Acid soil - these are soils with a pH below 7.0. Rhododendrons, azaleas and ericas prefer acid soil although most plants prefer acidic soil of a pH around 6.5. However, some plants, such as brassicas need lime to be added to an acidic soil, in order for them to thrive.
Alkaline soil - these soils have a pH above 7.0. Most plants prefer slightly alkaline soil, apart from plants such as rhododendrons, which prefer acidic soil.
Alpine plant - a term used loosely to describe rockery plants. In the wild, these grow above the tree line and below the snow line.
Annual - a plant whose life cycle lasts one year.
Apex - the uppermost bud on a stem.
Aquatic - plant that grows in water, with all, or some of the leaves submerged, i.e. water lilies.
Bedding plants - plants grown mainly for temporary, ornamental displays. Displays tend to be changed frequently according to the seasons. Generally annuals or half-hardy plants raised in greenhouses. Popular in private gardens, municipal parks and roadside displays in town centres.
Biennial - a plant whose life cycle is two years.
Biological control - an environmentally-friendly method
of pest control that relies on the use of natural predators, parasites or
diseases of the targeted pest. Ladybirds can be introduced which will feed
on aphids, encarsia wasps on whitefly etc. The predators target specific pests
without damaging plants or other insects.
Bleeding - sap which flows from cut surfaces of plants.
Bolting - a term used for vegetables which develop a flower stem, usually due to drought or poor soil conditions, e.g. leeks, lettuce.
Brassicas - these plants have tap-roots and branching stems, e.g. swede, turnip, cabbage, sprouts etc.
BTO - British Trust for Ornithology. Promotes bird conservation, mainly through volunteer-based surveys. BTO website
BSA - Birdcare Standards Association. A non-profit organization, dedicated to setting standards for those producing and selling food and other products related to birds. BSA website
Bulb - a bud, serving as a storage organ for the young plant. Usually underground, they have either fleshy or overlapping leaves.
Bulbils - ‘baby’ bulbs produced around the base of a mature bulb, such as daffodils, or on stems, as in lilies. They can be detached and grown.
Calcareous soils - chalky soil, formed on chalk or limestone, with large amounts of calcium carbonate.
Catkin - spikes of flowers, can be male or female, seen on willows and hazel.
Clay soil - a heavy soil made up of fine particles which cling together stickily. Poorly drained.
Cloche - cover made of glass, rigid plastic or polythene, to provide protection to plants. Helps warm the soil and advances growth.
Cold frame - an unheated box made of glass or rigid plastic. Used to protect plants and seedlings from rain and wind. Provides some insulation to half-hardy plants over winter.
Compost - well rotted organic matter. Also term used to describe seed and potting mixtures of loam, sand, peat and leaf-mould.
Conifer - an evergreen tree which usually has cones.
Coppice - undergrowth which is repeatedly cut, providing regrowth for cutting. Good sustainable resource.
Cordon - a plant with one main stem, sometimes two or three. Most commonly used for fruit trees.
Corm - a thickened underground plant stem which stores food. Shoots appear from a bud at the top of the corm.
Crown - basal part of a plant, from where roots and shoots grow.
Cucurbits - gourds, squashes, pumpkins.
Cultivar - a cultivated plant variety.
Cutting - a section of stem, root, or leaf cut from a plant and encouraged to grow roots, to make a new plant.
Damping down - increasing humidity in a greenhouse by wetting the floors.
Dead-heading - removal of dead flowers to encourage more flowers or growth, for example, with roses and sweet peas.
Deciduous - plants and shrubs which lose their leaves before winter.
Detritus - dead and decaying organic matter.
Dormant - a long period of little or no growth in a plant, normally during autumn or winter.
Drill - a shallow trench made in soil. Seeds are sown and the earth replaced on top.
Earthing up - hoeing soil up around plants, usually potato crops, leeks and celery.
Emergents - plants which grow at the edge of a pond. Also called ‘marginals’.
Erosion - the loss of topsoil by the action of wind or rainwater.
Evergreen - a plant with leaves on it all year.
Exotic - plants introduced from another country.
Fauna - animals.
Fertiliser - contains nutrients which are introduced to the soil and are beneficial to plants.
Fleece (horticultural) - a soft plastic used to raise the temperature. Allows air and rain through.
Flora - vegetation.
Foliar feeding - dilute fertilizer applied to leaves.
Forcing - the use of additional heat to ‘force’ vegetables, plants and flowers to produce early crops.
Frost-free - an environment maintained at a minimum temperature of 4ºC (40ºF).
Fruit - the seed of a plant, which can be edible.
Genus (Genera, pl.) - a botanical classification that identifies groups of species with common characteristics, e.g. prunus, betula.
Green manure - plants which are grown purely to dig into the soil to increase soil fertility.
Ground cover - plants that have a low, spreading habit which quickly cover bare ground.
Habit - how a plant grows, e.g. ‘climbing’ or ‘creeping’.
Half-hardy - can be grown in sheltered areas in the south or west. Can be grown in the summer in other parts of the country. Applies to shrubs and perennials as well as annuals and bedding plants.
Hand pollination - where a paint brush is used to transfer the pollen from one flower to another.
Hardening off - gradually exposing plants to lower temperatures by moving them from greenhouses to cold frames, so they can acclimatize and be planted outside.
Hedgerow - a line of bushes and sometimes trees.
Herb - generally thought of as plants used in cooking. Also used medicinally and for dyes or perfumes.
Herbaceous perennial - plants with soft stems which die down each Winter and reappear in Spring.
Herbicide - a weedkiller.
Hip - fruit of a rose, e.g. ‘rose hip’.
Hoary - leaves or stems with short, white or grey hairs.
Hoe - hand too, used to remove weeds.
Humus - well rotted compost or leaf mound.
Hybrid - a plant which is a cross between different species, or varieties of plant.
Improved soils - soils which have had nitrogen added by the use of fertilizers or manure.
In-the-green - bulbs which are transplanted when they have leaves, such as snowdrops.
June drop - a proportion of immature fruits which fall in early summer, the extent of which is affected by moisture levels.
Kernel - a whole seed or the softer, edible, part of a seed encased in a hard shell. Sweetcorn kernels are the yellow grains which make up the cob.
Leaching - minerals in soil which are dissolved and washed away by rainwater.
Leaf litter - leaves which have fallen and collect under vegetation.
Legume - plants with seeds in pods, e.g. peas, beans, lupin.
Lime - fine particles of calcium carbonate (limestone or chalk) added to soil to make it more alkaline.
Loam - fertile soil, rich in minerals, water retentive and has a good level of humus, sand, silt and clay.
Log Garden - a pile of logs left in a bed which provides shelter for insects, hedgehogs etc.
Manure - organic material such as animal or plant matter, which acts as a fertilizer.
Marginals - plants which grow at the edge of a pond, in shallow water. Also known as ‘emergents’.
Meadow - grass with wild flowers grown in it.
Mulch - a layer of well-rotted manure, compost, chipped bark or decorative chippings, placed around plants, to suppress weeds. Helps to retain moisture in the soil.
Naturalised - plants grown so as to look as if they are in natural settings, such as bluebell bulbs grown in a woodland setting.
Neutral - soil that is neither acid or alkaline and which has a pH of between 6.5 and 7.0.
Nutrients - plant foods such as nitrogen and potassium.
Organic - term to describe substances produced from a living organism, such as compost.
Oxygenators - pond plants which add oxygen to the water.
Peat - organic material formed over hundreds of years, in bogs of lifeless water. Non-sustainable resource.
Peduncle - stalk of a flower.
Perennial - plants which live for many years.
Pergola - wooden framework used in seating areas and for growing climbers.
Pinch out - the removal of the growing tip of a plant. Encourages sideshoots or flower buds. Used for plants, such as fuchsias, to make them bushy.
Plug plants - seedlings grown singly which can be potted on with minimal disturbance of roots.
Pollination - the transfer of pollen grains onto a female stigma. Pollination can take place by gravity, insects, wind or by hand, with a soft brush.
Pot-bound - a pot-grown plant, taking up all the available space in its container, sometimes with roots coming through the bottom of the pot. When repotting, tease out the roots to encourage them to grow into the new compost.
Pricking out - term used for removing excess young seedlings from pots, drills or seed trays.
Propagator - a covered, heated unit used to root cuttings and germinate seeds.
Proprietary - used to describe products produced under a brand name, e.g. proprietary compost such as John Innes No. 2.
Raised bed - bed contained by planks, walls, sleepers etc. Allows soil to be raised by a few inches or high enough for wheelchair gardening.
Rhizome - horizontal underground plant stem, e.g. iris and lily-of-the-valley.
Rock garden or rockery - well drained garden with rocks and alpine plants.
RSPB - The Royal Society for the Protection of Birds.
Runner - an aerial stem growing horizontally, which, when in contact with moist soil, roots and produces new plants, e.g. strawberries.
Sandy soil - well drained with large particles.
Saprophytic - a plant or fungus that gains nutrition from decayed organic matter.
Scarifier - a mechanical rake, similar to a cylinder mower which rakes the thatch (dead grass) from lawns.
Scion - a shoot cut from one plant, grafted onto a rootstock, to produce a new plant, used extensively on roses.
Seedbed - an area prepared to a fine tilth for sowing seeds. Seeds can be sown to a consistent depth, with good soil aeration and water penetration.
Semi-evergreen - a plant which may lose its leaves in a bad winter.
Sessile - stalkless flower that comes straight from the stem.
Set - flowers that have been fertilised and are developing fruit or seed. When buying onion bulbs, they are usually purchased as sets.
Shrub - branching perennial with woody stems.
Soil conditioner - manure, etc. dug into soil to improve it.
Stolon - horizontal stem or branch which roots along its length, producing new plants.
Stratification - exposing seeds or bulbs to cold temperatures to simulate winter and encourage them to germinate.
Sub-shrub - low-growing, spreading shrub.
Subsoil - the soil beneath the immediate topsoil.
Successional - sowing at regular intervals to ensure continuous supply of crops.
Sucker - shoot that rises from roots or underground stems. Often appear on roses and should be removed as these are not identical to the main plant.
Sustainable - resources that can be produced forever, such as compost.
Sward - plants that make up turf.
Taproot - central root of many plants, with network of smaller roots branching off.
Tender perennial - perennial plant which may die if subjected to low temperatures.
Tendril - filaments used by climbing plants to hang onto structures, e.g. passion flowers.
Tilth - a fine, crumbly, soil structure, ideal for sowing seeds.
Top dressing - decorative dressing applied around plants or the application of fertilizer, soil or compost to borders, pot plants or lawns, to add nutrients.
Topsoil - the uppermost layer of soil where organic matter is contained.
Tree - very tall, woody stemmed plant.
Truss - clusters of flowers or fruits, e.g. tomato.
Tuber - underground storage organ, e.g. potato, dahlia.
Var. - varieties of plant within a species.
Variegation - leaves with two or more colours, usually white, cream or yellow, e.g. ivy.
Variety - varieties of plant within a species.
Waterlogged - soil saturated with water. Can result from overwatering, compaction or natural defects in the land.