In the past, greenhouses could be spotted only in commercial gardening, where producers needed to come up with a controlled environment where they could grow off-season fruits and vegetables. Their dimensions were impressive and could spread over entire fields.
Now, thanks to the evolution of technology, everyone can own a greenhouse – no matter if they want a smaller or larger one. This way, they will no longer have to spend loads of money buying off-season crops from the market; they can simply grow them themselves.
Buying greenhouses now is easier than ever – which is why it’s very common now to see one in the backyard of a random neighbor.
What Is A Greenhouse?
Greenhouses – also going under the name of “glasshouse” or “hothouse” – represent an outdoor structure with walls constructed out of transparent material (usually glass), where the temperature is strictly controlled to permit the growth of the plants that are targeted for consumption or décor.
These “houses” will usually differ in sizes; they can be either very small (small enough to fit in a residential backyard), or industrial-sized. Miniature greenhouses (the ones you usually find in private gardens) are also called “cold frames.”
The insides of such a construction that has been exposed to sunlight will significantly become warmer than the temperature you can feel on the outside – therefore protecting the contents from the harshness of cold weather.
Glasshouses are also filed with equipment that is meant to control the temperature such as screening installation, lighting, heating, cooling, and they may be controlled by a computer for superior plant growth.
The newer technologies also allow growers to set the air temperature, vapor pressure deficit, and relative humidity to reduce the risk of crops failing.
History Of Greenhouses
Rome, circa year 30 AD; royal physicians have warned Tiberius, the ailing emperor, that he must consume a cucumber every day. The problem was that you could not grow them in every season – and thus started the construction of a specularium, a house in which plants could be grown.
They maintained fires outside the stone walls, warming them and sending the heat inside. The transparent roof would allow the sunlight in, and voila! You have the first greenhouse. We’re not exactly sure how accurate this cucumber story is; however, it can be found in a gardening book written half a millennium later by Thomas Hill.
When it comes to the first modern greenhouses, the Italians were the ones to set them straight. Going under the name of “giardini botanici,” or simply “botanical gardens,” these were houses in which people could grow unusual plant species brought in by explorers.
Soon enough, these houses started gaining popularity, to the point that you could see them everywhere in England and Holland. In England, these constructions were called “conservatories.” They were mainly used by aristocrats who took a liking to tropical fruits such as oranges and pineapples.
However, with how extravagant they looked, you couldn’t be exactly sure whether these greenhouses were meant only for growth or to show off to the other noble neighbors.
By the Victorian age, glass production became more massive. At this point, many people could afford such a construction – not only the kings and queens. Glasshouses were no longer only used to grow edible plants, but flowers as well.
It was a way for them to reconnect with nature; to walk among orchids, roses, ferns, and palm trees when, under normal circumstances, this would have been next to impossible.
In 1737, the first greenhouse made its way to America. Its owner was George Washington, who wanted to serve pineapples to his guests. Later on, greenhouses became more affordable and common, and they used them to grow off-season vegetables and medicinal plants.
Today, you can find small modern greenhouses everywhere. They are used for anything going from fruits to vegetables and ornamental plants.
You can even make greenhouses from a kit such as the one sold by Giantex greenhouse. Something that started as a symbol of the wealthy people can now be part of every person’s backyard.
Uses Of A Greenhouse
There are many advantages to investing in greenhouses. If you’re considering the purchase of one but aren’t completely sure if you should buy it, here are some reasons why you should:
They Extend The Growing Season
Don’t you just hate it when you can’t start growing the crops because it’s too cold outside? A greenhouse will allow you to plant your seedlings early so that when the weather gets warmer, you can already plant the next batch.
Greenhouses will also allow gardeners to grow crops even after the season is over, to further extend their harvest. So, do you feel like eating strawberries in mid-December? You might want to consider greenhouses for that.
You’ll Have Fresh Vegetables All Year
Most of the time, when winter comes, we will have to settle for dried or pickled vegetables that we set aside during the season. However, with a glasshouse (or a hothouse for colder climates) you’ll be able to grow crops all year round.
They Protect The Plants From The Harshness Of Weather
Seedling starters are always susceptible to germs and harsh weather. When left in the normal outdoor environment, they’re at the mercy of frost, heavy rain, hail and wind. The best greenhouse will help by acting as a shield against these elements.
They Protect Your Sprouts From Insects
If there’s anything that soil and airborne insects love, it’s chewing at your crops day in and day out. To protect them, you spray your plants with tons of pesticides – which you’ll eventually end up ingesting yourself after the harvest.
Now, that can’t be healthy. Greenhouses, however, will prevent pests from attacking at your plants so that all your seedlings will grow nice and healthy.
You Protect The Seedlings From Birds
Just as insects love chewing on your plants, so do birds love digging for worms – but thankfully, birds can’t pass through glass. And if they do, their last concern would be to disturb your crops, since they probably won’t live to tell the story.
Greenhouses will act as a shield for these worms so that the upper layer of the soil will not be disturbed.
You May Grow The Plants In Containers Or Straight In The Ground
Greenhouses are generally used to grow pot plants that you will eventually transfer outside when the season comes. However, you may also grow them directly in the ground, keeping them protected from airborne diseases.
They Save You Money
Fruits and vegetables that are off-season will have their prices bumped up when they can no longer be grown in the average backyard.
The best unit, however, will allow you to grow your crops in every season so that you will no longer have to overspend on your veggies or the actual installation of the greenhouse.
Greenhouses can either be built from a kit or constructed from scratch; regardless of the way you go about it, there are several design factors that you should consider before setting one up. Here are just a few of them.
Without proper ventilation, you can’t escape problems such as poor yields, slow growth, or pathogen issues.
Every horticulturist knows that for your plants to go through proper photosynthesis, you need to pick a good ventilation system that will have four crucial functions: humidity control, temperature control, air circulation, and CO2/oxygen replacement.
If you live in a colder climate, you will need to invest in a structure with a proper heating system. This can be either central or local.
A central heating system will have a boiler propped in the center. These boilers will heat the place with hot water or steam and may function on a great variety of fuels.
A local heating system, on the other hand, will be placed at the end of the glasshouse. It is the suitable option for smaller greenhouses since central heating systems are the ones usually used for commercial units.
There are plenty of foundation types, and you can use any of them to build a greenhouse.
For instance, modern foundations use concrete piers that have been attached to the framing structure. These foundations will keep your space safe from glazing and eventual snow loads.
Attached Or Freestanding
Greenhouses that are freestanding will be a great asset if you want to create a new space but are restricted by the area around the house.
You can place them anywhere around your garden – or whatever outdoor area you may have – and all you will have to do is go there now and then to tend to your crops.
An attached model, on the other hand, will be connected right off your home. While a freestanding one will need a backup heating system, the attached one will simply draw from your house, and won’t require any extra infrastructure or paths.
There is, however, the risk of having high humidity if it doesn’t have a sliding glass or good ventilation – so you may want to be careful.
Insulation is a crucial aspect, especially when we’re talking about the north and west wall; however, you may want to make sure you have insulated every wall that does not have glazing on them.
Insulation will prevent the cold from entering your facility, but will also act as a humidity controller. The best greenhouse for winter will have thick insulation that will protect your precious plants from the cold.
Beds And Paths
When designing or buying a greenhouse, you may want to consider what exactly you’ll be growing and how you plan on working on it.
Most gardeners prefer to install large paths that can accommodate wheelbarrows and carts; however, a smaller path will maximize the growing space. You may want to know exactly how much you plan on growing.
Greenhouse Covering Materials
There is a wide variety of materials that can be used as a cover, especially since there was an explosion of interest coming from both commercial and habitual gardeners.
Everyone wants to grow their own crops at all times, regardless of the season, so it’s obvious that we would want something that will not break, nor allow the cold air to get in. Here are some of the more popular options:
Glass is the standard when it comes to covering greenhouses. Our ancestors used it, and because it’s so efficient, we keep using it as well.
The chances are that the first greenhouses you saw several years ago were also constructed using hundreds of panels made of glass.
Glass can be fairly expensive and will need a sturdy structure; however, if you do it right, glass greenhouses can last up to 30 years. Furthermore, the clean glass will enable superior light transmission – so hello photosynthesis.
The only issue with glass is that it does not provide much insulation unless you construct with double or triple panels. It is also fairly expensive and difficult to replace if it gets broken by any chance.
Polycarbonate is very strong and highly lightweight. Those made for outdoor use have also received UV treatment that will prevent sunlight yellowing or deterioration, and they can stay in steady shape for at least ten years.
Polycarbonate is used by many gardeners since it’s far cheaper than glass; plus, it’s less likely to break if your kid accidentally throws a baseball at it. Gardman greenhouse models have some pretty good polycarbonate panels.
Polyethylene coverings are basically plastic, making it once more a cheap alternative to glass. However, while it’s “plastic,” they are not made the same.
This “agricultural plastic,” as it is called, is the least expensive of the coverings, and may last up to 5 or 4 years (depending on the type that you choose).
Keep in mind that, as we mentioned, no polyethylene material is the same when it comes to durability. A utility-grade one is the cheapest, but will only be used for one season. If the polyethylene has previously received UV and thermal protection, it may last up to 4 years.
Polyethylene can be turned into panels, which are longer lasting than regular polyethylene plastic. A UV-protected polyethylene panel covering may last up to 10 years, if maintained properly.
Fiberglass can be translucent or completely clear; nonetheless, it will still allow as much light into the greenhouses as glass does. It may let even more light in once the sun goes into low angles since fiberglass covering doesn’t reflect much light.
As far as manufacturers are concerned, they believe that it is one of the most durable covering materials – and therefore, they usually offer 10-year guarantees against structural failure and yellowing.
Acrylic is also among the least expensive of the coverings, and it looks pretty similar to polycarbonate – the only difference being that it scratches easier. It’s also the readiest available, and most places will cut the sheets to the desired size before selling it.
If you’re going for that clear, “showroom” look, you may want to go for vinyl. It is, however, recommended that you do not use it for the top and only stick to the sides.
The frame is just as important as a covering, so when building a hothouse for your plants, you may want to consider the qualities of the following frame materials:
Aluminum is the perfect low-maintenance ally. It does not rust, nor does it get damaged from being exposed to the elements. The only issue is that it doesn’t offer much support and that the pillars must be either very large or at least doubled up.
It still offers a pretty rigid form for polycarbonate and glass, and you can treat or paint it with any color that you wish without compromising the look or the quality.
When it comes to steel, the most used type of frame is “galvanized steel.” This one is a frame that offers durability at a low price.
They are recommended to be used as a combo with polyethylene coverings. Quictent greenhouse models are usually highly appreciated when it comes to their steel frames.
PVC plastic is also a low-cost option for those who can’t take the hassle of building such a structure. It’s lightweight, and usually very easy to assemble. It may not be as rigid as steel, but it still offers limited heat loss.
Wood looks beautiful and classy, but unless you want to build a sunroom, it won’t be of much help to you. Wood can act great as an insulator, but since humidity levels are high in greenhouses, it’s very likely that it will enter the wood and rot.
If you really want a wood frame and don’t want to go for anything else, try redwood, cedar, or a specially treated wood to which you have also applied a seal.
How To Build A Greenhouse
You’ve finally decided that you need a greenhouse in your life. Now comes the hard part: how do you build one? There’s no exact structure for building one, but still, there are some steps that are standard for every building process.
Your structure can be lifted off by strong winds, which is why you need to anchor it properly to the space that you want to set it on.
Set your foundation to the anchors. You may want to consider all your options when picking out the materials. The cheapest one is treated wood, but the choice is yours.
Build the walls of your structure with the frame materials of your choice. Keep in mind that certain coverings are only compatible with certain wood frames, so you may want to do your research on that.
Build the roof. Be careful on the angle and the orientation, since it needs to catch as much light as possible.
Choose the covering. It can be anything from glass to polyethylene, vinyl, and polycarbonate.
Decide on an interior design and a finishing. Here you may want to keep the ventilation system and heating in mind. Depending on the size of your structure, you may want to go for a central or a local heating system.
Decide on the beds and the shelving. Do you want raised beds or regular ones? You may also want to build some shelves if you plan to store potted plants.
The advantage of building greenhouses is that you are allowed to be creative. Choose the materials that work best for you and let your imagination flow. If you want to build a king canopy greenhouse, you are free to do so.
Greenhouse Maintenance And Cleaning
To ensure that there won’t be any problems, greenhouses will need proper maintenance. Here are some tips that you may want to consider:
It can be maddening to take care of a greenhouse; but if you perform the maintenance at the right time, you’ll be saving yourself a lot of trouble.
Greenhouses have been around for a while. Without them, we wouldn’t be able to satiate our craving for off-season fruits or veggies.
While they may need particular attention during the building process, it will surely be worth it when you finally dig into your harvest. If you’re not sure what to choose, you can always check our buying guide.