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Hoklartherm Riga 5 Greenhouse 10x18

Hoklartherm Riga 5 Greenhouse 10x18

4.9/5 · 147 verified reviews

A German-engineered, insulated greenhouse for serious gardeners who want fresh harvests all winter long.

Regular price $11,699.00 USD
Regular price Sale price $11,699.00 USD
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  • AUTHORIZED RETAILER
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  • NO SALES TAX
  • PRICE MATCH GUARANTEE
  • GREAT TECHNICAL SUPPORT
FRAME COLOR
Accessory Kit
Foundation Frame (Base)
★★★★★
“Greenhouse quality is superb and the customer service is outstanding. Thank you to Mulberry Greenhouses!”
Tea C. · Verified buyer Read all 147 reviews →
  • Year-round growing with 8 mm twin-wall polycarbonate and 10 mm end walls
  • Heavy-duty aluminum frame with permanently joined profiles
  • Rounded onion-shaped roof sheds snow and stands up to wind
  • 4 automatic roof windows plus an oversized rear window
  • 165 sq ft of floor space with 7' 6" center headroom
  • Engineered and made in Germany by Hoklartherm
  • 100% free shipping
  • Authorized retailer
  • No sales tax (except georgia)
  • Price match guarantee
Questions before you buy? Talk to a greenhouse specialist: 678-408-8222 or Info@mulberrygreenhouses.com
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Product Description

divider-leaf-green

Hoklartherm Riga 5 Greenhouse 10 x 18 x 8

The Riga 5 insulated greenhouse is engineered for true year-round growing, with first-class insulation that supports fresh vegetables, herbs, and flowers even in the middle of winter. Its heavy-duty aluminum frame, German-made twin-wall polycarbonate glazing, and onion-shaped profile provide excellent strength, wind resistance, and snow shedding in cold climates. Automatic roof and rear windows, a barn-style locking door, and generous interior height create a durable, easy-to-use space for serious gardeners.

As the Germans like to call it the "Onion" shaped, this structure withstands strong winds. Riga is the best structure for cold weather especially during snows. Snow will slide right off . The frame is really strong which explains why our customers always brag about keeping these greenhouses for a long time!

One major advantage of the Riga's construction method is that the frame profiles are permanently attached to each other, and won't come loose over time due to wind pressures.

The poly-carbonate glazing on the Riga Greenhouse is German made and believed to be of superior quality than the much more common Poly-gal or GE glazing.

In addition, great airflow is provided as you open the Dutch barn style door. As the temperature of the greenhouse changes, the over-sized rear window will open and close automatically depending on the inside temperature.

Specifications and Benefits of the Riga 5 Greenhouse:

    • ✔ Extremely heavy duty construction, great for windy areas or for snow season. Similar class to Volkswagen/Volvo, very dependable.
    • ✔ Frame made of Aluminum.
    • ✔ 8 mm UV coated twin-wall Poly-carbonate over main body.
    • ✔ 10 mm twin wall poly-carbonate in front & back walls for extra strength
    • ✔ Comes with DVD and written Assembly Instructions

Technical Information:

✔ One wide, Heavy duty Dutch Barn Door with keyed lock - 30 in wide x 79 in tall.

✔ Over-sized Rear Wall window: 30" wide x 72" high with adjustment arm

✔ First-class insulation: R or K-value 3.0

✔ 4 Roof Window(s): 40" w x 24" d; with Automatic Window Opener

✔ Floor Space: 165 sq. ft. (9' 8" wide x 17' 6" long)

✔ Inside walking height: 6 ft 1 in near shelves, 6 ft 11 in in the middle

✔ Size: 9'8" W X 17'6" L X 7'7" H

✔ Assembly time: 2 people, 1 full day (3 makes it easier and reduces it to 6-8 hours (excluding any shelves)

✔ Warranty: Poly-carbonate: 10 years; Frame: 15 years

NB: We recommend you buy one size bigger than you planned.

The RIGA Greenhouse is designed, engineered, and manufactured in Germany by Hoklartherm, a leading manufacturer of commercial and hobby greenhouses, and other structures, with over 28 years experience.

Riga 5 Greenhouse Accessory Kit

The Accessory Kit bundles the three most popular Riga add-ons at a discount. It includes:

  • ✔ Foundation frame: highly recommended. It attaches to the bottom of the greenhouse and anchors it in a 6" deep trench, so you don't need a concrete slab.
  • ✔ Top shelf, 10" wide x about 17 ft long: attaches to the greenhouse side.
  • ✔ Bottom shelf, 25" wide x about 17 ft long: hangs from the roof for extra stability and space.

The shelves are made of removable twin-wall polycarbonate panels, so light reaches the plants below and you can lift out sections to make room for taller plants.

What's in the Riga greenhouse accessory kit: foundation frame, 10 inch top shelf and 25 inch bottom shelf

Important Shipping & Delivery Information 🚚

  • 🌿Curbside Delivery
  • 🌿Delivery is done through LTL Motor Freight and is free, unless you live in an area with limited access (i.e. island etc...this is extremely rare) this might incur extra fees.
  • 🌿We ship using an 18 wheeler (let us know if there are tight roads or low hanging wires, manufacturer cannot guarantee the availability of a smaller truck)
  • 🌿Someone will need to be available to receive the greenhouse. We will call to set up a delivery timeframe. Driver might need help although he will do most of the work.

Technical Documents:

📝 Assembly and Foundation document
📝 Assembly Video
📝 Structural Certification: Wind and Snow load
📝 Product Warranty
  • 165 sq ft Floor area
  • 9' 8" W x 17' 6" L x 7' 7" H Exterior size
  • Heavy-duty aluminum, black or silver Frame
  • 8 mm twin-wall polycarbonate, UV coated (10 mm end walls) Glazing
  • R/K-value 3.0 Insulation
  • 15 yrs frame, 10 yrs glazing Warranty

Exaco · Hobby Greenhouse

Overview

The Riga 5 is a true four-season greenhouse by European standards. Its 8 mm twin-wall polycarbonate, with 10 mm panels on the front and back walls, gives it the insulation you need to grow fresh vegetables, herbs and flowers in the middle of winter. Greenhouses with thinner panels are really season extenders: they shelter established plants from a light frost but cost too much to heat through a real winter.

Hoklartherm's signature onion-shaped profile lets snow slide straight off and holds up in strong winds. The aluminum frame profiles are permanently joined to each other, so they won't work loose over the years, which is why Riga owners keep their greenhouses for so long. The German-made polycarbonate is a step above the more common glazing brands.

Ventilation takes care of itself: four roof windows open and close automatically with the temperature, the oversized rear window adds cross-breeze, and the Dutch barn door opens top and bottom.

Our tip: Riga greenhouses can't be extended later, so choose one size larger than you think you need.

Hoklartherm Riga 5 greenhouse with a black frame and double doors in a spring garden

Why customers choose it

Built for year-round growing

Inside a Hoklartherm Riga 5 greenhouse 10x18

Insulated for winter growing

8 mm twin-wall polycarbonate on the body and 10 mm on the end walls keep the heat in, so you can grow year-round without huge heating bills.

Side view of the Hoklartherm Riga 5 greenhouse 10x18

Sheds snow, stands up to wind

The rounded onion profile lets snow slide right off, and an engineer's wind and snow load certification is included below.

Hoklartherm Riga greenhouse roof frame detail

A frame that stays tight

The aluminum profiles are permanently joined, so they won't loosen over time from wind pressure.

Hoklartherm Riga greenhouse window, outside view

Ventilates itself

Four roof windows open and close on their own as the temperature changes, and the oversized rear window adds cross-breeze.

Hoklartherm Riga greenhouse door

Wide, lockable barn door

The Dutch barn door opens top and bottom for airflow and locks with a key.

Shelves inside a Hoklartherm Riga greenhouse

Ready for shelving and a foundation

Add the accessory kit for shelving, or the foundation frame to anchor the greenhouse when you're not building on concrete.

The details

Specifications

Size

Floor area 165 sq ft
Exterior size 9' 8" W x 17' 6" L x 7' 7" H
Walking height 6' 1" at the sides, 7' 6" in the center

Structure

Frame Heavy-duty aluminum, black or silver
Glazing 8 mm twin-wall polycarbonate, UV coated (10 mm end walls)
Insulation R/K-value 3.0
Roof shape Rounded onion profile that sheds snow
Made in Germany, by Hoklartherm

Doors and ventilation

Door 28 3/4" W x 77 3/4" H Dutch barn door, keyed lock
Roof windows 4, each 40" x 24", with automatic openers
Rear window 28 1/2" x 47 13/16" panel, with adjustment arm

Assembly and warranty

Assembly time 2 people, 1 full day (6 to 8 hours with 3 people)
Warranty 15 yrs frame, 10 yrs glazing

Accessory kit (optional)

What's in the Accessory Kit dimension drawing

What's in the Accessory Kit

Foundation frame Anchors the greenhouse in a 6" trench, so no concrete slab is needed
Top shelf 10" W x 17' L, attaches to the greenhouse side
Bottom shelf 25" W x 17' L, hangs from the roof for extra stability
Shelf panels Removable twin-wall polycarbonate, so you can lift out sections for taller plants
Good to know The kit already includes the foundation frame, so you don't need the separate Foundation Frame option

Find the right fit

Compare sizes

ModelFloor areaExterior sizeWalking heightDoorPrice from Link
Hoklartherm Riga 2s Greenhouse 8x7 54 sq ft7' 8" W x 7' L6' 1" at the sides, 6' 11" in the center30" W x 72" H Dutch barn door, keyed lock$4,399 View
Hoklartherm Riga 3s Greenhouse 8x11 81 sq ft7' 8" W x 10' 6" L x 7' 1" H6' 1" at the sides, 6' 11" in the center30" W x 72" H Dutch barn door, keyed lock$4,699 View
Hoklartherm Riga 4s Greenhouse 8ft x 14ft 108 sq ft7' 8" W x 14' L x 7' 1" H6' 1" at the sides, 6' 11" in the center30" W x 72" H Dutch barn door, keyed lock$5,199 View
Hoklartherm Riga 3 Greenhouse 10x11 102 sq ft9' 8" W x 10' 6" L x 7' 7" H6' 1" at the sides, 7' 6" in the center30" W x 79" H Dutch barn door, keyed lock$4,999 View
Hoklartherm Riga 4 Greenhouse 10x14 135 sq ft9' 8" W x 14' L x 7' 7" H6' 1" at the sides, 7' 6" in the center28 3/4" W x 77 3/4" H Dutch barn door, keyed lock$9,899Black frame View
Hoklartherm Riga 5 Greenhouse 10x18 Viewing165 sq ft9' 8" W x 17' 6" L x 7' 7" H6' 1" at the sides, 7' 6" in the center28 3/4" W x 77 3/4" H Dutch barn door, keyed lock$11,699Black frame

Free curbside freight delivery

How delivery works

  1. 1

    You place your order

    Choose your size, color and options. Your greenhouse ships from the manufacturer's warehouse, packed for freight.

  2. 2

    We call to schedule

    We'll contact you to set up a delivery time frame that works for you.

  3. 3

    Free curbside freight

    Delivery is by LTL motor freight on an 18-wheeler. Let us know about tight roads or low wires so we can plan ahead.

  4. 4

    Receive and unload

    Someone needs to be there to receive the delivery. The driver does most of the work but may need a hand.

Foundations and bases are bulky, so we recommend ordering them together with your greenhouse to avoid a separate freight charge.

Good to know

Frequently asked questions

Can't find your answer? Our greenhouse specialists are happy to help you choose.

678-408-8222 Email us
Can I extend a Riga greenhouse later?
No. Riga greenhouses can't be extended after they're built, so we recommend choosing one size larger than you think you'll need. The size comparison table above makes it easy to see the difference.
What kind of foundation do I need?
The greenhouse needs a level base. If you're not anchoring it to concrete, the optional Riga foundation frame is the easiest route: it attaches to the bottom of the greenhouse and is anchored in a 6" deep trench. Foundation dimensions are in the assembly and foundation manual under Technical documents.
How long does assembly take?
Plan on two people for one full day. With three people it typically takes 6 to 8 hours, not counting shelving. Written instructions and an assembly video are included, and you can preview both under Technical documents.
Can I really grow through the winter?
Yes, that's what the Riga is designed for. Its 8 mm twin-wall polycarbonate body and 10 mm end walls insulate far better than the thin-panel greenhouses sold as season extenders, so it costs much less to heat. In colder climates you'll still want a greenhouse heater for the coldest nights.
How does it handle snow and wind?
The rounded onion-shaped roof lets snow slide off, and the aluminum frame profiles are permanently joined so they don't work loose in the wind. The engineer's structural certification with the rated wind and snow loads is available under Technical documents, which is also useful if your town needs a permit.
What does the warranty cover?
The frame is covered for 15 years and the polycarbonate glazing for 10 years. The full warranty terms are under Technical documents.
Is shipping really free?

Yes. Shipping is free. Locations with limited access, such as islands, are rare exceptions that may carry an extra fee, and we'll tell you before anything ships.

Do you offer a price match?

Yes. If you find the same greenhouse for less from an authorized dealer, call or email us with the offer and we'll review it.

Are you an authorized retailer?

Yes. Mulberry Greenhouses is an authorized retailer, so your greenhouse is covered by the full manufacturer warranty.