Updated at: 15-03-2023 - By: Sienna Lewis

Knowing how to clean and sterilize, monitor, inspect, and prevent damages to your mini greenhouse is essential to its longevity and the success of your garden. Mini-greenhouse efficiency and effectiveness are directly tied to the care and maintenance that you put into it. In the same way that learning how to start plants in a miniature greenhouse is a necessary first step before planting, so is learning how to care for a greenhouse.

Mini greenhouse maintenance is easier and faster to complete due to its diminutive size. This, however, does not imply that a half-hearted effort to complete the steps outlined here will be sufficient. The University of Massachusetts Amherst reports that keeping the greenhouse clean can help prevent the spread of disease.

What is a mini greenhouse?

Mini greenhouse is an umbrella term for many different commercial and DIY options. In most cases, their footprint is smaller than 3 square meters (roughly 10 square feet), regardless of how wide, tall, deep, or shallow it is. Mini greenhouses are typically placed in a semipermanent location, in contrast to the more portable cold frames. With the right knowledge and maintenance, you can use them to grow plants all year long. You can start seedlings earlier in the year, and you can overwinter your plants more successfully.
With the addition of heater elements and grow lights, the growing season can be boosted and extended with some models of mini greenhouses.

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Complete Guide For How To Take Care Of Mini Greenhouse

Clean and sterilize

As was previously mentioned, one of the simplest ways to take care of your mini greenhouse is to clean it. Although it is a clear obligation, some gardeners fail to carry it out unless they are reminded of the task by an obvious sign. If you want to rid yourself of pests and diseases, you should make cleaning and sterilizing a regular part of your routine.

Cleaning, according to the University of Missouri, entails getting rid of weeds, vacuuming up dirt and other debris like potting soil, and using cleaning products to get rid of algae, dirt, and fertilizer. Alternatively, you can use water and eco-friendly soap, but you’ll still need to pay close attention to the residues.

A greenhouse needs to be sterilized or sanitized after cleaning. In the compact greenhouse, you can pick between various solvents like alcohol, bleach, hydrogen dioxide, and quaternary ammonium chloride salt. However, due to their flammability, proper ventilation is required.

For the sake of the plants and the gardeners, be sure to strictly adhere to the directions on each chemical used for cleaning.

Careful monitoring, inspection, and prevention

Because of its compact size, the miniature greenhouse facilitates rapid and thorough daily monitoring. The greenhouse gardener must keep all parts of the structure in constant check so that any problems can be dealt with as soon as they appear. You’ll save time cleaning and maintaining, and you can plan ahead to avoid surprises.

Keep an eye on your plants outside of the mini greenhouse as well. The spread of diseases and pest infestations can be stopped in their tracks if affected plants are removed promptly. This is also the point where remembering to take precautions is crucial.

Inattention to detail may be responsible for the proliferation of weeds in the greenhouse. This includes inspecting and cleaning all items before bringing them in for reuse. When dealing with pests, it is important to always check the most recently added plants first, and to add beneficial insects that would feed on pests.

Maintain internal conditions

Maintaining the miniature greenhouse entails more than just keeping it clean, inspecting it, and making sure nothing is broken. The mini greenhouse can benefit from regular indoor environmental service as well. A poorly functioning ventilation system, for instance, is not only bad for the plants, but it can also lead to condensation and structural damage in a greenhouse.

Regarding air flow, the weather can cause problems for the mini greenhouse’s doors and windows. You may discover that they don’t shut completely, which can have an effect on the indoor air quality. Also, holes and tears in the screens could necessitate mending or replacing them.

Equipment like heaters and fans used to keep the mini greenhouse at a comfortable temperature are also crucial. Always make sure to check for corrosion or buildup of dirt to save yourself time and money in the long run. Check the fuel levels of your heaters and avoid drenching your fans in oil.

Finally, the watering system is another component of the greenhouse that requires routine maintenance. The lines, hoses, and cracks are often disregarded by gardeners. Over time, they can get dirty, leak, or become clogged; to avoid costly repairs or replacement, it’s best to catch these problems early on.

Why Consider A Mini Greenhouse?

The mini greenhouse will do you a lot of good if you take care of it. This setup is perfect for delaying harvests, protecting young plants from harsh elements, and extending the growing season. This may sound like a lot of work, but when compared to gardening in the open air, the work involved in maintaining a mini greenhouse is actually quite small.

How to choose a mini greenhouse?

Mini greenhouses range in price from around £50 – £75 for a small metal frame and a simple plastic cover with a zip up cover to nearly £1000 for a premium mini greenhouse. The latter are usually made of glass and hardwood or aluminum. Thus, why spend more?
The old adage that you “pay for what you get” holds true in this case as well. The polythene cover on the cheaper models usually only lasts one or two seasons before it is too worn out to be of any use, and they are easily damaged by strong winds and snow. That could lead to you wasting time and energy chasing the clear tent around the garden while your plants are inside of it.
Therefore, the product’s design, as well as its aesthetics, materials, and quality, are crucial. Solid hardwood frames are beautiful and long-lasting, provided the wood has been properly seasoned. As greenhouses made from cheaper wood may warp over time, it’s important to inspect the joints before committing to their use. Aluminium is strong, rust-proof, and long-lasting; additionally, if the aluminium is thick enough, they are extremely sturdy. Aluminum frameworks can also have a beautiful, long-lasting powder coating applied to the outside. Before making a final choice, make sure you have thoroughly viewed all of the images and read all of the product details.

Mini greenhouse sizes

Mini greenhouses are appealing because they allow gardeners to make the most out of a constrained amount of outdoor space. This usually entails considering taller models with tiers of staging or shelves to add height. Models with hinged doors require additional room to open, so you should stay away from them if at all possible.
The rule of thumb is to order a bigger size rather than a smaller one if you’re not sure. Be critical of the amount of growth and the amount of space needed; many people complain that they don’t have enough space to grow in. It’s easier to make room for new plants if the greenhouse isn’t completely full.

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What glazing should I use?

Putting aside greenhouses covered in inexpensive plastic or thin acrylic sheets, you can choose between polycarbonate and glass, each of which has its benefits and drawbacks.




The transmission of light is very good.

Holds up well in the snow and wind.

Protective when laminated with safety glass


Conspicuously difficult to sub in

The cost increases

lacking in insulating qualities


Excellent transparency

With good insulating qualities

Maintains its shape even in heavy winds and snow if constructed properly.

Super secure

Supple to swap out

Poorer plant perception

Typically, a 10 year guarantee is given.


No matter the size of your greenhouse, proper ventilation is essential. Many people invest in a greenhouse with the express purpose of protecting their plants from extremes of temperature, both summer and winter. The key to success is adequate ventilation, which can be ensured by allowing air to flow through the space and thereby preventing the growth of mold and fungi.
It’s best to steer clear of greenhouses with front-hinged doors that can’t be locked in place. With no way to keep them from slamming in even the slightest breeze, trays and pots can be easily knocked over. Greenhouses with opening lids that aren’t securely fastened should be avoided as well, as they can be damaged by flying debris in high winds. The risk of breaking the glass panes is especially high in greenhouses.

 Where to place a mini greenhouse?

Where do we even begin? Mini greenhouses are extremely versatile, allowing for placement on a wide range of surfaces, including soil, raised beds, decking, balconies, or even a hard surface like a patio. The decision is entirely up to you. If yours is going to be more than about 2.5 feet tall, you should have a way of securing it to the ground or to something solid that you’ve already chosen to place it on.
In addition, the direction in which your garden faces the sun has a significant impact on the crops you are able to successfully cultivate. Here, we’re referring to the orientation of your miniature greenhouse’s entrance.
Even though a south-facing greenhouse is ideal, keep in mind that it will likely become very hot in late spring and throughout the summer.
This is a good option for many people because it allows you to take advantage of the sun all year long without having to sit in the heat of the midday sun during the spring and summer.
North Positioned here, later in the season, young plants will benefit from being shielded from the sun’s rays. Unfortunately, tomato and pepper plants require direct sunlight and cannot be grown here. These can be started in a mini greenhouse or grow system with a north-facing window, and then moved to a sunny location once the threat of frost has passed.

How do I keep a mini greenhouse cool?

Ventilation, as we have already established, is crucial to the health of any greenhouse. By maintaining a healthy temperature for your plants and preventing the spread of harmful diseases like mold and fungus, good ventilation is essential.
Some more expensive miniature greenhouses have temperature-sensitive louvers or moving lids. You can easily adjust the activation temperature, and once activated, they will either release hot air through the top vents or admit cooler air through the bottom ones.
The majority of small greenhouses also feature a door system. On warmer days, you can let in some fresh air by opening the greenhouse’s doors; just make sure they stay in place in the wind.

In the dead of winter, how do you heat a small greenhouse?

In spite of the fact that on cloudless winter days the sun can warm your greenhouse, there are still a number of methods that can be used to increase the temperature. During the colder months, a small thermal store installed inside the greenhouse can be helpful if you have the room for it. A small, dark tank of water that soaks up the sun all day and radiates the heat out at night would work well. If you’re looking for similar examples, try this link. http://greenhousegarden.com/thermal-massheat-storage
Traditional greenhouse heaters, if compact enough, could also work; these typically come as paraffin or electric heaters made specifically for the greenhouse environment. Promotion for them is extensive. Heaters, especially electric ones, can be dangerous in a greenhouse; only use those designed for that purpose. Make sure it produces an appropriate amount of heat for the area you intend to use it in, or you risk accidentally overcooking your plants.
Soil heaters and heated seed trays are just two examples of the specialized heating systems that can be found in some greenhouses.

Do mini greenhouses protect from frost?

The degree to which frost damage is prevented depends on the type of protection afforded the plant. However, extremely cold weather can occur even in the UK. The Met Office reports that on 30 December 1995, at Altnaharra, and on 10 January 1982, at Braemar, the temperature dropped to a record-breaking -27.2 degrees Celsius.
There’s no doubt that in these conditions, plants inside an unheated building will struggle. The frost hardiness of a plant depends on the type of plant grown and its ability to withstand temperatures ranging from mild (-0.1C to -3.5C) to extremely cold (below 11.5C). The RHS and Garden Organic both have helpful guides on frost hardiness in plants and how to garden in the face of frost.
In any case, placing an unheated mini greenhouse on, or next to, a wall or patio will provide some front protection for your plants. You can use limited heating to keep the plants just above that frosty temperature, but it’s important to consider the type of plant you’re trying to overwinter as well as the location of your mini greenhouse.


Where to find good growing information for a mini greenhouse?

Web forums, Facebook groups, and regular books are just some of the many available resources. To learn more about greenhouse cultivation, we advise reading Dr. Hessayon’s book.

What can I grow in my Harvst mini-greenhouse?

Spinach, chard, spring onions, kale, salad leaves, and rocket are all examples of low-growing greens that thrive in more artificially warm conditions. You can do everything in a microgreenhouse that you could do in a full-sized greenhouse, including growing annual, semiannual, and perennial flowers from seed and propagating them from cuttings. When the plants start to grow, keep an eye on them. Tomatoes and other plants of similar height may outgrow the Terrace but thrive in the Yard.

How do I put things in it? Pots? Soil? What?

Most people will use soil to fill their box (possibly in a raised bed), but deep pots or containers are fine too. Whatever you’re cultivating will determine the answer. Tomatoes are sometimes grown in grow bags that can be placed directly on concrete. For the upper levels, use deep seed trays, and for the lower levels, use grow tubs.

Where should it be in my garden – sun? shade? mix of both?

When possible, locate your Harvst greenhouse where it will receive ample sunlight and warmth. It will throw open and stay relatively cool in the summer, but in the winter, you’ll want to keep in as much light and heat as possible. Either directly on the ground with at least 12″ of soil underneath it for the roots, or on concrete (in a raised bed at least 12″ deep, if possible, or in deep containers). If you live in an area with high wind, it is important that you anchor your mini-greenhouse to the ground, a wall, or a fence.

What can I put on the shelf?

You can grow smaller plants like salad, spinach, and more to full size on these shelves, making them ideal for storing seedling trays or propagation boxes.

Can I get a Harvst ‘grow kit’ – like seeds, soil, instructions for my first Harvst?

Sorry, but we haven’t gotten around to it yet. Keep an eye out.

How much soil do I need?

Approximately 500 kilograms of soil will be needed to fill a full-size Harvst greenhouse to a depth of 20 centimeters.

Greenhouses in the desert: Are they useful?

Do I need special skills or tools to build it?

No, I’m only using what came with the kit.

Isn’t an electrician needed to run power in the garden?

All of the gear we rent out has been checked for safety. Low voltage, which is much safer than mains voltage, is used to power the Harvst greenhouse interior. Since we are not directly connected to the mains, our heating and lighting systems do not have the same power as they would if they were, but low voltage has the advantage of being both safe and convenient.


A mini greenhouse allows you to grow plants and fresh crops in a small garden without worrying about the effects of weather extremes. However, you need to know how to properly care for a mini greenhouse in order for it to be useful and practical. A mini greenhouse is convenient not only because of its small size, but also because of the ease and speed with which it can be cared for.

Cleaning and sterilizing, monitoring, inspecting, preventing, and maintaining your mini greenhouse will keep it in good shape. Including these things on a regular basis in your routine will improve the mini greenhouse’s efficiency. By preventing it from breaking, you’re extending its useful life.

What you’re doing now to care will end up saving you time and money in the long run. Having access to seasonal fruits and vegetables throughout the year is a worthwhile reward for your labor.