Acid
Soils with a pH below 6.5.

Adventitious buds
Growth buds which appear on the stem instead of the leaf axil.

Adventitious roots
Roots which appear on an above ground stem.

Aeration
The piercing of the lawn using a garden fork or other mechanical methods to allow air to enter the soil and reduce compaction.

Alkaline
Soils with a pH of above 7.3.

Alpine
Low growing rockery perennials.

Alternate
Leaves/buds arising first on one side of the stem then on the other.

Annual
A plant which has a life cycle of 12 months.

Anther
The pollen-bearing part of the flower, on the stamen, the male reproductive organ.

Anti-desiccant
Chemical used to spray on plants to reduce the loss of water when transplanting.

Asexual
Vegetative reproduction, such as division or cuttings.

Awl-shaped
A narrow leaf tapering to a thin point.

Axil
The upper angle between the leaf stalk and its stem.

B

Balled
Plant lifted from the ground with soil attached to the root, often wrapped in Hessian.

Bare-root plant
Nursery plant lifted from the ground with little or no soil attached to the root.

Basal shoot
A shoot growing from the crown of the plant.

Base dressing
Fertilizer mixed into the soil before sowing or planting.

Bastard trenching
Alternate term for double digging.

Bearded
A petal which bears a row or tuft of long hairs.

Bedding plant
A plant used for temporary display.

Biennial
A plant which has a life cycle of 2 years, flowering the second year.

Biennial bearing
Applied to fruit trees which yield a good crop one year but very little in the second.

Bigeneric
Hybrids produced by the crossing of two different genera.

Bisexual
A flower which bears both female and male reproductive organs.

Blanching
A method used for whitening stems of, for example, leeks, by the exclusion of light.

Bleeding
The loss of sap from damaged or severed plant tissue.

Blind
A mature bulb which produces foliage but fails to flower.

Bole
Tree trunk.

Bolting
Premature flowering.

Boss
A prominent ring of decorative stems.

Bottom heat
Under surface heating used to encourage cuttings to root, using electric cables or other methods.

Bract
A modified, often reduced, leaf at the base of a flower.

Brassica
The genus of vegetables which includes cabbages and cauliflower.

Break
A lateral shoot developing as a result of pruning back to an auxiliary bud.

Breaking bud
A bud which has started to open.

Broadcast
A way of sowing seed thinly and evenly onto the ground.

Bud
An unopened bloom.

Bud burst
The phase when buds start to swell, producing leaves or flowers.

Budding
A method of combining two plants, inserting the growth bud of one plant into the stem of another.

Bulb
An underground storage organ made up of swollen fleshy leaves.

Bushel
An Imperial measure of volume of 1.28 cubic ft.

C

Calcareous
Limy or chalky soil.

Calcifuge
A plant which cannot survive on alkaline soil.

Callus
Scar tissue, a result of wounding or at the base of a cutting.

Calyx
The outer ring of sepals to protect the bud.

Campanulate
Bell shaped.

Catch crop
A fast growing crop grown between the harvest of one crop and the sowing of another in the same plot.

Central leader
The central dominate stem of a tree.

Chelate
An organic chemical which can supply nutrients to plants.

Chimaera
A mutation resulting in two types of tissue, for example, a change in petal colour.

Chitting
The germination of seeds before sowing,

Chlorophyll
The green pigment in leaves used in photosynthesis, which uses light to convert carbon dioxide and water into carbohydrates.

Chlorosis
A yellowing of leaves caused by lack of chlorophyll.

Cloche
A low, transparent structure used to protect and speed up growth in the open.

Clone
Vegetative reproduction resulting in identical plants from one single plant.

Compositae
The Daisy Family, each flower bearing florets instead of petals.

Compost (garden)
Decomposed animal or vegetable matter.

Compost (potting or seed)
Rooting medium made from peat or sterilized soil.

Compound fertilizer
A compound which usually uses the three main elements, nitrogen, phosphorus and potassium, required for healthy growth.

Compound flower
A flower made up of florets.

Compound leaf
A leaf composed of two or more leaflets.

Conifer
A plant which has cones as its seeds.

Contact insecticide
An insecticide which kills pests by direct contact.

Container grown
A plant that has been grown in the nursery in a pot or container.

Containerized
A plant which has been grown in open ground and is just replanted into a pot for resale.

Cordate
Heart shaped.

Cordon
A tree or shrub with a single stem and spur pruned.

Corm
A swollen stem base used for storage.

Corolla
The inner whorl of petals inside the calyx of the flower.

Corona
The trumpet produced in flowers such as Narcissus.

Corymb
A flat topped inflorescence in which all flowers open at the same time.

Cotyledon
A seed leaf which is usually a different shape from that of the mature plant.

Crock
A piece of broken flower pot placed at the bottom of a container for improved drainage.

Cross
The resulting offspring after cross-pollination.

Crown
The base of an herbaceous plant from which the stems grow upwards and the roots grow down.

Cruciferae
The Cabbage or Wallflower Family.

Cultivar
Meaning cultivated variety, originating in cultivation, not in the wild.

Cutting
A method of propagation using root, stem or leaf. For more information see our guide to cuttings.

Cyme
A flat topped or domed inflorescence in which the central flowers open first.