Horticulture Glossary and Landscape Terms Defined
This glossary gives you real definitions for terms you will hear in plant consultations, service proposals, and design layouts. These are not textbook definitions — they are field-applied explanations you will actually understand. Whether you are a homeowner, landscaper, or garden center employee, knowing these terms will help you speak the language of the landscape.
Section 1 — Core Horticulture Terms You Should Know
Annual: A plant that lives for one growing season. It grows, flowers, and dies in the same year. Must be replanted every season.
Perennial: A plant that comes back year after year, typically dying back in winter and re-emerging in spring.
Deciduous: A plant that loses its leaves in the fall or winter. Common in flowering trees and shrubs.
Evergreen: A plant that keeps foliage all year. Includes conifers like arborvitae, and broadleaf types like holly.
Softscape: The living part of the landscape — plants, mulch, soil, and bed materials.
Hardscape: The structural elements in a yard — patios, walls, walkways, edging, and stone features.
Transplant Shock: A plant's natural response to being moved. Causes temporary wilt, leaf drop, or slowed growth.
Mulch: Organic or synthetic material spread over beds to retain moisture, block weeds, and stabilize soil.
Compost: Decomposed organic matter used to improve soil structure and nutrient content.
Root Ball: The mass of soil and roots surrounding a nursery-grown plant. Must be installed at the proper depth.
Girdling Roots: Roots that wrap around a plant’s base or trunk, eventually choking it out.
pH: A measure of soil acidity or alkalinity. Ranges from 0 (very acidic) to 14 (very alkaline). Most plants prefer a slightly acidic pH between 6 and 7.
Drainage: How quickly water moves through soil. Poor drainage causes root rot. Fast drainage can dry roots too quickly.
Loam: Ideal soil blend with good structure. A mix of sand, silt, and clay that retains moisture while draining well.
Clay Soil: Dense and slow-draining. Common in compacted areas. Often needs amendment before planting.
Sun Exposure: How much light a location receives:
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Full sun: 6 or more hours of direct light
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Partial sun: 4 to 6 hours
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Shade: Less than 4 hours
Dieback: The death of plant tips or stems. Often caused by root issues, winter damage, or fungal stress.
Frost Heave: When soil expansion from freezing lifts shallow-rooted plants out of the ground.
Deer Pressure: The likelihood of deer feeding on landscape plants. High-pressure zones require resistant varieties.
Zone (Hardiness Zone): A classification based on the average minimum winter temperature. Determines what plants will survive long-term. NJ is mostly Zone 6 and 7.
Section 2 — Design and Maintenance Terms
Backbone Plant: A large shrub or tree used to anchor a design. Provides height, structure, or privacy.
Filler Plant: A mid-size plant used between larger anchor plants. Adds bulk, color, or seasonality.
Groundcover: Low-growing plants that spread across the soil surface. Used to reduce weeds and hold soil.
Layering: A design strategy that arranges plants by height from back to front to create depth.
Massing: Grouping plants of the same type together for visual impact.
Airflow: Space between plants that allows wind and air to move freely, preventing fungal issues.
Edge Definition: The line or material that separates your planting bed from the lawn or other surfaces.
Thinning: Selective removal of branches or shoots to reduce density, improve air circulation, or shape.
Deadheading: Removing spent flowers to encourage more blooms and tidy the plant.
Cutback: Heavily reducing a perennial’s size after bloom or at season end to trigger healthy regrowth.
Woody Plant: A plant that develops permanent stems or branches, such as trees, shrubs, and evergreens.
Herbaceous Plant: A plant with soft, green stems that typically die back in winter.
Hard Prune: Removing a significant amount of a plant’s size, usually done in early spring or late winter.
Selective Prune: Targeted cutting of specific branches for shape or health, not mass removal.
Root Prune: Trimming roots, usually during transplant or for controlling growth in containers.
Section 3 — Quick-Use Abbreviations and Field Phrases
B&B (Balled and Burlapped): Plants sold with soil-wrapped roots in burlap and wire baskets.
C/T (Container): Plant sold in a plastic or decorative container. Common in nurseries.
Caliper: The diameter of a tree trunk, typically measured six inches above the base.
Flush: A period of new leaf or flower growth.
Leggy: A plant that has grown tall and bare, often from too little light or pruning.
Tight Habit: A plant that grows compact and dense without sprawling.
Open Growth: A loose or airy plant form, sometimes desirable for style or airflow.
Spent: A bloom or shoot that is done growing or dying off.
Staking: Supporting young or newly planted trees with wooden or metal stakes.
Harden Off: Transitioning a greenhouse plant to outdoor conditions by gradually increasing sun and wind exposure.
Sucker Growth: Shoots that sprout from the base or root zone of a plant, often unwanted.