The Ultimate Gardening Glossary

A

Acidic soil

Soils with a pH of below 7, which is a favourite of moss. Often, you will find moss growing from acidic soil. Read our guide to tackling moss here.

Adventitious root

A root that arises from any organ other than primary or seminal roots.

Aeration (mechanical)

Within gardening, aerating is the process of providing more oxygen to a lawn. Aerating can also help provide additional nutrients deep within the soil and increase drainage. See cultivation. Learn more in our guide to aeration and scarifying here.

Alkaline soil

Soils with a pH of above 7. A highly alkaline soil can potentially stop absorbing nutrients, which is known as ‘Nutrient Lockup’. Learn more in our guide to natural garden fertilisers.

Annual, summer

Plant that completes its life cycle from seed in one growing season over the summer.

Annual, winter

Plant that initiates growth during the autumn, lives over winter, and dies after producing seed the following season.

Apical meristem

An apical meristem is the growth zone found at the tips of a plant’s roots and shoots, where cells keep dividing to make new tissues. The apical meristem is responsible for the plant’s lengthwise growth, helping roots grow deeper into the soil and shoots grow taller above ground.

Auricle

Claw-like appendages which occur in pairs, appearing at the base of the leaf blade.

B

Bench setting

The height at which the bottom blade of a mower is set above a firm level surface. This is an adjustable setting on many lawn mowers.

Blade

The flattened portion of the leaf located above the sheath.

Brush

To move a brush against the surface of a turf to lift non-vertical stolons and/or leaves before mowing, with the end goal of producing an upright stand of grass. Brushing in different directions can be used to create 'lines' within a lawn.

Bunch-type growth

The process of the plant developing itself through tillering at or near the soil surface without the production of stolons or rhizomes.

C

Carbohydrate

A compound of carbon, hydrogen and oxygen, as in sugar, starch and cellulose. This is the plant’s food source.

Castings (Earthworm)

Soil and plant remains which are excreted by earthworms and deposited on the turf surface or in the burrow, forming a stable soil granule that can be objectionable on mown turf.

Clippings

Leaves - and in some cases, stems - deposited on the turf surface after mowing.

Collar

Light-coloured band at the junction of the leaf blade and the leaf sheath.

Coring

A method of turf cultivation by which soil cores are removed using hollow tines.

Compaction

The compression of soil particles leading to unfavourable growing conditions for the turf grass plant.

Creeping growth habit

Plant development by an extravaginal stem growth at or near the soil surface with lateral spreading rhizomes and/or stolons.

Crown

A highly compressed stem located at the base of a vegetative aerial shoot.

Culm

The flower stem of the grass plant.

Cultivar

An assemblage of cultivated plants distinguished by any characters (morphological, physiological, and the like) that when reproduced sexually or asexually retain their distinguishing features.

Cultivation

Applied to turf, cultivation refers to the working of the soil and/or thatch without destruction of the turf grass surface; for example, coring, spiking, or other means.

E

Evapotranspiration

The loss of water or moisture from the turf grass leaf and the soil surface to the atmosphere. This is more common on hot days. Learn how to tend to your garden in hot weather with our guide to managing a heatwave.

F

Fertiliser

A solution or solid substance that, when applied to plants, can encourage growth by supplying essential nutrients and increase fertility. Adding too much fertiliser can kill plants and turf; always read the label before application. Learn more with our guide to using fertiliser.

G

Germinate

The very first stage of a plant’s life, when a seed begins to sprout and develop shoots and is ready to be planted.

I

Irrigation, automatic

Hydraulic-electric control of water application in response to turf grass needs.

Irrigation, manual

Irrigation using hand set or hand-valved equipment.

L

Lateral shoot

A shoot originating from a vegetative bud in the axil of the leaf or from the node of a stem, rhizome or stolon.

Layering, soil

Undesirable stratification within the surface horizons of a soil profile; can be due to construction design, top-dressing with different textured materials, or inadequate mixing.

Leaching

Loss of nutrients (ionic form) through natural drainage of the soil’s solution.

Ligule

Membranous or hairy appendage on the adaxial side of the grass leaf at the junction of the leaf blade and leaf sheath.

Liquid fertilisation

A method of applying fertiliser using liquid as the carrier. Applied as a liquid solution.

M

Mat

A tightly intermingled layer of our lawn turf, composed of living and partially decomposed stem and root material and soil that develops below the thatch layer but above the soil surface.

Micro organism

Minute living organisms such as bacteria or fungi.

Monocot

Plant having one cotyledon in the seed; grasses are an example.

Mowing frequency

The number of times a turf grass sward is mown per week, month or growing season. Learn the ideal frequency of mowing with our guide to mowing your lawn.

Mowing height

The distance above the ground at which the leaf is cut by a mower’s blade.

Mulch

Any non-living material that forms a covering on the turf grass or soil surface.

N

Nitrification

Formation of nitrates and nitrites from ammonia by soil microorganisms.

Node

The joint of a stem; the region of attachment of leaves to a stem.

P

pH level

Per hydrogen or the negative logarithm of the hydrogen ion concentration of the soil. To find out how to test the pH level of your soil, read our guide to soil types in turf laying.

Pollinate

When pollen is taken from one plant to another, for fertilisation purposes to allow new plant seeds to be produced.

R

Root zone

A prepared mixture of minerals and organic matter used as a growth medium for turf grass.

Rhizome

A plant stem that grows horizontally.

S

Seminal root

The primary root that develops from the plant.

Settling, soil

A lowering of the soil surface resulting in a decrease of volume to a soil previously loosened by some form of cultivation (bare soil). Occurs naturally but can be accelerated by mechanical tampering or heeling in the surface after cultivations have taken place.

Sheath

The tubular basal portion of the leaf enclosing and wrapping around the stem.

Slowly available fertiliser

Designates a rate of dissolution less than that obtained for completely water-soluble fertilisers; may involve compounds that dissolve slowly, materials that must be microbially decomposed, or soluble compounds coated with substances highly impermeable to water.

Soil modification

Alteration of soil characteristics by soil amendment; commonly used to improve physical conditions.

Soil probe

A cylindrical soil sampling tool with a cutting edge at the lower end.

Spiking

A method of turf cultivation in which solid tines or flat pointed blades penetrate the turf and soil surface.

Stand

A number of established individual turf grass genus and species.

Stolon

An elongated stem (or shoot) that grows along the surface of the ground and from which leaves and adventitious roots develop at the nodes.

Stomates (Stoma, Stomata)

Openings in the epidermis of leaves and stems that function in the exchange of gases between the atmosphere and the plant.

Sub-soil

The soil elevation established so that the top-soil placed on it will have the desired thickness and final grade or elevation.

T

Texture, leaf

Texture imparted to turf by leaf width and arrangement.

Texture, soil

The relative proportions of mineral matter found in soil.

Thatch

A layer of undecomposed or partially decomposed organic residues situated above the soil surface but below the turf grass leaves. Consists of all parts of the turf grass plant. Learn more about how to control lawn thatch in your garden here.

Thatch control

The process of (a) preventing excessive thatch build-up by cultural manipulation and/or (b) removing excess thatch from a turf surface by either mechanical or biological means.

Tiller

A lateral shoot, usually erect, that develops intravaginally from buds.

Top-dressing

A prepared soil mix added to the surface of a turf and worked in by brushing, raking and/or irrigating to produce a smooth surface. Firms turf by working soil in among stolons and thatch-forming materials. Also enhances thatch decomposition.

Tufted

See bunch-type.

Turf

A covering of mown vegetation, usually turf grass, growing intimately with an upper soil layer of intermingled roots and stems. A species or cultivar of grass, usually of spreading habit, that can be maintained as a mown turf. Turf is usually sold in rolls of one square metre and is known as sod in America.

Turf grass community

An aggregation of individual turf grass plants that have a mutual relationship with the environment as well as among individual plants.

U

Urea formaldehyde

A synthetic slowly soluble nitrogen fertiliser consisting mainly of methylene urea polymers of different lengths and solubilities; formed by reacting urea and formaldehyde.

V

Variety

See cultivar.

Vertical mower

A mechanical device with vertically rotating blades that cut into the face of the turf for the purpose of reducing thatch and improving gaseous exchange.

W

Wear

The collective injurious effects of traffic (foot or mechanical) on the turf grass plant.

Online Turf shares over 25 years of grass and turf experience through a practical knowledge base full of tips to help your garden thrive as a healthy, green space. If you have any questions about turf or lawn care, the customer service team can offer further guidance and information.