Top greenhouse ideas 

In most parts of the world, gardening is an activity for spring, summer and fall — but a well-designed greenhouse can give you four seasons of growing.

The keys to keeping your greenhouse healthy are heat, insulation, heat retention and light. While creating a healthy environment for crops can be intimidating, there are many affordable and easy ways to produce a healthy harvest through winter and get a jump on spring planting. And no matter the size of your greenhouse, there are many accessories to help your plants flourish.

Best winter greenhouses

If you don’t already have one, choosing a greenhouse designed for year-round growing is a crucial first step. 

Top winter greenhouse

Best King Canopy 10-By-10-Foot Greenhouse

King Canopy Greenhouse

What you need to know: While it’s not much to look at, this simple, spacious greenhouse can withstand a few inches of snow.

What you’ll love: The sturdy, powder-coated steel frame holds up to wind, and at 10 feet by 10 feet, this is large for the price.

What you should consider: Putting the tarp over the frame can be challenging, and the opaque plastic doesn’t let a lot of light through.

Where to buy: Sold by Home Depot

Top winter greenhouse for the money

Best Gardman 4-Tier Mini Greenhouse

Gardman 4-Tier Mini Greenhouse

What you need to know: For indoor winter gardening, this is affordable and space-efficient. Just make sure you have a south-facing window nearby.

What you’ll love: Metal shelves come built-in, so all you really need are some pots and possibly some grow lights.

What you should consider: This is an indoor-only choice.

Where to buy: Sold by Home Depot

Best ways to heat a greenhouse

Your greenhouse should passively keep itself warm in the winter, but sometimes sunlight and insulation aren’t enough for extreme temperatures. That’s where a heater becomes a vital tool in four-season gardening.

Top way to heat a greenhouse

Best Biogreen Basic Electric Fan Heater

Biogreen Basic Electric Fan Heater

What you need to know: This 1,500-watt heater can easily keep most greenhouses warm during the coldest months. 

What you’ll love: The IPX4 rating means this little heater can withstand the humidity of your greenhouse, but it  can be used elsewhere in your home, too.

What you should consider: For greenhouses larger than 120 square feet, this model probably won’t be sufficient.

Where to buy: Sold by Amazon

Top way to heat a greenhouse for the money

Best Calm Life Unscented Soy Tea Light Candles

Calm Life Unscented Soy Tea Light Candles 

What you need to know: By propping a spare terra-cotta pot on some bricks and lighting these candles under it, you can heat a small space at an extremely low price.

What you’ll love: If you live in a generally warm region that occasionally has cold winter nights, this is simple, costs very little and can keep your plants safe from frost.

What you should consider: It’s best to use this system only when you can keep an eye on it. Light the candles when you’re working in your greenhouse, or when you’re nearby to keep watch, just as you would with normal candles.

Where to buy: Sold by Amazon

Best greenhouse insulation

To reduce the amount of time you need to run a heater, invest in good insulation to keep that precious heat trapped, even at night.

Top greenhouse insulation

Best Duck Brand Bubble Wrap

Duck Brand Bubble Wrap

What you need to know: This common material acts as excellent insulation with its translucency and air pockets to trap heat.

What you’ll love: Insulating your greenhouse with bubble wrap is as simple as attaching it to the walls and ceiling for winter-ready protection. 

What you should consider: You will most likely have to replace the bubble wrap after a season or two.

Where to buy: Sold by Amazon

Top greenhouse insulation for the money

Best Aviditi Corrugated Cardboard Sheets

Aviditi Corrugated Cardboard Sheets

What you need to know: Strategically placing cardboard along the bottoms of the walls in your greenhouse can keep cold from seeping in. 

What you’ll love: It will take you under an hour to insulate your greenhouse with cardboard, and once it’s in place, it will probably be mostly hidden by your shelves.

What you should consider: Moisture will inevitably damage any cardboard used for insulation by the end of the season, but you can just chuck it in your compost pile.

Where to buy: Sold by Amazon

Best heat retention ideas

Combining your heat system and insulation with materials that retain heat, such as stone or water, lets your greenhouse stay warm day and night.

Top heat retention idea

Best Granite Cobble Paving Stones

Granite Cobble Paving Stones

What you need to know: Laying a floor of stones collects heat from the ground and from sunlight during the day. 

What you’ll love: This most basic heat retention system also serves as attractive flooring.

What you should consider: These granite cobbles are expensive as stone pavers go, and it will take some time and careful planning to lay them properly.

Where to buy: Sold by Wayfair

Top heat retention idea for the money

Best Mountain View 1 Gallon Plastic Jugs

Mountain View 1-Gallon Plastic Jugs

What you need to know: Believe it or not, water retains heat well in cold environments. If you paint these jugs black, they attract heat in the day time and radiate heat at night.

What you’ll love: Using plastic jugs to warm your greenhouse is as simple as filling them with water, painting them black and placing them in your greenhouse, where they will catch sunlight and warm up in the daytime. 

What you should consider: While this will keep your greenhouse fairly warm, you may need to add some form of insulation.

Where to buy: Sold by Amazon

Top greenhouse grow lights

If you live far from the equator, winter days may be quite short. That’s where grow lights can come in handy to give your plants as much light as they need.

Top greenhouse light

Best Spider Farmer SF4000 LED Grow Light

Spider Farmer SF4000 LED Grow Light

What you need to know: If gardening is a source of income for you, this commercial-grade grow light can support several plants.

What you’ll love: This energy-efficient choice shines brightly — and because it can run hot, you get the added bonus of extra heat.

What you should consider: The price tag may put this light out of reach for hobby gardeners, and it may take years to pay for itself. 

Where to buy: Sold by Amazon

Top greenhouse light for the money

Best Roleadro LED Grow Light

Roleadro LED Grow Light

What you need to know: This full-spectrum light uses only 75 watts while offering enough light for smaller gardens.

What you’ll love: The price of this hanging LED array combined with its energy efficiency means you can light your greenhouse all winter at a very low cost.

What you should consider: The lights are on the dimmer side.

Where to buy: Sold by Amazon

 

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Peter McGuthrie writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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