???? How to Choose the Best Greenhouse Kit (2019 Update)

How to Choose the Best Greenhouse Kit

Written by Brittani Sponaugle and updated on April 4, 2019
Choosing the Best Greenhouse Garden Kit

While there are many beautiful landscapes and sceneries scattered around the world, there’s nowhere on this Earth that has the ideal climate for gardening all year round.

Temperatures are either too hot in the summer or too cold in the winter, and the survival rate for many plants during times of extreme weather are slim unless they are somehow protected. That’s where modern-day greenhouses come in.

The following article will take you through some of the reasons that it’s a good idea to invest in a greenhouse kit and what to look for when buying one. 

Then, if you’re not already convinced, we’ll show you a few examples of some of the best greenhouse kits currently available, and how they fare up against our tough analysis.

Why Buying a Greenhouse Kit is a Good Investment

Having your own greenhouse gives you a way to enjoy your garden the whole year round. It provides you with a controlled environment that you can manipulate to the exact conditions your plants need to thrive.

With a greenhouse kit, you can choose the size, shape, and design of your greenhouse, as well as most of the materials. So in addition to getting somewhere practical to grow your plants, you can also get something aesthetically pleasing to complement your garden.

What to Consider When Buying a Greenhouse Kit

There are a lot of choices out there when it comes to greenhouse kits, and it can be confusing if you don’t have any idea what you’re looking for. Thankfully, the following section should help with that. Here we’ll share with you some of the more important things to consider when buying a greenhouse kit.

Size of the Kit

Greenhouse kits come in all kinds of shapes and sizes, but generally you can separate them into three categories: small/mini, medium, and large. To determine the size greenhouse you need, think about what it is you plan on growing.

A mini greenhouse kit is ideal if you’re only planning on potting a few plants for your own benefit or don’t have a lot of spare space in your garden. They’re usually very easy to set up and don’t cost a fortune either. To give you an idea as to their size, we would consider both 6’ x 2’ and 6’ x 8’ greenhouses to be of the mini variety.

Medium-sized greenhouse kits are great for anyone who has a little more spare space. Of course, they are a little trickier to assemble, but you can fit quite a lot more in them than a mini greenhouse. A typical medium-sized greenhouse is around 8’ x 12’ or 10’ x 12’ in size.

If you’re planning on doing some serious bulk gardening, provided you have the room for it, you may want to consider getting a large greenhouse. Having a large greenhouse in your garden will allow you to grow pretty much anything. In terms of size, you’ll be looking at something in the region of 15’ x 7’, 10’ x 20’, or maybe even bigger.

Greenhouse Location 

Once you’ve worked out the size of greenhouse kit that’s going to best meet your needs, it’s time to work out where to put it. This is a very important step, as giving your plants the right amount of light is essential for their growth. Ideally, you should opt for a location that gets a minimum of around 6 hours of sunlight a day.

It may be beneficial to have your greenhouse somewhere near an electrical outlet and also where you have ready access to water. This will make your life much easier when needing to use any electricity or to water your plants. Also, try and avoid placing it where lots of obstacles are in the way.

Foundation Type

While it’s not always necessary to build a concrete foundation for your greenhouse, it is something you may want to consider if you live in an area that’s prone to cold weather, as it will help contain the heat. Many greenhouses have floors made up of gravel on top of sand and hardcore because you can damp it down in the summer to ensure the air remains humid. It also allows for easy drainage.

Drainage for Greenhouses

Having adequate drainage for your greenhouse is paramount. Generally speaking, you can do this in one or two ways: by digging a trench or by using gutters. Both will give any excess water somewhere to go and will lessen the chance of the soil becoming oversaturated. This will help prevent the growth of any algae or disease and keep unwanted pests such as mosquitoes at bay, too.

Building Regulations

Some local laws (and your HOA, if you have one) place restrictions on the size of greenhouse you’re allowed, as well as where you can put it. So before you even purchase your greenhouse kit, it’s always a good idea to check with the authorities to ensure that you’re not breaking any laws with what you’re planning. Failure to do this could result in a lot of time and money wasted.

Frame Material of Greenhouses

When it comes to greenhouse kits there are various frame material options to choose from, all of which have their pros and cons. However, the most popular frame materials you’ll see are:

Aluminum - This is one of the most commonly used materials when it comes to frames, as it’s lightweight and easy to use. It’s also less expensive than using a composite frame, and you don't have to worry about rusting, either.

The main thing to be aware of with aluminum frames is the strength rating, as this will vary across greenhouse kit models. While you can always anchor down aluminum frames, if you live in an area that’s particularly windy you may want to consider a more durable frame option, such as Solexx or wood. You should also be aware that aluminum doesn’t make for a good insulator so expect some heat loss when using this kind of frame.

Wood - A lot of people prefer to use wood for their greenhouse frame. Not only does it look good but it’s also extremely durable. Wood is also a very good insulator.

The biggest problem with wood is that it’s susceptible to rotting caused by disease or mildew. To try and avoid this, make sure you use a high-quality wood such as cedar or redwood.

Resin - This is a strong kind of plastic that’s often used in greenhouse frames. It’s cheap and provides good insulation.

Just be aware that resin frames don’t quite have the same strength as metal frames and if overexposed to the sun warping may occur. 

Steel - Greenhouse kits often use galvanized steel frames, as they’re heavy-duty and likely to last a long time. They’re pretty low-cost too.

The downside to using steel is that it is heavy, which makes assembling and transporting these kinds of frames more difficult than most others. 

PVC - The cheapest frame option of them all is PVC. It’s also the easiest to work with due to its super flexibility, and popular because it is a good insulator.

But, while PVC is a good insulator, it just doesn’t have the same strength other frame materials can offer.

Solexx - These frames are rather unique as they’re made up of a combination of composite tubing, steel, and PVC. While the composite tubing and steel give the frame its incredible strength, the PVC provides adequate insulation for the greenhouse. It also reduces the amount of condensation build-up on the frame. These frames are great at holding up against harsh winds and damp weather and are really easy to clean. The only real downside to Solexx is that they are the more expensive option.

Glazing Material for Greenhouses

Glazing refers to the panel material that covers the frame of your greenhouse. When considering what glazing to have, there are two things to bear in mind:

  • Thermal insulation (R-value) - This will tell you how energy efficient the glazing is. The higher the R-value, the better it will be at insulating your greenhouse.
  • Light transmission percentage - This refers to the amount of light that’s able to penetrate through the glazing without being absorbed or reflected. The higher this percentage, the more light your crops will receive.

And just like frames, there are many different materials to choose from when it comes to glazing panels for your greenhouse. The most popular options are:

  • Solexx - It may be the most expensive option, but Solexx offers high insulation value with excellent light diffusing properties.

  • Tempered glass - Unlike standard glass, tempered glass panes are durable, impact-resistant, and provide good insulation. However, they are one of the more expensive options.

  • Multi-wall polycarbonate - Polycarbonate is a strong plastic that has a transparency similar to that of glass. Multi-wall polycarbonate refers to glazing that’s made up of layers, similar to that of double-pane glass. It’s much stronger, longer lasting, and more cost-efficient than glass, and has a higher R-value.

  • Corrugated polycarbonate sheets - Greenhouse glazing often uses these sheets, as they’re inexpensive, lightweight, and extremely durable. The main disadvantage with corrugated polycarbonate sheets is that they are prone to discoloration, though most manufacturers provide some kind of warranty for this.

  • Polyethylene film - This is the best option for anyone on a tight budget. It’s super cheap and easy to use. Because it’s translucent, it retains heat really well. The downsides are that it degrades quite quickly and is prone to stretching and sagging.

Ventilation for Hot and Cool Air

To give your plants the best start in life and throughout, you need to ensure there’s adequate ventilation in your greenhouse.

The best way to do this is by having one roof vent that covers around 20 percent of the floor area on either side of the roof ridge. You can use side vents to provide extra ventilation, but these should be in addition to side vents instead of an alternative to them.

Best Greenhouse Kit Reviews

To help you buy the right greenhouse kit for you, we’ve compiled a list of some of the most popular options available at the moment and how well we feel they measure up to what’s expected of them:

Best Small Greenhouse Kits

Rion EcoGrow 2 Greenhouse

We’ve put this under the small category, as there’s a 6’ x 6’ option available. But the Rion EcoGrow 2 Greenhouse is also available in a 6’ x 8’ size, a 6’ x 10’ size, and a 6’ x 12’ size. With a frame that’s made from heavy-duty, UV-protected resin and thick twin-wall polycarbonate glazing, it’s the ideal choice for any hobby gardener looking for a place to grow a few plants.

Rion EcoGrow 2 Twin Wall Greenhouse, 6' x 6'

It has a latched door for easy access in and out the greenhouse and an integrated roof vent to ensure adequate ventilation inside. Assembly is pretty easy thanks to its innovative pin and lock system and its barn-shaped design allows extra headroom for more comfortable gardening.

  • Sturdy frame made from UV-protected resin
  • check
    4 size options available
  • check
    Easy to assemble
  • Only one roof vent
  • ban
    No hardware supplied for fixing to a foundation
  • ban
Quictent Greenhouse Mini Walk-in Portable Plant Garden

If you’re looking for a greenhouse that’s functional, easy to use, and won’t cost you a fortune, be sure to check out this Quictent mini greenhouse. Measuring in at just 4.6’ x 2.4’ x 6.4’, this greenhouse is the perfect solution for anyone lacking space in their garden.

Quictent Greenhouse Mini Walk-in 3 Tiers 6 Shelves 102lbs Max Weight Capacity Portable Plant Garden Outdoor Green House 56'x29'x77'

The frame itself is made using powder-coated steel poles that are both durable and long-lasting. The transparent PVC cover is 100% waterproof and UV-protected, helping to keep your plants safe at all times. There’s a double-zippered front door for easy access and better ventilation, and it even comes equipped with six removable shelves for added convenience.

  • Great price
  • check
    Compact design
  • check
    Zippered cover enables easy access
  • Extremely lightweight
  • ban
    Shelf capacity is just 17 lbs max

Best Medium Greenhouse Kits