EzGro's Riga Backyard Greenhouses

Looking for a warm spot to get your seeds started, or to set up your towers?  Look no further, because EzGro Gardens now offers greenhouses!  We’re continually adding high quality items to our shop to make growing as easy and fun as possible, and these greenhouses are no exception with their straight-forward setup and sturdy construction.


Sturdy Construction

The quality that comes with Riga Mark Greenhouses is what you would expect from a high-end commercial greenhouse, but these are designed for hobby use.  The frame on all of these greenhouses is manufactured from extruded aluminum.  Each model of these greenhouses has been tested and proven to withstand harsh winter conditions, including 100 mile per hour winds.  They retain heat when outdoor temperatures are below freezing, even when snow is on the ground.  One of the most notable things about this greenhouse is its unique shape, with the subtle point at the very top, which is similar to an onion.  This is purposely done so that snow cannot pile up on top of it.  This greenhouse was truly built to withstand harsh conditions and allow you to grow fresh produce all year long!

The heavy-duty twin-wall polycarbonate walls really set this line of greenhouses apart from its competition; no hobby greenhouse even comes close to this level of insulation!  In Riga Mark models II, III, and IV, the roof and sidewalls are 8 millimeters thick.  For reference, one nickel is 2 millimeters thick, so these walls are the thickness of 4 nickels stacked on top of one another.  The end-walls are a bit thicker at 10 millimeters, or the thickness of a stack of 5 nickels.  The Riga Mark models V, VI, VII, VIII and XI have 16 millimeter thick walls all around, which is double even the impressively thick walls of the smaller-sized models.  Typical greenhouses only have 4 millimeter walls, which makes ours at least 40 percent less expensive to heat.

The integrity of the craftsmanship on these greenhouses is unparalleled, and the manufacturer offers a superior warranty to back up their product.  The polycarbonate panels are under warranty for 10 years, and the frame is protected for 15 years!  Rest assured that when you purchase a Riga Mark, you are getting the gold standard of greenhouses, along with their stellar warranty.



A Dutch door comes standard with each of these greenhouses.  It is the perfect solution to let the breeze in, while keeping critters out.  The doors are even lockable for security purposes.  Even more helpful, the doorframe is 29.6 inches wide to allow for a standard wheelbarrow to comfortably pass through.  This feature is especially useful for planting and harvesting.

In order for the grower to take maximum advantage of natural ventilation, all of the Riga Mark Greenhouses come standard with a large window on the back wall with dimensions of 42” tall and 30” wide.  The window on the roof is equally impressive at 40” by 24”.  Rest assured that the kit comes standard with an automatic roof-window opener for ease of access.  The best part of the window opener is that no electricity is necessary to operate it!  Based on the interior temperature of the greenhouse, it will open and shut on its own.

These two huge windows and the Dutch door, along with the twin-wall polycarbonate frame, allow the interior to stay cool during summer months.  This greatly reduces or even eliminates the need to spend money on cooling mechanisms.  Of course, the superior insulation also translates to minimal heating bills during winter months.


Easy to Build

Riga Mark greenhouses are designed with the customer in mind, and no stone has been left unturned in the production of these impressive greenhouses.  While assembly is required, clear written instructions as well as an instructional DVD are included in your purchase.  The frame has been designed so the pieces of aluminum simply slide into one another, simplifying the process even more.  The greenhouse will take two people about one day to assemble.  I can’t think of any structure in which people can walk around that takes such little time to put together!

It is important to look into zoning restrictions in order to build a greenhouse in any location.  Riga Mark greenhouses do not require a slab, and are not considered permanent structures.  Your local government typically provides this information, but a homeowner’s association may also have restrictions that need to be looked into.  If there is a restriction, these agencies may make an exception for a greenhouse because of its unique ability to help grow food locally.


Optional Add-Ons

Base Kit:

A sturdy, level space is necessary to situate the greenhouse on top of.  We offer a Base Kit made specifically for each model of the Riga Mark Greenhouses.  The Base Kits are made from durable extruded aluminum and are as durable as the greenhouse’s aluminum frame.  The base is six inches tall, and the greenhouse frame sits directly on top of the base.  If you choose, the base may be filled with a substrate such as sand, gravel, or concrete, though this step is not required.


You’ll likely need a place to put your seedling trays, and ideally they would be situated at waist height.  Riga Mark shelves hang from chains attached to the roof of the greenhouse instead of on braces to maximize storage space.

Grow Lights:

While there aren’t lights specifically designed for these greenhouses, options are available in the Lighting section of our shop.


Additional windows on the sidewalls or the roof can be added.  This would be beneficial in areas where temperatures regularly exceed 90 degrees Fahrenheit.

Heating/ Cooling:

Additional heating or cooling is usually not needed, but there are some methods we recommend if you find its necessary.  An electric fan may be installed by drilling a small hole for the cord through the front or back wall of the polycarbonate.  A small radiator-style heating unit would work for providing additional heat.

We hope you enjoy these greenhouses to extend your growing season!  For more information on Riga Mark, click on the Backyard Greenhouses page.

Here are some frequently asked questions

How to keep greenhouse clean?

Wash down with mild soapy water annually.

Does the Riga Greenhouse require maintenance?

No routine maintenance is required, however we recommend annually checking that all nuts and bolts and screws are still tight – note this is not a requirement just a suggestion.

Available Options:

Additional Roof Windows with Automatic Opener – recommended in case the Riga greenhouse is to be actively used in very hot climates (during the summer) ie temperatures in excess of 90º F.

Does the Riga greenhouse require shade cloth?

If you are planning to use the greenhouse to grow and house exotic plants in during day time temperatures in excess of 85-90º F than virtually any greenhouse will need some kind of shade cloth and or missing system in order to keep temperatures down.

What other accessories do we offer?

  • A bag with 10 plastic hooks – these can be used to attach a string to, to guide tall growing plants to (i.e. Tomatoes and beans).
  • A set of 5 adjustable metal hooks: for hanging flower baskets and/or ceiling lights and fans.

Are there other window and/or door options?

Yes, additional roof windows (with Automatic Openers) and it is possible to put an additional door in the back wall

If for some reason some part breaks – can I get a replacement part?

Not a problem – we carry spare parts of all parts of the greenhouse.

Can I make the unit longer/bigger latter on?

  • Unfortunately you cannot. The reason for this is that the roof beam, Base Profiles and the Lateral Supports are the same length as the greenhouse originally bought -this ensures optimal strength of the unit.
  • Roof Beam and Base Profiles are one piece and cannot be extended

Foundation Frame / Mounting system

  • The Foundation Frame attaches to the bottom of the Riga greenhouse profiles and usually sits in the ground, but it can also be mounted on top of 6” x 6” treated lumber, a concrete or brick wall to provide 5” of additional headspace inside.
  • This frame is designed such that when “filled” with dirt all around the greenhouse cannot and will not blow away in anything less than a hurricane wind. (We do not guaranty this)

How strong are the shelves?

  • Strong enough to put several flats with plants on them or take a nap
  • Hanging from chains is stronger than traditional braces.

What type of flooring do we recommend?

  • Please do not put any greenhouse on a concrete slab. Standing water on concrete is dangerous, especially when it freezes over.
  • A greenhouse floor should be free draining.
  • Usually people will create some sort of path (i.e. flag stones) down the center of a greenhouse – to walk on. The rest of the ground might be covered with riverbed stones, pea gravel, or pine straw or a similar material.
  • Other drawbacks of a concrete slab: stays too cold in the winter and too hot in the summer (reflects heat back up – making things even worse inside).
  • We do recommend, removing all grass and weeds etc. from inside the greenhouse area before assembling the greenhouse. And to cover this area with a weed control mat.
  • You can put a greenhouse on a deck but be aware that this will allow cold air to blow in through the deck. We don’t recommend this.

Snow load/capacity:

  • Due to the aggressive angle of the roof-line it is impossible to measure the Riga snow load capacity – snow and other debris simply slide down the roof.
  • As the roof has no “shoulder” there is no ridge, for any snow to build-up on.
  • However, the roof is more than strong enough to allow a 185 lbs person to stand on top of it – in the middle of the polycarbonate panels.

Wind resistance:

  • Although there is no official wind rating the Riga greenhouses were driven on a flat bed truck down the German highway at 80 miles per hour and suffered no damage.
  • Basically due to its unique roof slope strong winds are diverted over the roof.
  • Additional wind resistance is provided through the 4 lateral support bars, which span from the front to the back of the greenhouse.
  • Recommendation: like any greenhouse the Riga greenhouse must be fixed to its location. We offer a specially heavy duty foundation frame – which can also be used to raise the greenhouse up to 5”.

Zoning Restrictions:

  • In many areas of the country there are restriction with respect to adding some kind of permanent structure in your back yard, set by either your local government or by your neighborhood association.
  • Most common restriction: everything over 100 sq. ft. needs a permit
  • Or anything requiring a slab.
  • However, we are finding that more and more places are willing to make exceptions for a nice greenhouse – associations understand and respect the environmental benefit of growing your own food and plants. Just ask them for permission.
  • This greenhouse does not require a slab
  • It is not a permanent structure.

Does the greenhouse require heating in the winter?

Yes, it might depend on outside temperatures and the needs of your plants. Standard recommendation is to keep the temperature inside at about 50-53º F.

Can I install an electric fan?

Yes, you can – simply cut the required hole with a utility knife in the polycarbonate glazing either in the back or front walls

How are the roof windows attached?

  • FYI: with most greenhouses they hang form simple hinges, which can break if the window is left open in heavy winds.
  • The Riga roof windows are attached with a ‘tongue and grove” hinge system, which spans the full length of the top profile of the roof window
  • The top profile sits “inside” a grove in the roof beam.
  • It is attached by sliding the assembled roof window down the grove in the roof beam from either end of the roof beam.

How does the Automatic Window Opener work – does it need electricity?

  • No electricity is needed.
  • It comes with a special cylinder (black) filled with unique paraffin oil, which expands, and contracts due to temperature changes. It pushes the window open when it gets hot inside and closes the window when it cools down.
  • Temperature range is adjustable

What kind of ventilation is provided?

  • Automatic Window Openers with each roof window
  • An oversized 30” x 42” or 30” x 49” rear-wall window
  • An oversized Dutch barn style front door -30” x 72” or 30” x 79” high.
  • Additional windows can be added.

Why is ventilation so important?

Because, in this country temperature can change drastically from cold nights to hot afternoons. To compensate for this, the Riga greenhouse comes standard with larger and more windows than similar greenhouses. For this reason it comes with an oversized window in the back wall. In addition, you can leave the top half of the front door open allowing a breeze to flow through.

Why use twin-wall polycarbonate instead of glass?

  • In the old days twin-wall polycarbonate glazing did not exist and therefore all older greenhouses have only glass or a corrugated plastic type walls.
  • Cheap glass was/is cheaper than good polycarbonate
  • Since the invention of the twin-wall polycarbonate glazing it has become the new material to use – even the professional growers are using it now.
  • Twin-wall polycarbonate glazing is much more efficient – like a double pane window it provides much better insulation.
  • At least 40% cheaper to heat – for a same size greenhouse with 4 mm single layered glass or less.
  • Twin-wall polycarbonate glazing defuses direct sunlight – glass does not. This is important to sensitive plants.
  • Provides much better UV protection
  • Easier to handle – not dangerous
  • Easier to assemble – safer and lighter
  • Safer for children and pets

What is a (proper) greenhouse?

  • Usually, a structure which uses at least 4 mm glass or better still at least 8 mm twin-wall polycarbonate glazing. These units are designed to be used in cold weather – including continuous day-time frost conditions
  • A unit designed to be kept comfortable (about 50-53ºF) during the middle of the winter with out costing an arm and a leg to do so.
  • Less insulation can mean significantly higher heating costs.

What is a Season Extender?

  • It is a structure covering flowers and plants designed to prevent a late frost from damaging the flowers and plants. They are too expensive, relatively speaking, or sometimes impossible, to keep warm enough (above 50ºF) during day time frost.
  • These structures usually include all “greenhouses” which use 5 mm or less twin-wall polycarbonate glazing. Or use only single layers of heavy polyvinyl sheeting, or 3 mm or less single layered glass.
  • To keep these warm enough in the middle of the winter you need so much heat that often the plants near the heating unit are damaged from too much heat.
  • The cost of heating these units properly is too high; in the long run it is cheaper to buy a better-insulated greenhouse.

Cost Justification -Why do prices of greenhouses vary so much?

  • Look at it this way: why is there such a wide price range in cars – they all have an engine, 4-wheels and can get you from one place to another? The more expensive the car the more value/features etc. you generally get. This is also the case with greenhouses.
  • Because: for one thing the experts don’t call all covered garden structures greenhouses, as is currently the case in our country. But in Europe where the greenhouse concept was invented over 100 years ago, they consider any structure using less than 8 mm twin-wall polycarbonate not a proper greenhouse but a “season-extender”.

Why buy a greenhouse in the first place?

  • Generally: To grow your own plants, vegetables and flowers from seed
  • To protect plants, shrubs, small trees etc. against frost during the winter.
  • To show-off – to pretend to be a serious gardener.

Who should buy a Riga greenhouse -The Perfect Customer?

  • Usually a some what serious gardener: either likes to grow most of their plants and vegetables from seeds, and wants to start before the winter is over, or
  • The serious gardener, who wants to grow some of their own vegetables and flowers during the winter season.
  • Some one who has already had experience with a greenhouse – but they bought an entry-level unit – and they now are ready to buy a real-greenhouse (to upgrade).
  • An orchid grower/lover.
  • Some one very concerned about eating only organic foods – very health conscious.

How long does it take to assemble the greenhouse?

Installation requires two people minimum Not considering site preparation – the assembly should take between 6-10 hours, depending on how many shelves are bought and/or the foundation frame is added.

Does the warranty cover damage due to severe wind or a hail storm?

No it does not. However, the type of weather which would damage the Riga greenhouse would be such that it would also damage your main house and/or other structures in your garden. In which case this damage would be covered by your home-owners insurance policy.

General Description Materials

  1. Frame: Smooth finished anodized aluminum frame/profiles
  2. Glazing: UV coated 8 mm Twin-Wall Polycarbonate Glazing on the sides, and 10 mm twin-wall polycarbonate glazing in the front and back walls
  3. Heavy duty rubber seals
  4. Silicon caulk to seal around windows
  5. Door handle with key lock

What are other unique features of the Riga greenhouse?

  1. It comes standard with oversized rear-wall window, 1 or 2 large roof windows (depends on the size) and an oversized 30” wide Dutch barn style door.
  2. 8 mm or 16mm twin-wall polycarbonate glazing as side panels
  3. 10 mm or 16mm twin-wall polycarbonate glazing in the front and back walls.
  4. Roof windows come with Automatic Window Openers
  5. Heavy-duty rubber seals are used on all the windows and doors as well as at the bottom and top of each of the large side glazing panels.

Warranty: Aluminum Profiles: 15 years and Polycarbonate glazing 10 years, both against manufacturer’s defects. The Warranty of the glazing panels is prorated after 5 years.

Why buy a Riga Backyard Greenhouse?

  1. If you intend to grow your own food during the winter, then the Riga greenhouse is the most suitable product – it offers more insulation than other units.
  2. Its special shape is designed to offer optimal head room inside, but with enough slope on the outside so that heavy snow loads slide down and severe winds blow over the greenhouse.
  3. The Riga Greenhouse comes with significantly larger and more windows than other Greenhouses.
  4. It has a large Dutch Barn style door – with a key lock in the door handle
  5. Its shelves hang from the roof and do not sit on braces – more storage space.
  6. The unique design of the Riga greenhouse has the best ratio between aluminum framing and polycarbonate panels, which allows for maximum light transmittance and less “moving” shade. (The side glazing panels are wider (40”) than those of other greenhouses, as such the Riga greenhouse utilizes significantly less aluminum profile materials)