Commercial Greenhouse Structures and Solutions for Professional Growers
Sicne 1965, Harnois Greenhouses has been the benchmark for agricultural greenhouses in North America. We design, manufacture, and install durable structures for commercial growers from coast to coast in both Canada &United States), with some projects internationally. We create controlled environment (CEA) optimized for predictability, while taking into account the snow and wind loads specific to our site. Our expertise extends to the vegetable and horticultural sectors, as well as nurseries and garden centers.
Discover our commercial greenhouses structures
Built for commercial growers, each model combines structural strength, light optimization, and disease-reducing design to support higher yields, consistent quality, and long-term profitability.
With more than 60 years of experience and over 10,000 greenhouse installations across North America, Harnois has earned the trust of growers in vegetables, ornamentals, berries, and nursery production. Our four proven greenhouse systems provide the flexibility, performance, and durability required for modern large-scale horticulture; especially in the harshest climates.
Keeping the perfect arch.
The round tube can't. The square one won't. The oval one does.
At Harnois, our exclusive oval tube is not only stronger, it is also more durable. More resistant by design, the oval tube reduces the number of arches, uses less steel, and shortens installation time, saving you time, labor, and materials.
- More durable by nature
- More air, more stability
- Gothic arch = optimal light performance
- Fewer arches, brighter greenhouse
- Extended poly life
+60
years of commercial greenhouse engineering
+10 000
installations worldwide
+10 000
Proudly designed, developed, and manufactured in Quebec – and shipped worldwide.
8 to 15
weeks between consultation and installation.
Building tomorrow's agriculture with comprehensive greenhouse solutions
By rethinking established greenhouse concepts, Harnois develops structures and technologies that meet the evolving demands of commercial agriculture. Our iconic Gothic profiles and proprietary oval-tube framing enhance natural light, reduce disease pressure, and create consistent growing conditions. With innovations like Canada’s first modern glass greenhouse, we combine energy-efficient engineering with sustainability; offering growers more than a structure, but a long-term production solution.
For over six decades, Harnois Greenhouses has been designing, manufacturing, and installing commercial greenhouse structures adapted to the climate realities and production targets of North American growers. As a trusted commercial greenhouse manufacturer, we support horticultural, market-garden, institutional, and research growers with turnkey solutions that deliver long-term performance.
- Nurseries
- Garden centers
- Specialized growers
- Wholesale florists
- Potted plant producers
- Perennial producers
- Annual plant producers
- Landscapers
- Research
- Cities
Ornemental
Ornamental growers don’t just need light, they need control.
Temperature stability, humidity management, and condensation-free growing conditions are what make the difference between a good harvest and an excellent harvest.
Harnois structures are designed with a Gothic arch and an exclusive oval tube to maximize interior air volume, limit condensation buildup, and maintain a stable growing environment.
Our greenhouses offer high suspension capacity, ideal for hanging baskets, planters, and any overhead equipment, without compromising the strength of the structure.
From thermal screens to growing tables, irrigation systems, and climate control, we design complete solutions tailored to your production needs.
- Vegetables
- Fruits
- Specialized Crops
Produce
Commercial growers need more than just a structure: they need a system. From light and height for your plants to the snow load capacity required for Canadian winters. Every detail of a Harnois Greenhouse is designed with your crops and climate in mind. Do you grow tomatoes, cucumbers, peppers, or leafy greens?
Our greenhouse structures are perfectly suited to your ground or suspended vegetable production.
- Nurseries
- Tree Seedlings
- Reforestation
Tree Seedlings
Tree seedling production is a science of density and precision. Millions of seedlings per cycle, watering conditions measured to the millimeter, impeccable air circulation to prevent damping off, every detail counts when your survival rate defines your profitability.
Roll-up side ventilation and roof panels allow for a gradual transition between the controlled greenhouse environment and outdoor conditions, which is essential for hardening seedlings before planting or delivery.
Our structures are designed to support the suspended loads of mechanized irrigation systems, overhead transport rails, and handling equipment, without additional arches that would create shaded areas detrimental to batch uniformity.
- Extension de saison
- Production à l'année
- Fraises
- Framboises
- Bleuets
- Mûres
Soft Fruits
Small fruit growers face a harsh reality: a week of late frost, a week of excessive rain, or a hailstorm can ruin an entire season. With a greenhouse, you regain control.
Extend your season. Protect your harvest. Improve your profitability.
Whether you’re starting out with a few tunnels or managing several acres of intensive production, Harnois offers the right structure for your needs, from large three-season tunnels to glass greenhouses for agro-industrial operations.
Recent Greenhouse Projects across North America
Flowers
Abbotsford Garden Center
Suspended Strawberries
Gadbois Farm
Lettuce
VegPro International
Peppers
Red Sun Fars
Commercial Greenhouse Manufacturer in North America
Family-Owned. Engineering-Driven. Grower-Focused.
Our engineering expertise, personalized approach, and ability to deliver high-performance commercial greenhouses throughout Canada and the United States make Harnois one of the most experienced greenhouse manufacturers in the industry.
