AdewebsI’ve been sowing seeds and nursing seedlings longer than I can remember. I’ve owned shiny, store-bought greenhouses and also built scrappy, home-made shelters with old barn windows and baling twine.
Some of the cheapest ones worked better than the expensive models. If you’ve been itching to extend your season but can’t shell out for a full greenhouse, this guide’s for you.
Below you’ll find 30 greenhouse alternatives that work for farmers and gardeners in the US, UK, and other cooler climates. Some are small, some are big, but all of them can give you the head start or protection you’re after.
A Quick Story From My Own Patch
One spring my tomato seedlings outgrew the windowsill in March. Night frosts were still biting. Instead of panic-buying a kit greenhouse, I bent some leftover irrigation pipe into hoops, threw painter’s plastic over the top, and anchored it with bricks. My “greenhouse” looked like a giant caterpillar, but the plants thrived. That was the year I learned you don’t always need fancy gear to get healthy crops.
The 30 Best Greenhouse Alternatives
Each option below includes a short explanation plus a farmer’s tip to make it work better.
1. Cold Frames
These low boxes with clear lids trap warmth and protect seedlings. I build mine with old windows and 2x4s. Keep a stick handy to prop the lid open on sunny days so your plants don’t cook.
2. Hoop Tunnels
Plastic sheeting over hoops is fast, cheap, and versatile. Push wire or PVC into the ground in arcs and drape heavy plastic over them. Pin down the edges with soil or stones.
3. High Tunnels
The taller version of hoop tunnels. You can walk inside, which makes tending crops easy. Many small farms rely on them for salad greens year-round.
4. Row Covers
Floating row covers protect plants from pests and frost. They’re lightweight, reusable, and roll up small for storage. Great for carrots, lettuce, and brassicas.
5. Polytunnels
Long, semi-permanent structures with tough plastic skin. Very popular in the UK. They’re like greenhouses without the price tag.
6. Cloche Jars
Old school but brilliant. Cover tender seedlings with glass cloches or even cut-off water bottles. They act like mini greenhouses.
7. Shed Conversions
Add clear roofing or south-facing windows to an ordinary shed and you’ve got a plant nursery. Paint the inside white to reflect light.
8. Lean-To Structures
Build a structure against an existing wall. It saves money on materials and uses the wall’s warmth to your advantage.
9. Carport Conversions
Metal carports make great frames. Replace the roof with clear panels or greenhouse film and you’ve got a roomy shelter.
10. Indoor Grow Tents
For folks without outdoor space, a grow tent and LED lights can mimic greenhouse conditions. Ideal for microgreens and herbs.
11. Window Greenhouses
A sunny window plus shelving can function as a small greenhouse. Perfect for flats or urban gardeners.
12. Cold Rooms with Lights
Some farmers set aside an insulated room with grow lights. Not pretty, but it works for seedlings and cuttings.
13. Geodesic Domes
These futuristic domes are efficient and eye-catching. Build with PVC or metal and cover with poly film. They handle wind better than hoop houses.
14. Shade Houses
In hotter regions you need to cool plants, not heat them. Shade houses use mesh to cut sun intensity and keep crops from wilting.
15. Recycled Window Houses
Collect salvaged windows from renovation projects and build a rustic greenhouse. It looks charming and costs next to nothing.
16. Straw Bale Cold Frames
Stack straw bales into a rectangle, place an old door or window on top, and you’ve got a warm, insulated frame for seedlings.
17. Wall-o-Water Cones
Plastic tubes filled with water that surround plants, acting as heat sinks. Slip one over a tomato transplant and watch it take off.
18. Portable Mini Tunnels
Tiny hoop houses you can move from bed to bed. Perfect for succession planting or temporary frost protection.
19. Secondhand Kits
Check online marketplaces for used greenhouse kits. With a bit of cleaning and a few new bolts you can have a greenhouse for half the price.
20. Solar Pit Greenhouses
Also called walipinis. Dig into the ground and cover with glazing. The earth insulates the plants naturally.
21. Pop-Up Greenhouses
Collapsible units that fold up like camping tents. Great for small yards or rented plots.
22. Clear Storage Bins
Flip a clear plastic bin over seed trays to make a mini greenhouse. Vent it on sunny days.
23. Mason Jar Covers
A simple jar over a seedling traps heat and moisture. Works for single plants.
24. Greenhouse-in-a-Box
Pre-fab frames that assemble without tools. Good for those who want something between DIY and full build.
25. Pallet Wall Greenhouses
Stand pallets upright, attach clear panels, and fill the slots with soil or pots. Rustic but effective.
26. Bubble-Wrap Insulation
Line any small frame with bubble wrap for extra warmth. I’ve even used it inside my polytunnel during cold snaps.
27. Balcony Plastic Enclosures
Urban gardeners can wrap balcony railings with clear plastic to create a warm microclimate for pots.
28. Shelving with Covers
Tiered greenhouse racks with zip-up covers protect herbs and small veggies. Easy to move around.
29. Mini Polyculture Domes
Wire and sheeting over mixed plantings create quirky but effective domes. Great for small permaculture beds.
30. Homemade Solar Frames
Put black-painted barrels or large stones inside your plant shelter to absorb daytime heat and release it at night. A cheap, passive heater.
Tips to Get the Most Out of Any Greenhouse Alternative
Pay attention to airflow. Many first-timers forget to vent their structures on sunny days and end up with fried seedlings.
Watch moisture. Dry air stresses plants, but so does standing water. A simple thermometer and humidity gauge can save you a lot of guesswork.
If you’re worried about shedding leaves or debris, most of these setups handle it fine. It’s more about your cleanup routine than the structure itself.
FAQs
Do these alternatives work as well as a real greenhouse?
For certain crops and seasons, yes. Match the setup to your climate and plant needs.
Which option is cheapest?
Row covers, cloche jars, and flipped storage bins cost next to nothing and give surprising results.
Will I need a heater?
Depends on your region. In mild climates, passive solar heat does the job. In harsh winters, a small heater or heat mats may help.
How long do they last?
Plastic covers may need replacing every couple of years. Wooden or window frames can last a decade with care.
Can I combine methods?
Absolutely. I often put row covers inside my hoop tunnel for double protection on frosty nights.
Wrapping It Up
You don’t need a fancy glasshouse to get a jump on the growing season. Whether you’re a backyard gardener or a farmer with a few spare acres, these 30 greenhouse alternatives can keep your crops cozy and thriving. Experiment, mix and match, and don’t be afraid to improvise.
After all, farming and gardening are as much about creativity as they are about hard work. What clever tricks have you used to shelter your plants without a traditional greenhouse?
