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Are Mini Plastic Greenhouses Any Good? What You Must Know

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Mini-plastic greenhouses are increasing in popularity. When I began researching whether mini plastic greenhouses are suitable, I found valuable and exciting information on this topic. In the following article, I’ll share my findings with you.

Mini-plastic greenhouses are indeed good additions to a garden or allotment, and they are especially effective at seed starting and plant cloning. Another advantage of using mini-plastic greenhouses is that they are mobile and take up little space.

Many gardeners are working with limited space and are turning to the best portable greenhouse alternative methods. For some people, it’s not possible to fit a full-sized glass greenhouse in their outdoor area. These traditional greenhouses require plenty of space and are difficult to transport into some gardens.

plastic green greenhouse

Thankfully, a mini plastic greenhouse provides a valuable and practical alternative. These smaller units are good at many aspects of gardening, whether you need a place to start your seeds or to nurture clones and keep the lineage of your favorite plants alive.

It’s impossible to grow as many plants in a mini plastic greenhouse as in a full-sized glass one, but they are a great way to produce small numbers if you have limited space. You can utilize a pop-up greenhouse.

The advantages of mini plastic greenhouses

Mini-plastic greenhouses are an excellent alternative to full-sized glass greenhouses. They vary in dimensions but usually have a base of less than 10 square feet.

They are trendy among gardeners with limited space available, who want a greenhouse to start their seedlings early, or who need high humidity to propagate certain plants when used indoors.

One of the good aspects of mini-plastic greenhouses is that they are pretty easy to make. Indeed, there are plenty of commercially made options out there to choose from, but gardeners can also construct their own.

It’s as simple as building a makeshift frame out of wire and fitting it with a plastic cover. If you would instead purchase one, they’re not too expensive, especially when compared to larger-sized glass greenhouses.

As I mentioned earlier in this article, perhaps the thing that mini-plastic greenhouses are most useful for is seed starting.

This is the case, especially if the mini plastic greenhouse has a singular shelf rather than multiple.

They are so good at seed starting that they provide plenty of sunlight while protecting the roots from the elements. Amorphous plastics are transparent materials that let most sunlight through to the sources.

The mini greenhouse stops solid winds or rain from disturbing the seeds and prevents unwanted pests from potentially harming them.

Another purpose that mini-plastic greenhouses are suitable for is cloning plants already in your garden, and plastic is an excellent material for trapping humidity.

Cuttings require humid conditions to thrive, so mini plastic greenhouses are great environments for improving the chances of successfully taking.

When hardening young plants, mini-plastic greenhouses are also a good choice.

small plastic greenhouse

By hardening, I am referring to allowing young plants to benefit from as much sunlight as possible while protecting them from heavy rain and strong winds.

The tiny seedlings can be adversely affected when grown indoors because the amount of light they are exposed to is always limited.

Mini-plastic greenhouses are ideal because they are mobile enough to be moved around the garden to maximize the young plant’s exposure to natural light and allow drainage.

The disadvantages of mini plastic greenhouses

To establish whether mini-plastic greenhouses are suitable, we must examine both sides of the argument.

As I’ve discussed, there are several reasons that they are a worthy addition to your garden.

However, as with all equipment, there are some negative aspects to be aware of.

Gardeners’ main issue when using mini plastic greenhouses is that they are susceptible to being damaged by heavy wind.

This can cause the plastic covers to tear in some cases, especially around the greenhouse door. Securing them properly is key to surviving windy weather, and Ground-fixing pegs can be used to achieve this.

An excellent way to combat this is by positioning the mini plastic greenhouse somewhere that doesn’t get too much wind, or if this is not possible, at least position the door side away from the most common wind direction.

Another solution to the prospect of wind damage is reinforcing your mini-plastic greenhouse.

This can be done using ground anchors or weighing down with small rocks and bricks. The materials that the frame is constructed of will also impact the mini greenhouse’s resistance.

Galvanized frames are the most robust option, but their price reflects this.

Other than potential damage from wind, there aren’t any other disadvantages to using mini-plastic greenhouses. Their versatility, convenience, and low-cost fare outweigh any minor pitfalls.

As long as you consider that they are under threat of being broken by extreme weather conditions, you can plan accordingly to prevent this from happening.

Another thing to consider when using a mini plastic greenhouse is the presence of rainwater. If the rain collects on the mini greenhouse, this will cause it to become misshapen and potentially destroy the structure.

It’s, therefore, essential to shape the roof of your mini plastic greenhouse so that water can run off it quickly.

The durability of a small plastic greenhouse will depend significantly on how it is built. The poles used to make the greenhouse structure must be sturdy and made from solid materials.

This is especially important if you get a lot of wind in your garden.

What are mini plastic greenhouses suitable for growing?

Mini plastic greenhouses are particularly useful for hardening-off young plants in the spring and early summer months.

Vegetables and half-hard annual growers are well suited to the benefits of a more miniature greenhouse. They enjoy the middle ground between a full-sized greenhouse and a garden’s more extreme weather conditions.

More miniature plastic greenhouses also provide some much-needed warmth for tender summertime growers.

The heat built within the plastic greenhouse speeds up the ripening process and can help the crop grow larger. Tomatoes, chilies, and aubergines are summer crops that would suit a mini plastic greenhouse.

Plastic greenhouses generally help heat-loving plants to grow. This is because they retain warmth from sunlight for long periods of the day.

However, their effectiveness is not limited to full-sun annuals or easy-growing vegetables.

If a gardener is precise and intentionally creates a suitable microclimate within a mini plastic greenhouse, there’s no limit to what you can grow.

A range of fruits, veggies, and annuals can be nurtured, but more experimental growers like cacti or orchids are possible if the proper measures are taken.

You can also use mini plastic greenhouses for seed starting indoors. The extra protection from the elements used indoors will ensure the seeds aren’t damaged.

It’s essential to place them somewhere that gets frequent sunlight exposure throughout the day; then, when they start to grow, you can transfer them outside.

Starting seeds is much easier in a humid environment. You can use fluorescent lights and heat pads to create the perfect setting for an indoor mini greenhouse.

If your greenhouse has a zipper to open the door, it’s essential to remember to open it on a hot sunny day; otherwise, the plants may overheat and be irreparably damaged.

Mini Plastic Greenhouses vs. Glass Greenhouses

The majority of greenhouses are made with glass panes. The reason that glass is so popular is that it lets almost all of the sunlight through and is considered durable enough to withstand extreme weather’s inevitable rigors.

8 x 6 greenhouse

Compared to mini-plastic greenhouses, the downside to glass greenhouses is that they are much bulkier, harder to set up, more costly to purchase, and more hassle to replace if a plane of glass gets smashed.

Mini-plastic greenhouses, notably polycarbonate varieties, have many benefits over their glass alternatives regarding convenience and performance.

Some garden experts predict that polycarbonate plastic will overtake glass as the primary material used for greenhouses. Let’s look at the main reasons this is likely to be the case.

1) Longevity

Mini plastic greenhouses made from polycarbonate material will last longer than glass. Surprisingly, it’s a stronger material and can withstand more wear and tear before breaking.

Because plastic is lighter than glass, there’s less chance of getting damaged when it is handled or moved.

Replacing parts of a mini plastic greenhouse is a straightforward process, whereas glass panes can be difficult.

It’s also well within an average gardener’s capabilities to construct or set up a mini plastic greenhouse. Still, a glass one usually needs help from a professional due to the complexity of fitting the windows to the frame.

2) Insulation

Mini-plastic greenhouses are great at insulation and retaining warm temperatures.

Polycarbonate plastic is particularly good at this. Less heat is lost through plastic material than glass.

This keeps the average temperature of a plastic greenhouse consistently higher, especially considering the small size. Keeping a mini greenhouse warm is essential to help plants thrive and grow to their maximum size potential.  

Heat retention is perhaps the best quality of a mini plastic greenhouse.

3) Shatter-proof

Small plastic greenhouses are in no danger of being shattered. Unlike glass alternatives, they can withstand impact from other objects without damage.

plastic greenhouse

This is a valuable benefit of mini plastic greenhouses for people whose garden is also part-time playground for youngsters. The risk of injury is significantly reduced when compared to larger glass greenhouses.

4) Light

Plastic is a thicker material than glass, so another benefit is that it spreads light evenly.

This process is known as light diffusion. The plastic diffuses the sunlight equally throughout the mini greenhouse, so if you have multiple plants growing there, none will be deprived.

Some plastics also naturally block harmful radiation such as ultraviolet, so the contents of a mini greenhouse would be well protected.

5) Longer Growing Season

The benefits of mini plastic greenhouses all accumulate to impact the growing season’s length positively.

Using them, you get better results from your plants, vegetables, and fruits all year round. This ultimately saves a gardener time, money, and effort.

Due to the mobility of mini-plastic greenhouses, you can constantly move them to thrive in the best positions.

The best plastics for mini-greenhouses

We’ve established that mini-plastic greenhouses are great additions to a garden, but it’s important to note that the type of plastic you use will significantly impact the structure’s effectiveness.

Here’s a breakdown of the different varieties and their benefits.

Polyethene is considered the industry standard for making mini-plastic greenhouses.

It’s a reasonably cheap material that is readily available and easily repairable if it breaks.

Polyethene comes in many different grades, some well suited to general utilities and others specifically for agricultural use.

The only negative aspect of polyethylene is that it lacks the durability of other plastic types.

It will likely need repairing now and then, which is a hassle most gardeners would like to avoid.

The low cost makes this less of a problem, but it uses more time and effort.

Polycarbonate is a little more expensive than polyethylene but is much more durable and robust. It’s made from a composite of sheets, and the multiple layers make it great for insulation.

It’s also a flexible type of plastic and lets in a reasonable amount of sunlight.

small plastic greenhouse

The final option is polyvinyl carbonate, or PVC, as it is commonly known. Many gardeners use PVC for their mini-greenhouses due mainly to its exceptional durability.

It can last many years without needing to be repaired, which is reflected in the cost. It usually comes in short sizes, which makes it perfect for constructing a mini greenhouse.  


To conclude, yes, mini-plastic greenhouses are suitable for many purposes, and they provide a convenient alternative to bulkier glass greenhouses if you have limited space in your garden.

They are also much lighter, easy to move around, and more affordable.

However, the type of plastic you use to make the mini greenhouse will affect its ability to grow plants. And it would be best if you were wary of windy weather.

Small plastic greenhouses are very effective for seed starting and protecting young growers. You can use them indoors and outdoors, provided the structure is sturdy; there’s no reason why they couldn’t last for a few years.

Humidity and heat retention are also two great qualities of mini-plastic greenhouses. The small, compact size and the multiple layers of material mean that the sun’s heat is absorbed well and stays within the greenhouse for a decent amount of time.

It’s important to air out the greenhouse on a sweltering day.


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