MN Landscape key terms

A geographic rating, based on average annual minimum temperature, that indicates which perennial plants are likely to survive winter at a given site. The USDA map is the most widely used version in Minnesota.

The localized climate of a specific spot, such as a south-facing foundation bed or a low frost pocket, which can differ enough from the regional norm to change what will grow there.

A low-lying area where cold air collects and drains poorly, producing colder nights and later spring frosts than surrounding higher ground. It limits plant selection and can damage early blooms.

The slope and elevation of the ground surface, set during construction so water drains away from structures. Proper grading typically falls about 2 percent away from foundations for the first several feet.

A condition in which surface and subsurface water flows away from buildings and paved areas by gravity. It is achieved through correct slope, soil preparation, and outlets for collected water.

A shallow, vegetated or lined channel shaped into the landscape to convey and slow stormwater. Swales reduce erosion compared with bare ditches and can infiltrate water into underlying soil.

A trench filled with gravel and containing a perforated pipe that intercepts and redirects subsurface water. It relieves soggy soils and protects foundations where surface grading alone is insufficient.

A planted depression designed to capture and infiltrate runoff from roofs, drives, and lawns. Correctly sized and sited with suitable plants, it filters pollutants and reduces peak stormwater flow.

A vegetated conveyance channel engineered to filter and infiltrate stormwater as it moves along the slope. It combines the drainage function of a swale with pollutant removal by soil and plants.

A paving unit with open joints or gaps that allow water to pass into a gravel and soil base beneath. Used in hardscape design to reduce runoff and meet stormwater requirements.

The compacted layer of aggregate beneath a paver or concrete installation that spreads loads and provides a stable foundation. Its depth and compaction determine long-term resistance to settling and frost heave.

Upward movement of soil and structures caused when freezing water expands in the ground. In cold climates it lifts pavers, footings, and plant crowns unless foundations extend below the frost line.

A scaled drawing that locates proposed plants by botanical name, size, and quantity. It communicates design intent to installers and serves as the basis for takeoffs and client approval.

A table accompanying a landscape plan that lists each plant symbol, botanical and common name, size, quantity, and remarks. It ensures accurate ordering and consistent installation on site.

A project delivery method in which one firm handles both design and construction, streamlining communication and accountability. It differs from design-bid-build, where separate parties contract for each phase.

A decision-making approach that combines monitoring, cultural controls, biological controls, and judicious pesticide use, applying chemicals only when thresholds are exceeded. It reduces resistance and unnecessary applications.

The pest population or damage level at which control action is justified to prevent unacceptable loss. It guides IPM decisions so treatments are applied only when economically or aesthetically warranted.

Systematic inspection of plants or turf to detect pests, diseases, and disorders early. Regular scouting records population trends and supports timely, targeted management decisions.

A layer of dead and living stems, roots, and organic matter between the green turf canopy and the soil surface. Excessive thatch blocks water and air movement and harbors disease and insects.

Mechanical removal of excess thatch using vertical blades or tines. It restores water and air penetration and is best timed when turf is actively growing and can recover.

Removing small plugs of soil from turf to relieve compaction and improve air, water, and root movement. Holes are usually filled by topdressing or by soil washing back in.

The height at which turfgrass is cut, measured from the soil surface. Cutting too short reduces rooting and invites weeds; the rule of thumb is to remove no more than one-third of the blade at a mowing.

The relative proportions of nitrogen, phosphate, and potash in a fertilizer, expressed as the numbers on the label. A 10-10-10 analysis has a 1:1:1 ratio regardless of concentration.

A fertilizer whose nutrients become available gradually through coatings, chemical form, or low solubility. It reduces leaching and salt injury and is favored for container and nursery production.

Dissolved mineral ions in soil or growing media that can accumulate with irrigation and fertilization. High levels draw water away from roots and cause marginal leaf burn and stunting.

Flushing excess soluble salts from growing media by applying water beyond what the plant uses. It is a standard remedy for salt buildup in greenhouse and nursery containers.

A measure of a solution's ability to carry current, used to estimate soluble salt concentration in media or irrigation water. Growers monitor it to avoid salt injury and nutrient imbalance.

A nursery stock form in which the root system is lifted with a soil ball wrapped in burlap and secured with twine or a wire basket. The ball must be kept intact and moist until planting.

Nursery plants sold with soil removed from the roots, usually dormant and shipped in moist packing. Roots must be kept moist and planted promptly or heeled in before growth resumes.

Plants grown and sold in a pot or container with their root system in a growing medium. Roots may circle the container, so they are often scored or teased apart at planting.

A low, unheated structure with a transparent top that protects seedlings and overwintering plants. It extends the growing season by trapping solar heat while sheltering plants from wind and frost.

Gradually acclimating greenhouse-grown plants to outdoor conditions before transplanting. Exposure to sun, wind, and cooler temperatures is increased over days to prevent shock and sunscald.

A valve or assembly that stops contaminated water from reversing into a potable supply. Irrigation systems connected to municipal water typically require an approved device and periodic testing.

A backflow prevention assembly installed above the highest downstream outlet, using a spring-loaded check and an air inlet to prevent reverse flow. It protects potable water on irrigation systems.

A group of sprinklers or emitters operated together by one valve, sized to match available flow and pressure. Zoning by plant water need, sun exposure, and soil allows independent scheduling.

A low-pressure system that delivers water slowly through emitters directly to the root zone. It saves water by limiting evaporation and runoff and keeps foliage dry, reducing disease.

The combined loss of water from soil evaporation and plant transpiration. Irrigation schedules based on local ET replace only the water the landscape actually uses, improving efficiency.

A design principle in which all sprinklers on a zone apply water at similar rates, so no area is over- or underwatered. It allows uniform run times across differing nozzle patterns and spacings.

The portion of a tree above the root collar, including trunk, branches, and foliage. Its structure and condition are the main focus of pruning and risk assessment work.

The swollen tissue where a branch attaches to its parent stem. A proper pruning cut leaves the collar intact so the tree can seal the wound with callus and defensive tissue.

Pruning young trees to develop a single strong leader, well-spaced scaffold branches, and sound attachment geometry. It reduces future breakage and the need for corrective work on mature trees.

The transition zone where trunk tissue meets root tissue, normally visible at or slightly above grade. Burying it too deep suffocates roots and is a common cause of decline in new plantings.

A root that grows around the trunk or another root and constricts it as both thicken. It cuts off vascular flow, causing slow decline, and often originates in container-grown stock.

Pruning that lowers a tree's height or spread by cutting back to branches large enough to assume the terminal role. It is distinct from topping, which leaves stubs and invites decay.

Damage from cold, desiccation, sunscald, or frost heave during dormancy. Symptoms such as dieback, bark splitting, and bud death often appear the following spring.