soil.

Bark-ringing The removal of a ring of bark from the trunk or branches of certain fruit trees to reduce vigorous growth and to encourage fruit cropping.

Basal plate A compressed stem part of a bulb.

Base dressing An application of fertiliser or humus (manure, compost, etc.) applied to or dug into the soil prior to sowing or planting.

Basin irrigation A form of irrigation whereby soil is scooped out from around the plant or made to form a ridge around it creating basin into which water is introduced.

Bed system A method of planting vegetable crops in closely spaced rows, often in blocks or narrow beds for easy access.

Bedding plants Annuals and biennials (or plants grown as such) raised almost to maturity and then planted out, “bedded out”, often in large blocks for temporary display.

Biennial A plant that flowers and dies in the second growing season after germination (see also Annual, Perennial).

Biennial bearing The production of a heavy fruit crop in alternate years, with little or no blossom or fruit in the intervening years.

Blanch To exclude light from developing leaves or stems in order to keep the plant tissue soft and palatable.

Bleed To lose sap through a cut or wound.

Blind Of a plant that fails to produce flowers, or a stem in which the growing point has been damaged.

Bloom 1) A flower or blossom; 2) a waxy, white or bluish-white coating on a stem, leaf, or fruit.

Blown Of flowers or hearted vegetables that are past full maturity and fading.

Bog plant A plant whose natural habitat is soil that is permanently damp, or one that thrives in such conditions.

Bole The trunk of a tree from ground level to the first major branch.

Bolt To produce flowers and seed prematurely.

Bower A shady, leafy shelter or recess (see also Arbour).

Bract A modified, often protective, leaf at the base of a flower or flower cluster. Bracts may resemble normal leaves, or be small and scale-like, or large and brightly coloured.

Branch A shoot arising from the main stem or trunk of a woody plant.

Brassica A member of the cabbage family.

Break A shoot growing from an axillary bud.

Broadcasting Scattering seed or fertiliser evenly over the ground, rather than in furrows or drills.

Broad-leaved Of trees or shrubs that bear broad, flat leaves rather than needle-like foliage.

Bromeliad A member of the family Bromeliaceae.

Bud A rudimentarv or condensed shoot containing an embryonic leaf, leaf cluster, or flower. Adventitious bud: one produced abnormally, for example from the stem instead of from a leaf axil. Apical (or terminal) bud: the topmost bud on a stem. Axillary bud: one that occurs in an axil. Crown bud: a flower bud at the shoot tip surrounded by other usually smaller, flower buds. Fruit bud: one from which leaves and flowers (followed by fruits) develop. Growth bud: one from which only leaves or a shoot develop.

Bud union The point at which the scion bud unites with the rootstock.

Budding Bud-grafting, a form of grafting.

Budwood A shoot cut from a tree to provide a scion for bud-grafting.

Bulb A modified stem acting as a storage organ and consisting mainly of fleshy, more or less separate or tightly packed, scale leaves (a modified bud) on a much reduced stem (basal plate).

Bulb fibre A mixture of peat, oyster shell, and charcoal, in which bulbs are grown in containers, often without drainage holes.

Bulbil A small bulb-like organ, often borne in a leaf axil, occasionally on a stem or in a flowerhead.

Bulblet A small developing bulb produced from the basal plate of a mature bulb outside the tunic.

Bush 1) A small shrub; 2) An open-centre fruit tree with a trunk of 90cm (3ft) or less. Bush fruit: used of soft fruit bushes such as blackcurrants and gooseberries.