Do Portable Greenhouse Kits Work?

A greenhouse is a fantastic investment that will take your garden to the next level. You may feel hesitant to build a permanent greenhouse in your garden for a few reasons – limited space, budget constraints or living on a rented property. These factors do not need to hold you back from growing the delicate flowers or vegetables that you dream of!

Portable greenhouse kits work just as well as regular greenhouses to create a stable, warm, and humid environment wherein one can grow tender plants and germinate seeds. Greenhouses protect plants from extreme temperatures, strong wind, and snow, and they are great for extending the growing season.

Portable greenhouse kits, also known as plant houses or pop-up greenhouses are a brilliant budget-friendly, space-saving alternative to building a traditional greenhouse. If, like me, you love growing exotic plants like orchids, you understand the frustration of trying to keep your plants under the perfect conditions all year-round. Before we moved to our forever home on our farm, we were hesitant to build a glass greenhouse due to the high cost and not being able to take it with us when we move. We ordered a portable greenhouse kit online and found it the perfect solution to our situation!

The benefits of growing in a portable greenhouse

Creates ideal growing conditions. A greenhouse works by capturing heat during the day and storing it overnight. The ground under the greenhouse warms from the sun’s rays and radiates heat, buffering the temperature range inside the greenhouse. Increasing temperature and humidity optimizes germination conditions for seeds and growing conditions for vegetables, fruit, and flowers.
Start your own seedlings from seed. Filling up your garden beds by buying plants from the nursery can be very expensive! It is much more cost effective to start baby plants from seed. One can maximize germination by using a greenhouse and get a huge number of plants cheaply.
Extend the growing season. One can sow spring and summer seeds much earlier in a greenhouse and give your plants a head-start. Planting out larger seedlings will increase their potential.
Ensure consistent production. In the winter, when it is too cold to grow vegetables outside, one can keep producing food inside the greenhouse.
Protection from pests. Keeping plants inside a greenhouse protects them from garden pests like slugs and snails.
Grow exotic plant species. One can grow heat-loving, tropical plants anywhere in the world! Orchids, bromeliads, Venus fly traps, and other interesting carnivorous plants thrive in greenhouse conditions.
Pack it away when you do not need it. If you only need to use the greenhouse for half of the year, a portable greenhouse can be packed away to give you more growing space.
Move it to the perfect spot. In winter, one can move your portable greenhouse as the sun moves, always ensuring it is in a sunny spot. Likewise, in summer, one can move the greenhouse into the shade, to prevent it from overheating.
Move it with you. If you are living on a rented property, having a portable greenhouse is great because you can pack it up and move it with you when you move to a new house.

Portable greenhouse disadvantages

There are two minor disadvantages to a portable greenhouse. It may be subjective, but to me they lack aesthetic appeal. I love my vegetable garden to look polished and beautiful, and a tent can be somewhat of an eye sore. It may be a good idea to look for a sunny spot around a corner on the south-facing side of your property to put the greenhouse.

Secondly, if you are growing plants that are insect pollinated inside a greenhouse for the whole growing season, their pollination will be disrupted as insects cannot reach the flowers. It is therefore more difficult to grow some fruits and leafy vegetables inside a greenhouse.

Different types of portable greenhouses

There are a range of portable greenhouse kits on the market, varying in size, shape, and materials. Some portable greenhouses are easier to move than others. Whether you have a tiny balcony garden or a large homestead, you are sure to find the right portable greenhouse option for you!

Mini greenhouse tent. They are often referred to as a plant house or pop-up greenhouse. These are the smallest and generally the cheapest portable greenhouse kits on the market. They have a lightweight construction and can easily be picked up and moved without disassembly. Some models have vertical shelves, while others are longer and more horizontal, designed to be placed over garden beds. Greenhouses like these are not designed to be walked into. These tents have flaps that can be rolled up and tied for ventilation. The greenhouse frame is made of rigid tubing (iron, PVC, or fiberglass) and the cover is usually thick, clear plastic. They are very simple to assemble – no tools needed! Mini greenhouse tents are ideal if you have a small growing space outdoors (on a deck, patio, or balcony) or even indoors. Their low cost ($25-$70) and size make them perfect for those who are new to gardening or growing in a greenhouse. Their light weight makes them highly portable, but you will have to weigh or stake them down to prevent them blowing away on stormy days!
Small walk-in greenhouse. These portable greenhouse kits are still small enough to fit in a limited amount of space but provide more functionality because you can walk in and work inside. You can set them up outdoors on grass or a prepared bed, or on a concrete surface, like a patio or balcony. Like the mini greenhouse tents, these need to be weighed down or staked into the grass to prevent the lightweight structure from blowing away in the wind. Most portable walk-in greenhouses are quick and easy to assemble, often without tools. They consist of a rigid tube structure (iron, PVC, or fiberglass) and a clear plastic covering. Depending on the size and design, these greenhouses cost $45-$100 – a great option for beginner greenhouse gardeners.
Larger walk-in polytunnel. For a large greenhouse that is more durable but still portable, a polytunnel is perfect! They can be set up over garden beds over winter to protect against frost. Polytunnel kits consist of curved steel poles that form the tunnel structure and a thick, clear plastic covering. They are more difficult to set up, due to the size and shape – you will need a second pair of helping hands. Polytunnel greenhouses are not as easy to move, so are a good option if you do not want to move the greenhouse frequently. All models have at least one door, but two-door models have better ventilation. Look for a model that has vents for airflow. These are a more expensive option ($125-$300) and are a great choice for more experienced gardeners who need more growing space (generally 12-20 feet in length and 6-7 feet tall). Some designs are big enough to store a few gardening tools inside.
Compact greenhouse. The most expensive of the portable greenhouse kit options ($375-$1000), compact greenhouses are much more durable that other types. They are not designed to be moved frequently, as they are heavier and must be disassembled. The frame is usually made of lightweight aluminum, and instead of a plastic sheet covering they have UV-resistant polycarbonate sheets. Compact greenhouses have hinged door and windows for ventilation and some designs even have gutters and a locking mechanism. While these greenhouses are much sturdier than the above types, they still need to be weighed down in tornado or hurricane conditions. Most models specify to what wind speeds they are resistant. The greatest advantages of this type is their aesthetic appeal and their durability.

Choosing the right portable greenhouse kit

During 2020 many more people from around the world realized the value of gardening, both in terms of growing your own food and for the mental health benefits. The rise in demand for portable greenhouse kits means there are a huge range of options available on the market. Look carefully at the specifications and measurements to ensure that you purchase the right greenhouse for your garden’s space and needs. Make sure you are buying a whole greenhouse kit and not only the frame or the cover, as these are sometimes sold separately. Here are some things to consider when choosing a portable greenhouse kit:

How much space you have? Portable greenhouses come in all shapes and sizes. Do you have a paved courtyard or balcony garden, or a large growing area? A greenhouse needs to be set up on a flat area – do you have a space large enough that is flat or can be flattened?
What you need the greenhouse for. Are you wanting a greenhouse to create an area for seed germination, or do you want to grow plants in the greenhouse all year-round? If you are interested in the latter, a larger portable greenhouse would be more suitable, because the plants you will be growing in the greenhouse will need more space.
Your budget. There are a range of portable greenhouse kit options to suit any budget. Generally, the more expensive models are larger and more durable, but there are well-designed, functional, low-cost options out there. One can even build a portable greenhouse out of recycled materials.
Ease of set-up. Are you confident with DIY projects and power tools or are you looking for a greenhouse kit that can pop up easily in minutes? Some larger portable greenhouses require tools to set up, whereas smaller ones are as simple as putting up a camping tent.
Durability. How long do you want your portable greenhouse to last and does the area you live in experience extreme weather events? If you live in a place where heavy snowfalls and gale force winds are common, a small portable greenhouse tent will not last long. Consider the materials that make up the greenhouse kit. Lightweight PVC or fiberglass poles are less durable, whereas metal structures will be able to withstand greater snow loads and wind speeds.
How often you want to move it. Think about how portable you need the greenhouse to be. If you are wanting one that can move frequently, look at kits that are lightweight and easy to assemble and take down. If you only need to move your greenhouse once or twice annually, you could consider a heavier, sturdier model. Greenhouse kits can also be modified to include wheels.

Portable greenhouses vs regular greenhouses

If we compare a portable greenhouse to a regular greenhouse, one can see that there are benefits and downsides to both options. Before committing to a permanent greenhouse structure, it may be a good idea to buy a portable greenhouse kit first to learn how to grow in a greenhouse and figure out how you want to use it in your garden. A portable greenhouse is less of a commitment, and if you decide to upgrade to a permanent greenhouse, one can pack up the portable greenhouse kit and sell it.

Portable greenhouse	Regular greenhouse
Quick to set up	Takes longer to build
No tools required	Building requires tools and expertise
Does not require a foundation	Require a foundation to be built
$50-$1000 – cost effective	$700-$20000 – more expensive
Less durable in windy, snowy conditions	Able to withstand extreme weather
Greenhouse kits come with shelving	Shelves must be built separately
Thin covering – not as warm	Rigid covering like glass – holds more warmth
Zipper doors and window flaps	Hinged doors and vents
Ideal for starting seedlings or hardening off	Great for growing plants
Not always possible to walk in/work inside	Walk in and work inside comfortably

The importance of proper ventilation

Ensuring that your portable greenhouse kit is designed with door or window flaps for ventilation is vital. Regardless of the size of your greenhouse, ventilation is always required. Without good ventilation, the greenhouse will get too hot and humid and fungal diseases, such a powdery mildew and blight will take over the greenhouse.

Grow plants with enough space in between individuals and prune dense plants to further increase air flow between them. Putting a fan into a small greenhouse to ensure proper ventilation is a good idea, however, a larger greenhouse will need vents that can be opened. One should open the vents in the morning and close them at night.

Choosing the right location for a portable greenhouse

One of the greatest advantages of having a portable greenhouse is that there is no pressure to set it up in the perfect spot first time around! It is advised to put a greenhouse in an area that gets sun for most of the year, especially through fall and winter. This is usually on the south or southeast side of your property, depending on where you live. Position the greenhouse so that its length runs from north to south, maximizing sun exposure during the day. While sunlight is important, harsh afternoon sun can be too intense for sensitive plants and seedlings, so choose a place that gets dappled afternoon shade.

Which plants grow well in a portable greenhouse

Heat-loving, tropical plants like ginger and turmeric grow very well in a greenhouse! They thrive in the humidity and warmth. Okra is another interesting, tropical crop that you can grow in a greenhouse.

In colder regions, one can grow grape vines in a greenhouse with a lot of success! The plants take a while to grow big and produce grapes, but they are well worth the wait!

Cucumbers, tomatoes, eggplants, and basil are also fantastic candidates for growing inside a portable greenhouse. Because they are all annual crops, you can grow them even if the greenhouse is only working for part of the year. These four species are also great companion plants and will grow well together inside a greenhouse.

Did you know that you can grow your own luffa sponges for the shower? Luffa plants are closely related to cucumbers and grow well inside a greenhouse!

Although they do not mind cold weather, lettuce grows rapidly inside a greenhouse.

Green beans and runner beans enjoy the warm conditions inside a greenhouse.

If vegetables are not your thing, you can grow interesting, exotic plant species, like cacti, orchids, bromeliads, or carnivorous plants!

Maximize growing space in a portable greenhouse

It always feels like there is never enough growing space, especially inside portable greenhouses that are generally on the smaller side. A great way to maximize growing space inside a greenhouse is by growing vertically. There are a few ways to do this:

The string method. This works especially well for tomatoes. Run a wire or thick string horizontally across the top of the greenhouse, in line with the bed you are planting into. Tie a string every 30-40cm and let them hang down towards the soil. Plant a tomato under each hanging string and insert a deep stake beside each plant. Tie the hanging string to the stake so that the string is taut. As the plant grows, wind it around the string and keep pinching off lateral shoots or suckers. In the case of tomatoes, this will produce bigger, healthier fruits. This method is great for using inside a greenhouse because it promotes good air flow between plants.
Stakes. Another great way to encourage plants inside a greenhouse to grow vertically is by using wooden or metal stakes. The cheapest option is finding straight, strong sticks in your garden or at the park. Bamboo stakes are fantastic! Knock the stake securely into the ground and plant next to it so that as the plant grows, you can use twine or florist’s wire to loosely secure the plant to the stake. Runner beans, cucumbers and luffa grow well using this method.
Shelving. If you are using your greenhouse to start annual seedlings, one can maximize vertical space using tiered shelves. It is easy to build your own shelves cheaply from recycled materials. Wire mesh is ideal, as it allows for good drainage. Position shelves so that they do not shade one another.

Heating a portable greenhouse

Portable greenhouses are generally not as large as regular greenhouses. Having less soil surface to heat, will mean that less heat is retained in the greenhouse overnight. If you live in an area where winters get very cold, you may need to add additional heating to your portable greenhouse.

A small greenhouse that is relatively near the house can easily be heated using a small electric heater with a fan. Remember to cover the plug connection in plastic to prevent it from getting wet.

In a larger sized portable greenhouse, one can put a portable air conditioning unit, however this can be rather expensive! One can harness the (free) power of the sun to heat a greenhouse too. Fill black 25-liter drums with water and leave them in the greenhouse (under the shelves are a good spot). They will heat up during the day and retain the heat overnight, warming the air in the greenhouse.

A cost effective, energy-free, and organic way to heat your greenhouse is with a compost hot bed. Nail together 4 planks to form a rectangular box, about 60cm in height. Fill the box will alternating layers of fresh manure and straw. Water it well and cover with a black plastic tarp. The manure and straw will be processed by billions of microorganisms, slowly turning it into compost. The heat of the organisms’ digestion will cause the hot bed to heat up. This will take 12-24 hours, depending on the size of the box. Place seedling trays on top of the hot bed, this will keep the soil nice and warm, around 24 degrees Celsius – perfect for germination.

Certain types of compact greenhouses are designed specially for extremely cold conditions. These are covered with a double layer of polycarbonate sheeting with an air pocket in between that provides extra insulation and heat retention. By investing extra money into a design like this, one will save on additional heating costs for the greenhouse.

Irrigation inside a portable greenhouse

One of the greatest advantages of growing inside a greenhouse is that one can control the growing conditions. To keep my greenhouse at the ideal relative humidity (85%), I installed a simple misting system that connects to my garden hose. The thin pipe with small spray nozzles has been cable-tied to the inside of my greenhouse’s frame. I turn the misting system on and off, as needed, but one could put a digital timer on the tap (great for when you want to go away and can’t find anyone to water your plants!).

It is important not to overwater plants inside a greenhouse. This can easily happen, because the high humidity in the air causes the soil to remain wet for longer. Stick your finger into the soil inside the greenhouse to check that it has dried out enough before watering. Root rot and fungal diseases can ruin your greenhouse crop if they are overwatered!

Conclusion

Whether you are a first-time greenhouse user or a seasoned gardener who is tight on space, a portable greenhouse kit is a great option. They work well to create the best conditions for seed germination and growing sensitive plants, protecting them from frost, snow, and strong winds. You get all the benefits of growing inside a greenhouse, at a fraction of the cost of building a regular greenhouse. Plus, there is the benefit of moving it wherever you like and taking it with you if you move to a different house. Portable greenhouse kits come in a variety of shapes and sizes for both indoor and outdoor growing. They are quick and simple to set up, often without needing any tools, and they are lightweight, making them easy to move. By using them wisely, and maximizing vertical growing space, one can grow a constant supply of delicious fruits, vegetables, and gorgeous flowers, all through the year, anywhere in the world.