Gardening

A cold floor drains heat from your greenhouse. Here’s how to insulate the ground using foam and membranes while keeping ventilation clear of Building Regulations.

Don't let a hard frost wipe out your greenhouse harvest. Learn how to insulate a greenhouse for winter using bubble wrap, and discover the trade-offs between light, heat, and durability.

H2 plants will not survive a freeze, so hold the greenhouse frost-free. Half-hardy H3 plants are the unheated-house group.

Buy an electric heater sold for greenhouses, with a thermostat, sized to the glass. A tube is background heat. A room fan stays indoors.

Line the glass with horticultural bubble wrap, shut the draughts, and leave the vents able to open. A heater comes after that.

Transplant shock kills more seedlings than frost ever does. This hardening-off routine cuts losses in UK cold frames without complicated kit.

Closed cold frames can hit 20°C above outside air temperature. These ventilation techniques stop scorched crops and damp-related disease before they start.

High humidity in cold frames spreads slugs, aphids and mould fast. These organic fixes stop the spread before it wipes out an entire tray.

Waterlogging and wind-chill can destroy tender plants in unmanaged cold frames, but simple ventilation and insulation tweaks ensure they thrive come spring.

You lift the lid and your lettuce has wilted. A cold frame micro-climate fighting you is fixable — here is how to diagnose and correct the most common problems.