The Best Deep Winter Greenhouse for Sale

In the realm of sustainable agriculture, finding efficient ways to grow food year-round in cold climates is a challenge. Enter the deep winter greenhouse—a beacon of hope. A deep winter greenhouse is specifically designed for cold climates, utilizing advanced architectural and technological features to maintain a warm, sustainable environment for plant growth even during the harshest winter months.

These specialized structures are engineered to capture and retain heat, provide adequate light, and protect plants from extreme cold, often relying on passive solar energy and efficient insulation to create a viable microclimate for year-round cultivation. Key elements in a deep winter greenhouse include high-quality insulation, optimal solar heat gain, efficient thermal mass, durable glazing material, effective ventilation systems, and more.

The Growing Dome® from Growing Spaces is a prime example of a deep winter greenhouse that not only meets but exceeds these criteria. Its unique geodesic shape, combined with state-of-the-art features, makes it a top choice for those seeking to garden all year. Even into the depths of winter. Let’s delve into how the Growing Dome expertly aligns with each essential feature of a deep winter greenhouse.

High-Quality Insulation

Ensuring a cozy and warm environment inside your greenhouse during the frosty months is crucial. That’s where the Growing Dome’s exceptional insulation comes into play. Here are a few ways they keep the chill out:

• Multi-wall Polycarbonate Glazing: The Growing Dome features a special 16mm, multi-wall polycarbonate glazing. With an R-value of 2.8, it’s like wrapping your greenhouse in a warm blanket, keeping the warmth in and the cold out.
• Insulated Foundation Wall: Beneath the beauty of our greenhouse lies a practical secret—2-foot foam board insulation within the foundation wall. This smart feature ensures that the soil in your growing beds retains heat, even on those cold winter nights. Plus, each kit comes with spray foam to seal any gaps, ensuring every nook and cranny is snug and warm.
• Double Insulation on the North Side: The north side of the Growing Dome gets special treatment with reflective insulation. Covering about a third of the inner polycarbonate panels, this material works year-round. It keeps the dome warm in winter and cool in summer, especially above the pond area—but more on that later.

Optimal Solar Heat Gain

A deep winter greenhouse design should maximize sunlight absorption. The Growing Dome is designed to make the most of natural sunlight, providing your plants with a balanced and nourishing environment from dawn to dusk.

• The Curve Advantage: Unlike a typical rectangular greenhouse, the Growing Dome boasts a curved surface. This isn’t just for looks—it plays a crucial role in heating. Throughout the day, this curved shape ensures an even distribution of sunlight and warmth inside the dome. It’s like having a personal sun tracker for your greenhouse!
• Sunlight All Day Long: With a rectangular greenhouse, you get a burst of sunlight at midday when the sun is directly overhead, but what about the mornings and late afternoons? That’s where the Growing Dome has an edge. Its design allows for consistent and beneficial sun exposure, right from the early morning to the late afternoon. This means no more negligible light input when the sun is low in the sky—your dome captures every precious ray.

We think it is important to note that while hoop houses can capture sunlight more effectively than English-style greenhouses, they don’t provide the same level of solar absorption as geodesic domes.

Efficient Thermal Mass for a Deep Winter Greenhouse

In the world of greenhouses, thermal mass is a game-changer, and water is one of its best forms because of its ability to efficiently store and release heat. The Growing Dome smartly incorporates this principle with a feature that’s both functional and visually appealing—the Above Ground Pond.

• Perfectly Sized for Each Dome: These ponds aren’t just afterthoughts; they are meticulously sized and integrated into each Growing Dome. The size of the pond is carefully calculated based on the dimensions of the dome, ensuring optimal thermal regulation.
• Winter Warmth and Summer Cool: The pond plays a dual role. During the chilly winter months, it absorbs heat from the sun and releases it slowly, keeping the dome warm when the temperatures outside drop. In the summer, it acts as a natural cooling system, regulating the internal temperature and preventing the dome from overheating.

Durable Glazing Material

High-quality glazing allows maximum light penetration while minimizing heat loss. The Growing Dome greenhouse kit uses premium 5-Wall (16mm thick) polycarbonate glazing. It is 100% recyclable, has a 10 year prorated warranty, and performs well in extreme weather like wind, hail, and snow.

Effective Ventilation System

In any greenhouse, good air flow isn’t just a luxury – it’s a necessity.

• Automatic Greenhouse Vents: Imagine vents that open and close on their own, without needing any power! That’s exactly what the Growing Dome offers. These smart vents are heat-activated, relying on a beeswax solution that expands and contracts with temperature changes. No electricity, no manual labor, just pure, clever design

• The “Chimney” Effect for Cooling: Here’s how it works – as the air inside the dome heats up, it rises and escapes through the upper vents. This creates a vacuum that draws cooler air in through the lower vents. It’s like a natural air conditioning system, preventing overheating and ensuring a constant flow of fresh air, crucial for preventing plant diseases and maintaining a comfortable temperature.
• Solar and Electric Fans: Our 33’ and 42’ greenhouse kits come standard with electric fans, and the 15′, 18′, 22′, and 26’ Growing Dome kits come with a solar-powered fan. An extra solar-powered fan can be added as an upgrade to any Growing Dome® greenhouse kit. If you choose the solar-powered upgrade for the 42′ Growing Dome, you receive four 12v solar-powered fans to replace the three 115V fans.

Snow Load Capacity for a Deep Winter Greenhouse

When the snow starts piling up, you want to know your greenhouse can handle it. That’s where the Growing Dome’s smart design really shines. Built to withstand heavy snow loads, it’s a winter warrior in the world of greenhouses.

• Geodesic Design—Snow’s Worst Enemy: The dome’s round shape isn’t just for show; it’s a strategic feature against snow accumulation. As snow falls, the dome’s curvature encourages it to slide off naturally. This means less build-up and less stress on your greenhouse structure.
• Strength in Triangles: At the heart of the Growing Dome’s resilience is its geodesic structure, made up of numerous triangles. Why triangles? Because they’re incredibly strong and rigid, making the dome not just beautiful, but also immensely sturdy.
• Rated for Heavyweights: Officially, the Growing Dome is rated for 225 pounds per square inch (psi) of snow load. That’s a lot of snow! But the best part? If you live in an area with exceptionally heavy snowfall, the dome can be modified to handle even higher loads.

Energy-efficient Heating Systems

In case additional heating is needed, it should be energy-efficient. While the Growing Dome’s design reduces the need for extra heating, any supplemental systems are designed to be energy-efficient.

Heat loss from any structure is proportional to the surface area of the structure. A spherical shape has the minimum surface area for the amount of floor space enclosed. The Growing Dome is much more effective at keeping the heat in on a cold winter night simply by having 40% less surface area than a rectangular structure through which the heat can escape.

Every Growing Dome Greenhouse comes standard with a geothermal climate control system that we call the undersoil ventilation system.

Internal Layout and Space Utilization

Efficient space use is key. The great part about the Growing Dome is that the design of the inside is completely up to you. You can do raised bed gardening, hanging planters, and even floating water plants in the above-ground pond. Because the greenhouse is dome shaped the center areas of the greenhouse offer ample height to grow various fruit trees. Because the Growing Dome comes in 6 different sizes you can choose the size that best fits you for growing but some people opt to size up to enjoy both ample gardening space and room for relaxation like a table and chairs or couch.

Integrated Water Management Systems

The standout feature is the use of water from the above-ground pond, suitable for either drip irrigation or hand watering. This method is especially beneficial for those with fish in their pond, as the fish waste naturally enriches the water with nitrogen, fostering healthier plant growth and reducing the need for artificial fertilizers.

Here at Growing Spaces, we offer a solar-powered irrigation system that comes with everything needed to set it up including 155’ of distribution hose and 50 nozzles. If you are going to irrigate directly from your pond, make sure that you have a filter or a filter bag covering the pump to prevent clogs.

Durability and Low Maintenance Needs

Growing Domes are not only built to withstand harsh weather they are also proven to withstand the test of time. Many of our gardeners have been growing in their greenhouses for decades with proper maintenance!

All of our greenhouse kits come with access to detailed preventive maintenance instructions, schedules, and part replacement instructions.

Deep Winter Greenhouse Cost-Effectiveness

Considering initial investment against long-term savings. Growing Domes, though an investment upfront, offer significant long-term savings due to their lower heating costs and long term durability.

Using the information obtained from past customers, Growing Spaces created a Return on Investment calculator for every size dome! We must admit gardening is not easy, and not everyone has green thumbs and toes. There will be years where you produce more or less. For that reason, we kept the calculator very modest, but you can adjust based on the size of Growing Dome you are interested in, your expected yields, and your current organic food budget.

Adaptability to Local Climate Conditions

A deep winter greenhouse should suit your specific winter conditions. Over the years, as the Growing Dome’s reach has extended to all 50 states and 14 countries worldwide, we’ve developed some components and guidance for customers who live where it may be cloudier, more humid, much colder, or even hotter than the Rocky Mountain West.

In addition to choosing options for your climate you can also choose options for the climate you wish to create on the interior. Maybe you want to grow tropicals in Canada? We can help you.

To learn about building the perfect greenhouse kit of your climate please read our article Choosing Growing Dome Options and Upgrades for your Region!

The Growing Dome vs Other Deep Winter Greenhouses

If you’ve read this far, you might still be weighing other deep winter greenhouse options. Let us make a final case for the Growing Dome. You’re already familiar with the innovative technology behind the Growing Dome, but it’s essential to understand that no greenhouse offers a perfect, effortless solution to winter gardening. What sets Growing Spaces apart isn’t just the greenhouse; it’s the community you join when you purchase from us.

As a small, family-owned business with over 30 years of experience, we don’t just build greenhouses; we grow in them too. Our commitment to your success extends far beyond the purchase and assembly of your greenhouse. We believe in ongoing support, whether it’s through gardening tips in our monthly newsletter and YouTube videos or the community interactions in our Facebook groups. When you choose a Growing Dome, you’re not just buying a structure; you’re gaining access to a wealth of knowledge and a community of like-minded gardeners who want to see you succeed.

Deep Winter Greenhouse Frequently Asked Questions (FAQs)

What are the best crops to grow in a deep winter greenhouse?

The best time to start your winter growing season is in late August or early September, but we have had success with fast-growing crops as late as October. You can find a full list of our suggested winter crops on our winter gardening page.

What type of greenhouse is best for winter?

The best type of greenhouse for winter is one that has excellent insulation, efficient solar heat gain, and can withstand heavy snow loads. Geodesic dome greenhouses, like the Growing Dome, are often considered ideal due to their structural strength and energy efficiency.

Will an unheated greenhouse keep plants from freezing?

An unheated greenhouse can keep plants from freezing, especially if it’s well-insulated and designed to maximize solar heat gain. However, in extremely cold climates, some supplemental heating might be necessary.

Is it cheaper to build a deep winter greenhouse or buy one?

The cost-effectiveness of building vs. buying a greenhouse depends on various factors like materials, size, and design complexity. Prefabricated greenhouse kits like the Growing Dome offer value through optimized design and durability, which can be more cost-effective in the long run compared to a DIY greenhouse.

Are unheated greenhouses worth it?

Yes, unheated greenhouses can be worth it, especially for extending the growing season in the spring and fall. In milder winter climates, they can also be effective for winter gardening.

Do I need to vent the greenhouse in winter?

Yes, ventilating the greenhouse in winter is important to manage humidity levels and prevent condensation, which can lead to mold and encourage pesky pests.

How warm can a greenhouse stay in winter?

The internal temperature of a greenhouse in winter can vary depending on its design, insulation, and exposure to sunlight. Well-designed greenhouses like the Growing Dome can maintain a temperature significantly warmer than the outside environment, even without additional heating.

Can I grow plants all year round in a greenhouse?

Yes, with the right greenhouse design and conditions, it is possible to grow plants all year round. This includes cold-hardy varieties in the winter and a broader range in warmer months.

How can I heat my greenhouse without electricity?

To heat a greenhouse without electricity, you can use passive solar techniques, thermal mass (like water barrels or stone walls), compost heating, propane, or solar-powered heaters.

What maintenance does a greenhouse require in winter?

Winter greenhouse maintenance includes regular checks for structural integrity (especially after heavy snowfall), ensuring proper ventilation, monitoring temperature and humidity levels, and keeping the glazing clear for maximum light exposure. Fortunately, the geodesic shape of a Growing Dome allows the snow to slide right off.

Can I use a greenhouse to grow exotic plants in winter?

Yes, a well-insulated and heated greenhouse can create a microclimate suitable for growing exotic plants even in winter. The key is to maintain the appropriate temperature and humidity levels for the specific plants you wish to grow.

How do you build a deep winter greenhouse?

We can’t speak on behalf of all deep winter greenhouse kits but the Growing Dome has three different options for installation—self-installation, full crew installation, and supervisor installation.