Design the house for the climate that will kill the crop

A closed cover multiplies whatever the site already does. In heat it cooks. In frost it still freezes if the envelope leaks and there is no backup. In wind it becomes a sail. In dull winters it stretches plants that never see enough light. Decide that dominant threat before you choose glazing, heaters, or a hydroponic channel.

Seedlings, fruiting tomato, and NFT greens do not want the same house. Use decides layout, pollination, and how hard climate control must work. Do not copy a neighbour's tunnel if your killing season is the opposite of theirs.

If last season's loss was cooked midday plants or a collapsed hoop, fix climate fit before you buy another bench.

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