Ventilation is life support — trapped sun kills faster than a dry bed

Sun through glazing is a heater you cannot switch off. Without a planned path for hot air to leave, and cooler air to enter, leaf temperature races past what roots can supply. Plants look thirsty while the slab is still wet. Circulation fans mix pockets so one bench is not a sauna and another a swamp.

Check vents, screens, shutters, and obstructions the way you check water: every hot day, not when plants collapse. A timer that opens nothing you can see is not ventilation. Shade cloth and whitewash help after air can move; they do not replace it.

If fruit cooks on the vine at noon while irrigation still runs, open the house before you change the feed.

In this series

• Design the house for the climate that will kill the crop
• Ventilation is life support — trapped sun kills faster than a dry bed
• Prove water, drainage, and backup before you buy a timer
• Moist is not waterlogged — roots need air as much as water
• Space, screens, and a twice-weekly walk beat a late bottle
• Plan backward from harvest; a full green house is not a result