Req 8b2 — Speaking the Language of Horticulture

These 14 terms are the foundation of every plant-selection conversation a horticulturist has. Learn them well enough to use them naturally—your counselor may ask you to apply them to a specific plant rather than just recite a definition.

The 14 Terms

Hardiness zone — A geographic area defined by average annual minimum winter temperature (USDA system in the U.S.). Knowing your zone tells you which plants can survive your winters outdoors.

Shade tolerance — How well a plant grows with reduced light. Full-sun plants need 6+ hours of direct sun; full-shade plants can thrive with fewer than 2 hours.

pH — A measure of soil acidity or alkalinity on a scale of 1–14 (7 is neutral). Most landscape plants prefer slightly acidic to neutral soil (pH 6–7). Blueberries want pH 4.5–5.5; lilacs prefer 6.5–7.

Moisture requirement — How much water a plant needs to thrive. Ranges from drought-tolerant (cacti, lavender) to consistently moist (cardinal flower, marsh marigold).

Native habitat — The natural environment where a plant evolved—forest floor, prairie, wetland, etc. Matching a plant to conditions similar to its native habitat reduces maintenance.

Texture — The visual or tactile coarseness of a plant’s leaves and stems. Fine-textured plants (ferns, ornamental grasses) contrast with coarse-textured ones (hosta, oakleaf hydrangea) in design.

Cultivar — A cultivated variety selected for a specific trait (size, color, disease resistance) and propagated to keep that trait consistent. Written in single quotes: Hydrangea macrophylla ‘Endless Summer’.

Ultimate size — The maximum height and spread a plant reaches at full maturity under good conditions. Underestimating this leads to plants crowding buildings or each other.

Disease resistance — A plant’s genetic ability to resist common pathogens. Choosing resistant cultivars reduces the need for fungicides (e.g., disease-resistant roses, powdery-mildew-resistant phlox).

Habit — The natural shape or form of a plant: upright, spreading, weeping, columnar, mounding, vase-shaped, etc.

Evergreen — A plant that retains its leaves year-round (needled or broadleaf). Examples: pine, boxwood, rhododendron.

Deciduous — A plant that drops all its leaves seasonally, typically in fall. Examples: oak, forsythia, hostas.

Annual — A plant that completes its entire life cycle (germinate, grow, flower, seed, die) in one growing season. Must be replanted each year.

Perennial — A plant that lives for more than two years, dying back to the roots in cold climates and re-sprouting each spring.

Finding Your Hardiness Zone

Use the USDA Plant Hardiness Zone Map—enter your ZIP code and it returns your zone instantly. Write it down; you’ll use it when building your list of 10 plants.

Building Your Plant List

Your list needs 10 landscape plants that:

1. Are suitable for your hardiness zone
2. You genuinely find attractive or interesting
3. Include the common name and scientific name (genus + species, in italics)

A good format:

Use plant tags at the nursery you visited, the Grow Native! glossary, or the USDA map site to verify hardiness.

Official Resources