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Building a Backyard Greenhouse


Building a Backyard Greenhouse

There was a time when almost every large home had a greenhouse. Those days have passed, but plenty of people still build them every year. Even a small property can support a respectable greenhouse and there are plenty of reasons why people would choose to build a greenhouse over planting a traditional garden.


Why Greenhouses?

The greatest advantage that a greenhouse offers is control over the growth environment of the plants. Greenhouses are much warmer than the environment around them, which gives gardeners a chance to grow plants that would normally die from the cold outside the greenhouse. A skilled gardener can calibrate the internal temperature very precisely, so they can also ensure that the plants are at the optimal temperature for growth. This makes greenhouses a useful tool—even for gardeners who are growing native plants that can survive without one.


They also offer some protection from environmental hazards, such as pests. Most wild animals that can eat the plants in a garden will be unable to enter the greenhouse, assuming that there are no gaps in its construction. The structure will also offer some shelter from mold spores, insects, and other potential hazards. It isn’t enough to guarantee that the plants will be safe, but it does increase the odd of the plants surviving until the harvest.


Selecting the Site

There are a few decisions that a homeowner needs to make before they can get started on their greenhouse. The first is the site where they intend to build it. The precise location is more important than many people believe, since greenhouses are still dependent on natural light to sustain their plants. In most cases, it’s best to build the greenhouse near the southern end of the property to ensure that it gets as much light as possible. The greenhouse also needs to be kept away from tall trees and anything else that might cast shade on it.


Ease of use will also help to decide the location. It’s best to keep the greenhouse close to a source of water. That minimizes the amount of work that the builder needs to do in order to connect a hose to it, or the amount of time that a gardener spends hauling water to an unconnected greenhouse. Keeping it close to the home is also desirable on most large properties so that the gardener doesn’t need to spend too long walking out to work in the greenhouse.


Big or Small?

Size is an important consideration. Most backyard greenhouses will be fairly small, both due to lack of space and because plants can be planted quite densely in a greenhouse. Smaller also means cheaper, which is valuable for most homeowners.


On the other hand, larger greenhouses tend to have more stable temperatures, so they’re easier for novice gardeners to manage. Striking a balance between those factors is crucial, and most people who are new to greenhouses should choose a structure of moderate size.


Picking Plans

The final part of the preparation is choosing the design. Most people aren’t qualified to design their own greenhouse, but there are plenty of free designs available to choose from online. Gardeners should keep their needs and their construction skills in mind when choosing to make sure they select an appropriate design.


Preparing Materials

It’s best to start the project by gathering all of the necessary tools and materials, to make sure that there are no unexpected and irritating delays during construction due to missing parts. Most designs will come with a full list, but in some cases the builder will need to produce their own based on the instructions. Every plan is unique, but there are some things that will show up in the majority of them:

  • Glass or plastic panes, which allow light to enter the greenhouse while preventing warm air from escaping.

  • A frame material, which is usually wood or metal, to provide structural support for the glass.

  • Most, but not all, designs also call for a flooring material. Some will also need a constructed foundation, although that is not universal.

  • Most greenhouses will need a single door, which can either be a sliding door or mounted on hinges.

  • Hinges, screws and other miscellaneous items are always required. It’s important to be sure to purchase the right sizes, which should be listed in the plans.

  • In some cases, the builder will have the choice of buying wooden components that have already been cut to size or buying lumber and cutting it down independently. Raw lumber is usually much cheaper, but only for people who can do the work without making mistakes that waste the wood. Confident builders should consider that option, but it’s usually quicker, easier, and safer for inexperienced workers to have professionals cut the materials to specifications.

Assembling the Greenhouse

If the design provides assembly instructions, it’s best to follow them to the letter. If not, we have a general guide to construction that will work for most designs. A small number of plans call for artificial heaters or other supporting components, but are so uncommon that they are not included in this process. When in doubt, builders should look for guidance in the design that calls for them or seek out specific advice about that particular component.


Always start by preparing the site. Make sure that it’s flat, unless the design specifically calls for an uneven surface. A slight slope leading away from the greenhouse is often desirable for drainage. Once the site is ready, builders should install the foundation if their design calls for one.


The next step is the floor. Some designs call for insulation around the flooring, which needs to be added at this stage. After this, the greenhouse’s frame should be assembled. The glass and any wall panels should be left out at this stage to make the rest of the construction easier.


Once the frame is ready—check over the entire building for errors. It’s much easier to notice and fix them at this stage than once everything else has been installed.

The final steps are to install the siding and roof of the greenhouse, then the doors and any other minor components.

Create a garden EXACTLY how you want it by building your own backyard greenhouse! Regardless of the greenhouse design you choose, Doug Ashy has all of the supplies and materials you need—with experts that’ll help you every step of the way.

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