Hoklartherm | Riga Greenhouse Series, Premium German-Made Polycarbonate Greenhouses

The Hoklartherm Riga Greenhouse Series is designed for gardeners who want more than a lightweight seasonal greenhouse. With insulated polycarbonate glazing, a reinforced aluminum frame, and the distinctive curved Gothic shape that Riga is known for, these German-engineered greenhouses provide a durable and practical growing environment for year-round gardening, seed starting, overwintering plants, homesteading, educational programs, and extended-season food production. Whether you are a serious backyard gardener, a homesteader looking for more control over your growing season, a school building a hands-on STEM garden, or a retiree investing in a long-term gardening lifestyle, the Riga Series offers a thoughtful balance of strength, insulation, ventilation, and usable growing space. The Riga S, Riga L, and Riga XL models give gardeners several size options, from compact backyard greenhouses to large-scale growing structures. Each model is built around the same practical idea: protect your plants, extend your season, and create a greenhouse that performs well beyond one growing cycle. SPECIAL ORDERS (XL5, XL7, XL8) Please note that special-order items are not kept in stock, and the estimated lead time is approximately 12 to 16 weeks. KEY FEATURES German-Engineered Performance Built by Hoklartherm in Germany, the Riga Series is known for durable construction, practical ventilation, and strong insulation for serious growing. Excellent for All-Season Gardening Insulated polycarbonate glazing helps support seed starting, season extension, winter plant protection, and year-round growing when paired with the right growing practices. Strong Choice for Homesteaders The Riga Series helps gardeners grow more food, start plants earlier, protect crops longer, and gain more control over seasonal changes. Suitable for Educational Greenhouses Polycarbonate glazing, durable framing, and multiple size options make Riga a practical greenhouse choice for school gardens, STEM programs, and community growing projects. Curved Gothic Shape The rounded profile helps shed snow, reduce wind resistance, and create more usable growing space along the greenhouse sidewalls. Long-Term Gardening Investment For gardeners planning to grow for many years, Riga offers a more substantial greenhouse structure than many entry-level hobby kits. SPECIFICATIONS Riga S2 Greenhouse 7ft x 7ft 8in Dimensions Length: 7ft Width: 7ft 8in Peak Height: 7ft 1in Growing Area: 54 sq. ft. Frame 13-gauge aluminum frame Curved Gothic shape for snow shedding and wind deflection Glazing 8mm twin-wall polycarbonate sidewalls 10mm twin-wall polycarbonate front and back gable panels What’s Included 1 roof vent with auto opener 1 Locking barn-style hinged door 1 rear window Hardware Assembly documentation Riga S3 Greenhouse 10ft 6in x 7ft 8in Dimensions Length: 10ft 6in Width: 7ft 8in Peak Height: 7ft 1in Growing Area: 81 sq. ft. Frame 13-gauge aluminum frame Curved Gothic shape for snow shedding and wind deflection Glazing 8mm twin-wall polycarbonate sidewalls 10mm twin-wall polycarbonate front and back gable panels What’s Included 1 roof vent with auto opener 1 Locking barn-style hinged door 1 rear window Hardware Assembly documentation Riga S4 Greenhouse 14ft x 7ft 8in Dimensions Length: 14ft Width: 7ft 8in Peak Height: 7ft 1in Growing Area: 108 sq. ft. Frame 13-gauge aluminum frame Curved Gothic shape for snow shedding and wind deflection Glazing 8mm twin-wall polycarbonate sidewalls 10mm twin-wall polycarbonate front and back gable panels What’s Included 1 roof vent with auto opener 1 Locking barn-style hinged door 1 rear window Hardware Assembly documentation Riga L3 Greenhouse 10ft 6in x 9ft 8in Dimensions Length: 10ft 6in Width: 9ft 8in Peak Height: 7ft 7in Growing Area: 102 sq. ft. Frame 13-gauge aluminum frame Curved Gothic shape for snow shedding and wind deflection Glazing 8mm twin-wall polycarbonate sidewalls 10mm twin-wall polycarbonate front and back gable panels What’s Included 1 roof vent with auto opener 1 Locking barn-style hinged door 1 rear window Hardware Assembly documentation Riga L4 Greenhouse 14ft x 9ft 8in Dimensions Length: 14ft Width: 9ft 8in Peak Height: 7ft 7in Growing Area: 135 sq. ft. Frame 13-gauge aluminum frame Curved Gothic shape for snow shedding and wind deflection Glazing 8mm twin-wall polycarbonate sidewalls 10mm twin-wall polycarbonate front and back gable panels What’s Included 2 roof vents with auto openers 1 Locking barn-style hinged door 1 rear window Hardware Assembly documentation Riga L5 Greenhouse 17ft 6in x 9ft 8in Dimensions Length: 17ft 6in Width: 9ft 8in Peak Height: 7ft 7in Growing Area: 165 sq. ft. Frame 13-gauge aluminum frame Curved Gothic shape for snow shedding and wind deflection Glazing 8mm twin-wall polycarbonate sidewalls 10mm twin-wall polycarbonate front and back gable panels What’s Included 4 roof vents with auto openers 1 Locking barn-style hinged door 1 rear window Hardware Assembly documentation Riga XL5 Greenhouse 16ft 5in x 14ft Dimensions Length: 16ft 5in Width: 14ft Peak Height: 9ft 10in Growing Area: 231 sq. ft. Frame 13-gauge aluminum frame Large Gothic structure with expanded interior height and width Glazing 16mm triple-wall polycarbonate panels Designed for stronger insulation and serious year-round growing What’s Included 4 roof vents with auto openers 2 Locking barn-style hinged doors Hardware Assembly documentation Riga XL6 Greenhouse 19ft 10in x 14ft Dimensions Length: 19ft 10in Width: 14ft Peak Height: 9ft 10in Growing Area: 280 sq. ft. Frame 13-gauge aluminum frame Large Gothic structure with expanded interior height and width Glazing 16mm triple-wall polycarbonate panels Designed for stronger insulation and serious year-round growing What’s Included 4 roof vents with auto openers 2 Locking barn-style hinged doors Hardware Assembly documentation Riga XL7 Greenhouse 23ft x 14ft Dimensions Length: 23ft Width: 14ft Peak Height: 9ft 10in Growing Area: 322 sq. ft. Frame 13-gauge aluminum frame Large Gothic structure with expanded interior height and width Glazing 16mm triple-wall polycarbonate panels Designed for stronger insulation and serious year-round growing What’s Included 6 roof vents with auto openers 2 Locking barn-style hinged doors Hardware Assembly documentation Riga XL8 Greenhouse 26ft 3in x 14ft Dimensions Length: 26ft 3in Width: 14ft Peak Height: 9ft 10in Growing Area: 368 sq. ft. Frame 13-gauge aluminum frame Large Gothic structure with expanded interior height and width Glazing 16mm triple-wall polycarbonate panels Designed for stronger insulation and serious year-round growing What’s Included 6 roof vents with auto openers 2 Locking barn-style hinged doors Hardware Assembly documentation Riga XL9 Greenhouse 29ft 6in x 14ft Dimensions Length: 29ft 6in Width: 14ft Peak Height: 9ft 10in Growing Area: 413 sq. ft. Frame 13-gauge aluminum frame Large Gothic structure with expanded interior height and width Glazing 16mm triple-wall polycarbonate panels Designed for stronger insulation and serious year-round growing What’s Included 8 roof vents with auto openers 2 Locking barn-style hinged doors Hardware Assembly documentation WHAT'S INCLUDED Each Riga greenhouse includes the aluminum frame, polycarbonate glazing panels, barn-style hinged locking door system, roof vents, automatic roof vent openers, required hardware, and manufacturer assembly documentation. Riga S and Riga L models also include a rear window for additional natural ventilation. Riga XL models include two locking barn-style doors and multiple automatic roof vents depending on model size. INSTALLATION GUIDE Riga greenhouses should be installed on a level, secure foundation. Proper anchoring is important for long-term structural performance, especially in areas with wind, snow, or shifting soil conditions. Common installation options include a concrete strip foundation or the optional Riga foundation base. Always review the manufacturer assembly manual before beginning installation and check local permit requirements before ordering. Riga Greenhouse Installation Guide PRODUCT VIDEO RIGA GREENHOUSE INSTALLATION VIDEO MAINTENANCE AND CARE Clean the Polycarbonate Panels Use mild soap and water as needed. Avoid abrasive cleaners that may scratch or damage the glazing surface. Inspect Roof Vents Check automatic openers seasonally to make sure the vents open and close smoothly as temperatures change. Monitor Snow Accumulation The curved shape helps snow slide off, but heavy snow buildup should still be monitored and cleared when necessary. Check Anchoring Inspect the greenhouse foundation and anchors after severe weather or seasonal ground movement. OPTIONAL ACCESSORIES Available Riga accessories may include foundation bases, drop door kits, additional roof vents, vent openers, roof vent restraint cable systems, sash locks, top shelves, bottom shelves, seed trays, exhaust fans, solar-powered exhaust fans, intake vents, greenhouse heaters, digital thermostats, plant hooks, misting systems, solar lights, grow lights, wheelbarrow ramps, and T-bolts. Accessory bundles may also be available for select Riga and Riga XL models, including shelving and foundation frame packages. Warranty Polycarbonate: 15 Year Limited Warranty (prorated after 5 years) Frame: 15 Year Limited Warranty MANUFACTURER INFO AND UNIQUE SELLING POSITION Hoklartherm is a German greenhouse manufacturer known for producing high-quality greenhouses, conservatories, pavilions, patio roofs, and solar verandas. The Riga Series reflects Hoklartherm’s focus on strong aluminum profile systems, insulated glazing, practical airflow, and long-term structural performance. The Riga Series stands out because it is built for gardeners who want dependable growing performance instead of a short-term seasonal structure. Its curved Gothic shape, insulated polycarbonate panels, heavy-duty aluminum frame, and automatic ventilation make it a strong fit for serious gardeners, homesteaders, educators, and all-season growers. Riga greenhouses are also well suited for educational and community growing programs. The insulated polycarbonate glazing provides a safer and more forgiving learning environment than traditional glass, while the different size options allow schools, garden clubs, and community organizations to choose a greenhouse that fits their space, budget, and teaching goals. For many homeowners, the Riga Series is also a long-term investment in a more productive and enjoyable gardening lifestyle. It can support food production, plant protection, seed starting, tropical plant overwintering, and quiet year-round time in the garden. FREQUENTLY ASKED QUESTIONS Is the Riga greenhouse suitable for year-round growing? Yes. The Riga Series is well suited for extended-season and year-round growing in many climates when paired with proper ventilation, heating, shading, and growing practices. The insulated polycarbonate glazing helps retain heat better than thin single-layer coverings. Is the Riga greenhouse a good choice for homesteaders? Yes. Riga greenhouses are a strong fit for homesteaders who want to start seeds earlier, protect crops longer, overwinter plants, and improve food-growing reliability through changing seasons. Can the Riga greenhouse be used as an educational greenhouse? Yes. The Riga Series is a practical option for school gardens, STEM programs, community gardens, and hands-on growing education. The polycarbonate glazing is more impact-resistant than glass, and the insulated design helps create a more stable growing environment for learning. Which Riga model is best for a small backyard? The Riga “S” models are best for smaller spaces because they provide strong insulation and durable construction in a more compact footprint. They are a good choice for suburban gardens, smaller yards, and gardeners who want serious performance without choosing a large greenhouse. Which Riga model is best for serious all-season growing? The Riga XL models are best for serious all-season growing because they offer more interior space, taller height, two doors, multiple automatic roof vents, and 16mm triple-wall polycarbonate glazing for stronger insulation. Is Riga a good greenhouse for retirees or long-term homeowners? Yes. Many long-term homeowners choose Riga because it is designed as a durable, practical greenhouse investment. It supports productive gardening, plant protection, and a more enjoyable year-round gardening lifestyle. Can Riga greenhouse be extended for future growth? No, there is no extention kit for Riga. Since they cannot be extended, we recommend that you buy one size bigger than you planned.