The 7 Best Greenhouses of 2021

Extend your growing season—or better yet, garden all year—with a greenhouse

Our editors independently research, test, and recommend the best products; you can learn more about our review process here. We may receive commissions on purchases made from our chosen links.

Your growing season doesn’t have to end at with first cold days of fall. When you add a greenhouse to your indoor or outdoor space, you can extend your garden by months. In some areas, you might even be able to garden year-round. You don't need a huge space or a lot of money to have your own greenhouse, because there are so many options on the market.

As you start your search for a greenhouse, the first thing you’ll want to consider is your space. No matter the size you have to work with, the lighting and location will both have a huge say in what kind of setup you need. This will also help you know what other equipment or supplies you’ll need in order to be successful. If you’re particularly handy, you might consider building your own. For instance, this geothermal greenhouse has been extremely popular over the years, and the builder did it for less than $300! You can also look into the walipini option or a hoop house.

Whether you decide to build on your own or buy something to get you started, you’re going to love having a greenhouse. Not only will it lighten those darker months, but you’ll have bright plants and maybe even delicious food to enjoy, too. It shouldn’t be hard to find the perfect one to meet your needs, we hope this list helps you find the right greenhouse for you.

Here are Treehugger's picks for the best greenhouses:

The Rundown
This mini greenhouse is perfect for seed starting or protecting some tender veggies in a small corner of your garden or balcony.
You can dip your toe into the greenhouse world with this easy, cost-effective choice.
This large structure goes up quick and easy, because you don’t need any tools for assembly.
Best For Small Spaces:
Mini Pop Greenhouse at Amazon
You’ll only need about a 3-foot square space for this miniature greenhouse.
Build your own greenhouse with these plans, which include a materials list, cut list, and drawings.
This cold frame is of the most durable, reliable, and easy-to-use on the market today.
This recommendation is not greenhouse, but it’ll help get you started on the perfect indoor set-up.

Best Overall: Lukio 3.34' W x 2.09' D Cold Frame

Lukio 3.34' W x 2.09' D Cold Frame

This mini greenhouse is perfect for seed starting or protecting some tender veggies in a small corner of your garden or balcony. The frame is made from reclaimed wood, which holds translucent polycarbonate panels. It's also Greenguard certified, which ensures the greenhouse won't offgas.

It measures 1.25 H x 3.34 W x 2.09 D inches, and weighs 9.7 pounds. On warmer days, you can open the hinged roof panel for ventilation, and keep it in place with handy bolts. It’s a sturdy little greenhouse, which requires no tools for assembly. 

Best Budget: OGrow Mini Greenhouse

OGrow Mini Greenhouse

Thinking about trying a greenhouse but not ready to invest a lot of time, space, or money? This greenhouse made by Amerlife is a great choice for starters. You can use it both inside or out—the ground pegs will help stake it and hold it in place.

Many people use portable greenhouses like this one to cover fragile plants in winter, or to get an early start on seeds in spring. Depending on your area's climate, you can even use a greenhouse to keep your favorite veggies growing throughout the year. The Amerlife Portable Greenhouse is an easy, cost-effective way to dip your toe in the greenhouse world.

Best Portable: KOKSRY Indoor and Outdoor Greenhouse

The pipe frame of this house is made from steel, while the structure itself uses environment-friendly polyethylene (PE)—a material that is resistant to cold temps. KOKSRY's greenhouse is one of the most affordable options for its large size, sitting at 56 inches wide x 30 inches deep x 76 inches tall.

It should go up quick and easy, because you don’t need any tools for assembly. It's easy to move it around to anywhere in your home or yard. This greenhouse can be used to overwinter plants, grow new ones, or for seedlings. It’s even roomy enough to do all three!

Best For Small Spaces: Mini Pop Greenhouse

You only need about a 3-foot square space for the Mini Pop Greenhouse. Installation only takes seconds because all you have to do is pop it up, and it’s ready to go. It comes with four steel ground tacks if you want to secure it to a garden bed, and features a zippered window that can be opened during warmer days and closed at night.

This greenhouse works well for that tender plant that needs extra protection in winter, or you can grow something completely new. When you’re done using this greenhouse for the season, it folds flat for easy storage. This is perfect both inside or out, all you need is a sunny spot.

Best Plans to DIY: Rob Terry 8' x 12' Greenhouse Plans

RJ Terry 8' x 12' Greenhouse Plans

The owner of this Etsy store, Rob Terry, really covers the market when it comes to greenhouse plans. He has a few dozen to choose from, ranging in size, and his plans make it so easy to understand the necessary steps and put it all together.

The plans for this 8 foot x 12 foot greenhouse come with a spiral, 47-page book that includes a materials list, cut list, and drawing to help illustrate every step along the way. His goal is to make it possible for anyone to make their own greenhouse with basic supplies (this one mostly calls for 2x4 boards). 

Best Cold Frame: Exaco Trading Biostar 1500 Cold Frame

Biostar 1500 Cold Frame

This cold frame is designed to withstand up to 6 feet of snow with extra insulation, so it’s truly an option for any climate. Each of the three separate windows can be opened individually for ventilation, and one has an automated opener. The unit measures 50 x 23 x 16 inches, and the transparent panels are UV-resistant so they shouldn't yellow.

It breaks down to store flat, so you can easily put it away when you don't need it. Assembly does require some drilling.

Best for Indoors: Aokrean Grow Lights for Indoor Plants

This recommendation is not greenhouse, but it’ll help get you started on the perfect indoor set-up.

The Aokrean Grow Light has four LED arms that are easy to move around, and an adjustable tripod. The flexibly of this light be used in a number of different ways, for example inside a pop-up greenhouse or in an extra space or any room in your house. With enough lights, you could even create a greenhouse in your basement. These lights have a timer option and are dimmable, giving you even more control to adjust it to your specific space or needs.

Final Verdict

Our top pick is the Lukio Mini Greenhouse (view on Wayfair), made from reclaimed wood. If you’re looking for a big greenhouse to protect lots of plants, we suggest the KOKSRY Indoor and Outdoor Greenhouse (view on Amazon).

Why Trust Treehugger?

We strive to help our readers find the right tools to grow local food at home. Author Stacy Tornio is a licensed Master Gardener, and has written over 15 books about nature, gardening and the great outdoors.