When deciding where to position your greenhouse, the main question to ask is which direction should my greenhouse face.
If you want to grow plants year-round and you live in an area that gets cold? If so, then you will want to position your greenhouse so that the roof’s ridge sits east to west. This lets you maximize the sunlight during the dark days of winter.
If you do not plan on growing plants during the winter months and you will only be using the greenhouse in the spring and summer, then you’ll want to ensure that the greenhouse ridge runs north to south so that both portions of your greenhouse receive ample sunlight.
If you are building a lean-to greenhouse, then the best position would be the one where it is facing south. Have the supporting wall constructed on the north side.
Now that you know which direction your greenhouse should be facing, let’s address the second question – where to place it. Everyone’s situation is unique and there are many deciding factors involved in the placement. A lot of the decision hinges on where you are located.
When I made the decision to build my first greenhouse, I was living in Central Oregon which is the High Desert. The sun shines almost every day in the region, but the winters are cold with heavy snowfall and the area regularly experiences windstorms. I wanted my greenhouse protected from the wind and snowfall, but I also wanted to make use of all the available sunlight that I could.
But let’s look at the deciding factors.
Considerations for Type of Greenhouse
A detached greenhouse is an independent structure that can be placed anywhere. They tend to look like small houses or buildings. Usually, they will have either glass or polycarbonate panels.
A hoop house is usually affixed with plastic and has curved purlins where the plastic is stretched from the bottom and over the top. This form of a greenhouse does not require a foundation. It can be large or small and form a tunnel-type structure when complete. A hoop house is often favored in areas with hot temperatures. You can roll up the sides to create airflow and improve ventilation.
Determining the type of greenhouse that you will construct will help you decide where to place the structure.
Consider Your Garden’s Unique Conditions
Every garden is unique. You want to place your greenhouse in an area that gives the plants and seedlings a headstart for sturdy growth. Ideally, your greenhouse should be positioned in an area of the yard that receives ample sunlight but also has some protection from frost pockets, heavy snow load, and excessive wind.
Avoid locating your greenhouse in any area of the property that has a pileup of surface water due to poor drainage.
If your land is made up of rolling hills, avoid placing the greenhouse in the hollow because warm air rises and chilly air remains close to the ground. The hollow takes longer to heat up and is prone to frost on a freezing day. Instead, consider placing your greenhouse on the hill to create a more even temperature and avoid unwanted cold pockets.
The area where the structure will sit needs to be level. Ideally, it should also have good soil, or you will need to bring in rich soil. If you intend on growing in raised beds, containers, pots, or grow bags then the soil in the area where the greenhouse sits will not matter as much.
Placing the Greenhouse Near a House
If you live in a cold climate, you might want to place your greenhouse next to your home’s door, window, or basement so that you can heat the interior by opening your house up to the greenhouse. One consideration is that heating the greenhouse will increase your home’s energy consumption, so you’ll experience higher home heating expenses.
Steer Clear of Tree
When I constructed my greenhouse, I positioned it away from trees because I knew that the snow load often snapped the tree branches which would then become potential torpedoes that would damage my greenhouse. Also, I wanted to welcome the sun during the frosty winter days so I could garden year-round in the confines of my greenhouse.
If you position your greenhouse under a large canopy of trees, then the tree’s branches and foliage will filter a significant amount of sunlight from your greenhouse which will cause your plants to suffer from poor growth.
Trees are also messy. During the spring, some produce a great deal of pollen which will stain the surface of your greenhouse, so you are constantly cleaning away the sticky yellowish-orange substance. Also, birds favor trees and will do their business perched on the tree’s branches so your greenhouse will quickly become speckled by messy bird droppings.
During periods of high wind, the branches of a tree can easily snap off and damage your structure by smashing through the plastic or glass panes.
The following foliage in the fall can also make a mess. You’ll have to continually brush the leaves off your greenhouse panels, or they will obliterate the sunlight from your plants.
If you are trying to decide where to place your greenhouse and you live in a windy area then remember that trees function as a windbreak, but you should ensure they are a suitable distance from your structure. You do not want the trees to cause damage or block sunlight. Also, you can position your greenhouse by a high wall or a tall hedge to also act as an effective barrier. It will help protect your greenhouse from windchill which can plunge the temperature inside.
Pick Level Ground
You do not want to build your greenhouse on unlevel ground. For ultimate stability, ensure that the ground is level, or the greenhouse will be tweaked so the doors or the windows do not open or operate correctly. You want your greenhouse level and square so it lasts for years and can easily withstand a storm.
The level ground will make the entire construction process easier. Especially if you want to install raised planting beds.
Provide a Little Space
Yes, you’ll want to shelter your greenhouse from the brutally cold winds, so your plants stay warm, but you still need to provide a little space for the perimeter around your greenhouse. Ideally, give your greenhouse at least three feet of space for breathing room. If you need to replace panels or do a little upkeep to the structure you have enough space.
If you build your greenhouse so it is only inches from a fence line or some other structure, then you’ll have a demanding time cleaning the exterior of the greenhouse (it can easily become discolored and develop green algae growth) and you won’t be able to perform any needed repairs.
Even if you have ample land that would support a greenhouse nicely for sun exposure, you still must consider other things such as accessibility to water and power so you can run fans and a heater. I decided to place my greenhouse close to my home due to the amenities nearby. In such a location, I was able to collect water in rain a lot from the gutter system on my house. I would then use the rainwater to water my greenhouse plants on occasion.
I liked the position close to my house because I could easily cut fresh herbs and veggies for use in my kitchen without having to travel a great distance across the yard. Also, it’s easier during the winter months because I don’t have to trudge through the snow for a long distance.
Locating the greenhouse close to my backdoor also gave me access to power so I could run heaters during the winter months and fans in the heat of summer. I liked having it only a few steps from my backdoor. It was easily accessible and quickly became a favored retreat.
Think About Child Safety
Do you have young children who regularly play in your yard? If so, you’ll want to position your greenhouse far away from the play area, so balls do not get thrown, kicked, or hit into the greenhouse. Also, if you have a glass greenhouse, a child could easily be running and accidentally fall into the greenhouse exterior. Ideally, if you have children then you should consider using polycarbonate panels in place of glass.