Garden Glossary

Whether you're just getting started in the gardening world, or you're full of hands on experience, you are bound to stumble upon a word every now and then that leaves you at a loss. We've compiled the following list of common terms for you. Can't find what you're looking for? Send an email to and we'll be sure to add it to the list.

Just click the letter of the word you're looking for to skip to that section.

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Acid Soil - A soil with a pH lower than 7.0 is an acid soil. A soil with a pH higher than 7.0 is an alkaline soil. The pH is the measure of lime (calcium) contained in your soil.

Acre - A measure of land totaling 43,560 square feet. A square acre is 208.75 feet on each side.

Aerate - To loosen or puncture the soil to increase water penetration.

Air Layering - A specialized method of plant propagation accomplished by cutting into the bark of the plant to induce the formation of new roots.

Alkaline Soil - A soil with a pH higher than 7.0 is an alkaline soil. A soil with a pH lower than 7.0 is an acid soil. The pH is the measure of lime (calcium) contained in your soil.

Annuals - Plants whose life cycle lasts for only one year or one growing season.

Arboretum - A garden with a large collection of trees and shrubs cultivated for scientific or educational purposes. (Highland Park right here in Rochester, NY is actually an arboretum - the whole park was completely planned, but designed to appear as if it occurred naturally).

Aquatic Plants - Plants which grow in, live in, or live on water.


Balled & Burlapped - A tree which is dug out of the ground with a ball of soil around the roots. The soil ball is usually covered in burlap and wrapped with string or a wire basket for support.

Bare Root - Plants offered for sale which have had all of the soil removed from their roots.

Bedding Plant - A plant that has been grown to blooming or near blooming size before being planted out in a formal area for seasonal display of colorful flowers or foliage.

Biennial - A flowering plant that takes two years to complete its biological lifecycle. Many fruit and vegetable plants are biennial - they bare fruit their second year.

Bolting - Vegetables that quickly go to flower rather than producing the food crop. Usually caused by late planting and temperatures that are too warm.

Bonsai - An ornamental tree or shrub grown in a pot and artificially prevented from reaching its normal size.

Bract - A modified leaf or scale, typically small, with a flower or flower cluster in its axial. Found on Dogwoods and Poinsettias.

Bud - A compact knob-like growth on a plant that develops in a leaf, flower, or shoot.

Bulb - A rounded underground storage organ that contains the shoot of a new plant.


Cambium - A thin layer of generative tissue lying between the bark and the wood steam, most active in woody plants.

Catkin - Usually dense, cylindrical, often drooping cluster of flowers found in willows, birches, and oaks.

Characteristic - Traits or qualities of a tree, such as its leaf color, flowers, fruit, shape, size, structure, etc.

Chlorophyll - A green pigment, present in all green plants, which allows plants to absorb energy from light.

Cladode - A flattened leaf-like stem. It is flat for increasing the surface area, thick for storing water, and green for photosynthesis.

Clump Form - A tree that has more than one trunk.

Complete Fertilizer - A fertilizer which contains all three primary elements: Nitrogen, Phosphorus and Potassium.

Compost - Decayed organic material used as a plant fertilizer.

Conifer - A cone-bearing tree or shrub, often evergreen, usually with needle-like leaves.

Container Grown - Plants, trees and shrubs raised in a pot. The pot is removed before planting.

Cover Crop - A crop grown for the protection and enrichment of the soil.

Crown - The area where the stem meets the roots.

Cultivar - A variety of plant that is grown for its specific characteristics that may not be present with the original species.

Cultivate - Prepare and use (land) for crops or gardening.

Cuttings - A piece cut from a plant for propagation.


Damping Off - A plant disease caused by fungus; diseased condition of seedlings in excessive moisture.

Deadheading - Refers tot he removal of dead or spent blooms to encourage more flowering or to improve the appearance of the plant.

Dibble Stick - Is a pointed wooden stick for making holes in the ground so that seedlings or small bulbs can be planted.

De-thatch - Process of removing dead stems that build up beneath lawn grasses.

Dioecious Plant - A plant species in which male and female organs appear on separate individuals. In order to produce fruit and viable seeds, both male and female plants must be present.

Dividing - The process of splitting up plants, roots and all, that have been bound together. This will make several plants from one plant, and usually should be done to mature perennials every 3 to 4 years.

Dormancy - A state of reduced activity that enables plants to survive conditions of cold, drought, or other stress.

Double Digging - Preparing the soil by systematically digging an area to the depth of two shovels.

Double Flower - Varieties of flowers with extra petals, often containing flowers within flowers.

Drip Line - The imaginary circle that you would draw on the soil around a tree directly under the outermost branch tips. (Where the snow drips when it melts off the branches).


Easement - A portion of land where utilities are located that can be publicly or privately owned.

Epiphyte - A plant which grows on another plant but gets its nutrients from the air or rainfall. Examples include ferns, bromeliads, air plants and orchids.

Erosion - The gradual destruction either by wind, water, or other natural agents.

Espalier - A fruit tree, tree, or shrub whose branches are trained to grow flat against a wall (or supported on a lattice) by pinching or pruning the branches.

Evergreen - A plant that retains green leaves throughout the year.

Evaporation - A change in phase in the atmosphere occurs when substances change from liquid to gaseous, or vapor, form.

Exotic Species - A tree species that has been imported from another region and does not grow naturally in the region it is being planted.

Eye - An undeveloped bud growth which will ultimately produce new growth.


Fertilizer - A chemical or natural substance added to the soil to increase its fertility.

Flat - A shallow box or tray used to start cuttings or seedlings and for growing and selling young plants.

Floating Row Covers - A very shear, lightweight fabric that can be simply draped over vegetables to trap heat in during the day and release it at night. Use them in the Spring to fend off pests and in the fall to extend your growing season.

Foliar Feeding - A technique of feeding plants by applying liquid fertilizer directly to their leaves.

Forcing - A technique that imitates the environmental conditions that bulbs encounter outdoors, thereby tricking them into flowering earlier.

Frond - The leaf or leaf-like part of a palm, fern, or similar plant.

Frost - A deposit of small white ice crystals formed on the ground or other surface when the temperature falls below freezing. Tender plants will suffer extensive damage or die when exposed to frost.

Fruit - The fully developed ovary of a flower containing one or more seeds.


Germinate - To cause to sprout; when a plant begins to grow and put out shoots after a period of dormancy.

Girdling - To kill a tree or woody shrub by removing or destroying a band of bark and cambium from its circumference. Gnawing animals, especially rodents can also girdle trees.

Grafting - A shoot or bud of one plant that is inserted into or joined to the stem, branch, or root of another plant so that the two grow together as a single plant. This is often done to produce a hardier or more disease resistant plant.

Ground Cover - Is any plant that grows over an area of ground, used to provide protection from erosion and drought, and to improve its aesthetic appearance.

Growing Season - The number of days between the average date of the last killing frost in Spring and the first killing frost in Fall. Vegetables and certain plants require a minimum number of days to reach maturity.


Habit - The characteristic growth form or general shape of a plant.

Harden Off - To gradually acclimatize a plant to a more harsh environment. A seedling must be hardened off before planting outdoors.

Hardiness Zone - Used to indicate geographic limits of the cold hardiness of different species, subspecies, genera or clones. The hardiness zone of Rochester, NY is 6a.

Hardpan - A hardened impervious layer, typically of clay, occurring in or below the soil.

Heading Back - Pruning shoots back one-half to one-third to buds or twigs with potential for encouraging new growth.

Herbaceous - Plants with non-woody stems. They have soft or succulent green stems that will die back to the ground in the winter.

Humus - The organic component of soil, formed by the decomposition of leaves and other plant material by soil microorganisms.

Hybrid Deciduous - The offspring of two parent trees belonging to a tree that drops its leaves every year.

Hydroponics - Cultivation of plants in nutrient solution other than soil.


Inflorescence - The complete flower head of a plant including stems, stalks, bracts and flowers.




Leaching - The removal or loss of excess salts or nutrients from soil.

Leaf Mold - A disease of plants in which mold develops on leaves, caused by fungus. (Also a soil composed mainly of decaying leaves).

Loam - A fertile soil of clay, sand and organic matter.


Manure - Organic matter used as organic fertilizer and contributes to the fertility of the soil by adding nutrients such as nitrogen, that is trapped by bacteria in the soil.

Maturity - The point of being fully grown and reaching the potential height and width.

Micronutrients - There are about seven nutrients essential to plants growth and health that are only needed in very small doses. These nutrients are manganese, boron, copper, iron, chloride, molybdenum and zinc. Sulfur is also considered a micronutrient, but is listed as a macronutrient.

Mulch - A material such as decaying leaves, bark or compost that is spread around or over a plant to enrich or insulate the soil, retain moisture, control weeds, and/or prevent roots from freezing. Plastic sheeting and other commercial products can also be used.


Native Species (Native Plant) - A plant that grows naturally in a specific region or location.

Node - A point on a plant stem from which the leaves or lateral branches grow.

Nut - A hard, bony, one-celled fruit that does not split such as an acorn.


Ordinance, Tree - An enforceable tool for the city or town that mandates proper tree care, gives force and direction to professional tree care performed by anyone in the community on public trees, and gives size and placement planting requirements for small, medium and large trees to enchance, preserve and protect the health of the urban forest.

Organic Gardening - A method of gardening where all materials used in the garden come from natural sources and was not chemically produced by man.


Panicle - A loose branching cluster of flowers, such as oats.

Parasitic Plant - One plant living on another plant and obtaining organic nutriment from it.

Peat Moss - Partially decomposed remains of various masses such as vegetation matter. Often used to retain moisture in soil.

Perennial - A non-woody plant which grows and lives for more than two years.

Perlite - A variety of obsidian consisting of masses of small pearly globules, used as a soil conditioner in potting mixes, to promote moisture retention white allowing good drainage.

Pest - An insect or other small animal that harms or destroys garden plants, trees, etc.

pH - The measure of lime (calcium) contained in your soil. Soil with a pH lower than 7.0 is an acid soil, while soil with a pH higher than 7.0 is an alkaline soil. (Soil can be tested with an inexpensive soil test kit).

Photosynthesis - The process by which green plants and certain other organisms use sunlight to synthesize foods from carbon dioxide and water.

Pinching Back - Nipping off the very tip of a branch or stem. Pinching promotes branching and a bushier, fuller plant.

Pistil - The female part, or seed-baring part of the flower.

Pollination - The transfer of pollen from the stamen (male part of the flower) to the pistil (female part of the flower), which results in the formation of a seed. (Hybrids are created when the pollen from one kind of a plant is used to pollinate an entirely different variety, resulting in a new plant.)

Potting Soil - A mixture used to grow plants, herbs and vegetables in a container garden or in a pot. Potting mixes should be sterile, loose, and light. A mixture of loam, peat, perlite or vermiculite and nutrients is preferred.

Propagation - To reproduce new plants either by cuttings or layering.

Pruning - The cutting or trimming of plants or trees to remove dead or over-grown branches and stems. To control and promote new growth.



Raceme - A single-stemmed inflorescence with flowers on individual stalks along a stem. The bottom flowers open first as the raceme continues to elongate. Snapdragon and delphinium flowers grow on racemes.

Relative Humidity - The ratio of the amount of moisture that exists in the atmosphere.

Rhizome - A continuously growing horizontal underground stem that puts out lateral shoots from its nodes. Also called rootstock. (Some lawn grasses and irises are rhizome plants.)

Right-of-Way - An area between private property line and the street owned by a town or city.

Root - The underground portion of a plant, tree or shrub that serves as an anchor and absorbs water and minerals from the soil.

Root Ball - The roots and accompanying soil when the plant/tree is taken from its growth site and transported. The root ball should be kept intact when transplanting.

Root Bound (Pot Bound) - When a plant has grown too large for its container, resulting in matting and entangling of the roots. This will stunt the growth of the plant. When re-potting, gently loosen the roots on the outer edges of the root ball, to induce outward growth.

Rooting Hormone / Rooting Powder - Is either a powdered or liquid hormone that when applied to the base of a cutting, stimulates root formation.

Rosette - A cluster of leaves or flowers growing in crowded circles from a common center or crown, usually at or close to the ground.

Runner - A shoot, typically leafless, that grows from the base of a plant along the surface of the ground and can take root at points along its length.


Scarification - Allows water and gases to penetrate into the seed including physically breaking the hard seed coats or to soften them with chemicals.

Scion - The short length of stem that is grafted onto the rootstock of another plant (usually a related plant or species).

Seeds - A plants unit of reproduction capable of developing into another such plant.

Shrub - A woody, perennial plant smaller than a tree, usually with several stems or trunks. Some can be grown as small trees if pruned properly.

Soil pH - Soil pH is the measure of the amount of lime (calcium) contained in your soil. A soil with a pH lower than 7.0 is an acid soil. A soil pH higher than 7.0 is an alkaline soil. Soil pH can be tested with an inexpensive test kit.

Sphagnum - A bog moss which is collected and composted. Most peat moss is composed primarily of sphagnum moss. This moss is also packaged and sold fresh and used for lining hanging baskets and air layering.

Specimen - Trees or shrubs placed conspicuously alone in a prominent place to show off its ornamental qualities; focal piece in the landscape.

Spore - Spores are most common on non-seed baring plants such as algae, moss and fern. Spores are produced by bacteria, fungi and green plants, and are most prevalent in very moist, wet areas.

Staking - A newly planted tree should be staked the first year or so, until it gets established using hardwood stakes, pieces of rubber hose and tree wire. This helps the formation of the tree and keeps it secure in high wind conditions. For more complete details, see our Planting Guide.

Street Tree - Trees growing in the public street right-of-way that is usually owned by a town or city.

Sucker(s) - Shoot(s) that grows from the bud at the base of a tree from its roots. Also known as a basal shoot, root sprout or cane shoots. On a grafted tree, such as a Weeping Cherry, they will appear at the top, and grow upright; they need to be pruned often. Suckers should be removed as they draw energy from the main tree.

Stolon - A low spreading plant stem or runner that produces new plants at the tips, such as strawberry plants or hens and chicks.

Systemic - A chemical absorbed directly into the plant through the roots system and circulated through the tissues to kill feeding insects.


Tap Root - The main primary root that grows vertically into the ground. From that, other roots sprout laterally.

Tender Plants - Plants that are unable to withstand frost or freezing temperatures.

Tendril - The slender, twirling ringlet found on many vines, which allows the plant to attach itself to a trellis, fence, wall or other support such as a grape vine.

Thinning - To remove some plants to allow others more room to grow. It can also refer to removing branches from trees and shrubs to give the plant a more open structure.

Top Dress - To evenly spread a layer of fertilizer, mulch or stone over the surface of the soil.

Top Soil - The layer of soil on the surface that usually has the highest concentration of organic matter and microorganisms.

Transpiration - The release of water vapor through the leaves of plants.

Transplanting - To dig up a plant from one location and plant it in another location.

Tree Lawn - The space where street trees are planted, usually in the public right-of-way and between the street and the sidewalk.

Tuber / Tuberous - Various types of modified plant structures that are enlarged to store nutrients for re-growth the next season (such as a Dahlia).


Umbel - Inflorescence which consists of a number of short flower stalks equal in length and spread from a common point. Examples of umbels are Dill, Queen Anne's Lace and Geraniums.


Variegated - Leaves which are marked with multiple colors.

Vermiculite - A sterile soil mineral created from 'mica' which has been heated to the point of expansion. It is a good soil additive used in potting mixes. It retains moisture and air within the soil.


Woody Plants - Plants that have hard, rather than fleshy, stems and produce buds that survive above ground in the winter.