Outdoor & Protected Cultivation
Topography, Microclimate & Cold-Air Drainage
Slope, aspect, structures, vegetation, soil moisture, and cold-air movement can make nearby outdoor sites behave differently. Microclimate mapping helps explain repeated hot, humid, windy, or frost-prone zones.
Key concepts
- Cold dense air can settle in low areas during calm clear nights
- South- and west-facing exposures can experience different heat loads than shaded aspects
- Walls and fences can create both shelter and stagnant air
- Vegetation alters shade, wind, humidity, and competition
What to measure or observe
- Place temporary sensors in suspected hot and cold spots
- Map slope and aspect
- Record morning dew persistence
- Compare wind exposure across the site
Common mistakes
- Assuming one yard equals one microclimate
- Placing the only sensor near a building
- Ignoring cold-air drainage
- Treating recurring location-specific stress as a cultivar problem
Visuals this lesson still needs
- Topographic microclimate map
- Cold-air drainage cross section
- Aspect and solar-load diagram
- Dew-persistence site comparison