Convert between Celsius, Fahrenheit, Kelvin, and calculate dew point for greenhouse management.
Convert temperature between Celsius, Fahrenheit, and Kelvin, plus calculate dew point from temperature and relative humidity. Essential for greenhouse management, frost protection planning, storage condition monitoring, and determining spraying conditions. Free and instant.
You ventilated your greenhouse when the thermometer read 28°C, thinking that was the trigger point. But your thermometer was in direct sun — actual canopy temperature was 35°C, and humidity was 92%. By the time you noticed, botrytis had spread across 30% of your tomato crop. Temperature and humidity must be measured together, at canopy level, not eye level.
Critical environmental factors affecting crop growth, pest pressure, and storage.
Temperature at which air becomes saturated. Below dew point, condensation occurs — major cause of fungal diseases in greenhouses.
A: Dew point is the temperature at which air becomes saturated (100% relative humidity) and condensation begins. When leaf temperature drops below dew point, water condenses on leaves — creating ideal conditions for fungal diseases (botrytis, powdery mildew, downy mildew). In greenhouses, ventilate before dew point is reached to prevent disease.
A: Cool-season (lettuce, spinach, broccoli, peas): 15-20°C (59-68°F). Warm-season (tomato, pepper, cucumber, corn): 20-30°C (68-86°F). Hot-season (melon, okra, sweet potato): 25-35°C (77-95°F). Growth stops below 10°C (50°F) for most warm-season crops and above 35°C (95°F) for most cool-season crops.
A: Methods: row covers (frost cloth adds 2-4°C protection), irrigation (spraying water before dawn releases heat as it freezes — protects to -2°C), wind machines (mix warm upper air with cold surface air), heaters (propane/paraffin for high-value crops), smudge pots (less efficient, smoke not heat). Monitor forecasts and act before temperature drops below 0°C (32°F).