Backyard greenhouses
A greenhouse stretches your growing season at both ends. These guides help you choose the right type, size and glazing, site it well and pick a kit that suits your climate.
- Our first guides in this section are being written now.
The main types of backyard greenhouse
- Mini and portable greenhouses. Shelving units or small walk-in frames with a plastic cover. Good for starting seeds and protecting a few plants, but light and easily damaged by wind.
- Lean-to greenhouses. Built against a house or garage wall, which adds stored warmth and shelter. A south-facing wall is ideal.
- Freestanding kits. The classic peaked-roof greenhouse in aluminum, steel or wood with glass or polycarbonate panels. Most homeowners buying a kit choose this type.
- Hoop houses. Arched frames covered in polyethylene film. Inexpensive per square foot and popular for larger vegetable plots.
What matters most when choosing
Glazing. Glass transmits the most light and lasts for decades but is heavier and more fragile. Twin-wall polycarbonate insulates better than single glass and is shatter-resistant. Polyethylene film is the cheapest cover and needs replacing every few years.
Frame and anchoring. Aluminum frames are light and rust-free; galvanized steel is stiffer; cedar looks good and insulates better. Whatever the frame, anchor it to a solid, level base. Check the kit's stated wind and snow ratings against your local weather.
Ventilation. Greenhouses overheat fast on sunny days, even in spring. Look for roof vents (automatic openers help), side louvers or a door you can leave open.
Siting. Choose the spot with the most winter sun. In most of the US, that means running the long side east to west so it faces south, away from trees and buildings that cast shade when the sun is low.