This is one of the questions we receive most often, yet it's a step many gardeners tend to rush. They just put the greenhouse wherever there's space, thinking they'll figure it out later. And then, a few months later, they realize their tomatoes are growing crooked, the greenhouse is in the shade by 3 PM in winter, or it takes the full force of the wind with every storm.
Choosing the right location for your polycarbonate greenhouse is perhaps the most important decision in the entire project. Even before thinking about seeds, substrate, or watering. Because a poorly placed greenhouse, no matter how good it is, will never reach its full potential.
In this article, we explain everything you need to know to install your greenhouse in the right spot, with maximum sun, minimum constraints, and the best possible conditions for your crops. We cover orientation, shadows, terrain topography, wind exposure, and a few special cases that deserve attention. ☀️🌿
Happy reading, and above all, take the time to observe your garden before putting in the first screw. You won't regret it. 🧑🌾
Why location is so crucial for a polycarbonate greenhouse 💡
A polycarbonate greenhouse acts like a solar collector. The cellular panels let light in, which then converts into heat inside. The more light your greenhouse captures, the higher the internal temperature, and the more vigorously your plants grow.
Conversely, a greenhouse half in the shade loses much of its purpose. It will be colder, plants will grow slower, and you'll struggle to cultivate light-demanding species like tomatoes, peppers, or cucumbers.
What light specifically brings to your crops:
- ☀️ Photosynthesis: plants produce energy through light. Without sufficient light, growth slows significantly.
- 🌡️ Heat: solar light naturally heats the inside of the greenhouse. In winter, every ray of captured sunlight is precious.
- 💧 Humidity regulation: a well-exposed greenhouse dries faster after watering, which limits fungal diseases.
- 🌱 Fruit quality: light directly influences sugar and flavor content. A tomato grown in a well-exposed greenhouse is often much tastier.
That's why finding the best location is not an option. It's fundamental. 🏡
The ideal orientation for a greenhouse in the garden ☀️
This is the first parameter to master, and also the one that generates the most questions. Which direction should my greenhouse face? South? East? Along the east-west axis?
The answer depends on two factors: the shape of your greenhouse and your main objective (summer, winter, year-round).
South-facing greenhouse: the classic choice 🌅
For the vast majority of French gardens, orienting the main facade of the greenhouse towards the south is the solution that maximizes sunlight throughout the year. As the sun is lower in winter on the south side, a south-facing greenhouse captures maximum rays during the coldest months, when every degree counts.
This is particularly important if you are growing in winter or starting early seedlings in January-February.
Advantages of a south orientation:
- 🌞 Maximum sunlight in winter: the low sun from December to February directly hits the south facade
- 📈 Higher internal temperature: a gain of 5 to 8°C compared to a poorly oriented greenhouse
- 🌱 Extended season: seedlings can start earlier and harvests extend later
East-west oriented greenhouse: ideal for tunnel greenhouses 🌄
For tunnel greenhouses like those offered by AtmoSerre, the recommended orientation is often the east-west axis: the greenhouse is positioned so that its length runs from east to west, and its widest surface faces south.
In concrete terms, this means that the south side of your greenhouse receives sun all day, from sunrise to sunset. In summer, the sun passes overhead and mainly heats the roof. In winter, it hits the south side very effectively.
This positioning is optimal for:
- ✅ Maximizing sun-exposed surface area
- ✅ Reducing internal shaded areas
- ✅ Distributing heat evenly throughout the length of the greenhouse
Should north be absolutely avoided? ❄️
No north orientation for the main facade is an almost universal rule. In France, the sun never passes north (except for a few hours in late summer evenings). A greenhouse with its main face facing north will be cold, dark, and unproductive.
If your garden gives you no choice, an east or west orientation is better, as it still allows you to capture the sun for a large part of the day.
Analyzing shadows in your garden 🌳
This is the step almost everyone forgets, yet it's one of the most important. A greenhouse can be perfectly south-oriented and still receive too little sun if it's in the shadow of a tree, a wall, or a building.
Cast shadows are tricky for two reasons: they vary with the season, and they are not always well anticipated during the initial scouting.
How to map shadows in your garden 🗺️
Here's the simple method we recommend before any greenhouse installation:
- 📅 Observe your garden at different times of the day: in the morning (9 AM), midday (1 PM), and late afternoon (5 PM)
- 🗓️ Repeat the observation in different seasons: a sunny area in July might be in complete shade in December
- 📸 Take photos to compare shadow positions according to hours and seasons
- 📐 Calculate the height of cast shadows: a 6-meter tree can cast a shadow of over 15 meters in winter when the sun is low
Main obstacles to watch out for ⚠️
- 🌳 Trees: pay particular attention to deciduous trees, which lose their leaves in winter... but conifers cast shade all year round
- 🏠 Buildings and walls: a 2-meter wall on the south side can block the sun in winter for several meters
- 🌿 Hedges: often underestimated, they can create significant shade
- ⬛ Neighbors: a neighbor's house or fence can cast shade on your garden depending on the time of day
The 3-meter minimum rule 📏
In practice, we recommend leaving a minimum clearance of 3 meters between your greenhouse and any obstacle likely to create shade. For large trees or significant buildings, prefer 5 to 6 meters of distance on the south side.
Not always simple in a small garden, but it's the price to pay for a truly effective greenhouse. 💡
The terrain: slope, drainage, and soil type 🌍
Orientation and shadows are the first part of the equation. The second is the terrain itself. A greenhouse installed on poor terrain, even perfectly oriented, can pose significant problems.
Flat or slightly sloped ground? 📐
The ideal is perfectly flat ground. It's simpler for installation, for structural stability, and for water management inside.
A slight slope (1 to 2%) towards the south can even be an advantage: it promotes the flow of rainwater away from the greenhouse and slightly improves sun exposure.
However, a pronounced slope poses several problems:
- ⚠️ Installation difficulty: the structure must be level, which requires earthworks
- 💧 Risk of water accumulation inside if the slope is poorly oriented
- 🌪️ Instability: a greenhouse on sloped ground is more exposed to wind
If your terrain is sloped, it is imperative to level the area before installing the greenhouse. This work, done well, will save you years of complications.
Drainage: an often overlooked criterion 💧
Soil that doesn't drain well is a serious problem for a greenhouse. Stagnant water at the base of plants is the primary cause of root rot, and in a greenhouse where you water regularly, poor drainage can quickly become catastrophic.
How to test your soil's drainage:
- 🕳️ Dig a hole 30 cm deep and 30 cm wide
- 💧 Fill it with water to the top
- ⏱️ Time how long it takes for the water to disappear completely
If the water takes less than 4 hours to infiltrate, your drainage is good. Between 4 and 8 hours, it's borderline. More than 8 hours, your soil is too clayey, and you'll need to improve drainage before installing your greenhouse.
Solutions to improve drainage:
- Add coarse sand or gravel to the bottom of the greenhouse
- Create a peripheral French drain
- Elevate the greenhouse floor with a draining substrate
What soil type for installing a polycarbonate greenhouse? 🌱
For the foundation and anchoring of your greenhouse, the soil type also matters. Soil that is too loose (purely sandy) will not hold anchors well. Soil that is too hard (compact clay or rock) can make concreting anchors difficult.
The ideal soil for greenhouse installation is firm, slightly draining soil, which allows for solid anchoring of stakes or foundation plates.
For AtmoSerre greenhouses, our installation guides specify different anchoring methods depending on your terrain type. Our team is also available to advise you if you have any doubts about your specific situation. 🛠️
Wind exposure: a factor not to be underestimated 🌬️
We talk a lot about the sun, but wind is just as important when choosing your greenhouse location. Strong and constant wind can create three types of problems: thermal, structural, and cultural.
Thermal impact of wind 🌡️
A greenhouse exposed to wind loses heat much faster. This is called the wind chill effect: even with good 6mm polycarbonate, a cold and steady wind cools the structure and lowers the internal temperature.
In winter, this effect can cause a 3 to 5°C temperature drop inside the greenhouse compared to a wind-protected one. This is significant when trying to maintain a minimum temperature for crops.
Identifying dominant winds in your garden 🧭
In France, dominant winds mainly come from the south-west (Atlantic winds), but this varies by region:
- 🌊 Brittany, Normandy, Atlantic coast: westerly to south-westerly winds, often strong
- 🏔️ Rhône Valley, Provence: Mistral (north-north-west), violent and cold wind
- 🌄 Alsace: easterly wind, Foehn in altitude
- 🌤️ Paris and the Paris region: variable winds, often from the west
Observe your garden over a few weeks. Where does the wind most often come from? Which direction seems most exposed to you? This information is valuable for choosing the location of your greenhouse.
How to protect your greenhouse from the wind? 🛡️
Two main options:
Option 1: Use an existing obstacle as a natural windbreak
A wall, a hedge, or a row of trees on the north or northwest side can act as an excellent natural windbreak. Be careful, however: this obstacle must not create shade on the greenhouse. It must be on the north or northeast side, never on the south side.
Option 2: Plant a windbreak hedge
If your garden is very exposed, planting a windbreak hedge a few meters from the greenhouse is a lasting solution. Suitable species: thuja, hornbeam, laurel, photinia.
Recommended distance: 2 to 3 times the height of the greenhouse to avoid casting shade.
Our AtmoSerre greenhouses are designed to withstand winds up to 180 km/h, giving you true peace of mind even in windy regions. But reducing wind exposure always improves the thermal comfort of crops. 💪
To learn more about the resistance of structures in windy conditions, our article garden greenhouse in the face of wind: how to choose the right structure will give you a complete overview of the subject.
Special cases: urban garden, small space, shaded land 🏙️
Not everyone is lucky enough to have a large, sunny garden in the open countryside. Here's how to adapt the placement of your greenhouse in more complex situations.
Urban or semi-urban garden 🏙️
Urban gardens are often surrounded by buildings that create significant shadows and wind tunnel effects. In this context, selecting the location requires even more care.
Our tips for urban gardens:
- 🔍 Accurately map shadows throughout the year before deciding
- 📐 Choose the sunniest spot, even if it's not ideal in terms of access
- 🌿 Opt for a smaller greenhouse but better exposed rather than a large greenhouse partially in the shade
- 🏠 Take advantage of south-facing walls: installing the greenhouse against a south wall can create a very effective thermal collector effect
Small garden: how to find the best compromise? 🪴
In a garden of less than 50 m², the ideal location according to all criteria is often impossible. You have to prioritize.
Our order of priority:
- ☀️ Sunshine: this is the number 1 factor, never negotiable
- 🌬️ Wind protection: important but can be compensated with a good structure
- 💧 Drainage: improvable by work
- 📏 Ease of access: secondary compared to the previous factors
Better a greenhouse that is a little less convenient to access but well exposed, than a greenhouse that is easily accessible but in the shade. 🌱
Naturally shaded garden: can you still have a greenhouse? 🌳
If your garden is surrounded by large trees or buildings, the situation is more delicate. Here's what you can do:
- 🌳 Prune or cut down troublesome trees: not always possible or desirable, but sometimes necessary
- 📐 Choose the sunniest spot, even if it's only 5 to 6 hours a day
- 🌿 Adapt crops: with 5 to 6 hours of direct sun, you can still grow salads, herbs, spinach... Truly sun-loving vegetables (tomatoes, peppers) will be disappointing.
- 💡 Compensate with artificial lighting in addition: horticultural LED strips can compensate for a lack of natural light, but it remains an additional investment.
Comparative table of greenhouse orientations according to seasons 📊
| Orientation | Winter Sunshine | Summer Sunshine | Recommended Crop | Overall Rating |
|---|---|---|---|---|
| ☀️ South facade | ⭐⭐⭐⭐⭐ Excellent | ⭐⭐⭐ Good | All crops, all year round | 🏆 Ideal |
| 🌄 East-west axis (tunnel) | ⭐⭐⭐⭐ Very good | ⭐⭐⭐⭐ Very good | All crops | ✅ Very good |
| 🌅 East facade | ⭐⭐ Average | ⭐⭐⭐ Good | Spring and summer crops | ⚠️ Acceptable |
| 🌇 West facade | ⭐⭐ Average | ⭐⭐⭐ Good | Mainly summer crops | ⚠️ Acceptable |
| ❄️ North facade | ⭐ Very low | ⭐ Very low | Shade crops only | ❌ To be avoided |
Access and ergonomics: practical but not secondary criteria 🚶
We've talked a lot about sun and wind. But the location of your greenhouse must also be practical for daily use. Because a greenhouse that is not used due to inconvenient access is a wasted greenhouse.
Access to water 💧
Your greenhouse requires regular watering. Ideally, a water point should be within 10 meters of your greenhouse to avoid dragging an endless hose every time you water.
If your best location is far from water, consider providing a hose extension or a rainwater harvesting system directly next to the greenhouse.
Access to electricity 🔌
Not always essential, but really practical if you plan to:
- 💡 Horticultural lighting to extend the photoperiod in winter
- 🌡️ Supplemental heating for cold nights
- 🌀 A fan to improve air circulation in summer
If your greenhouse is close to the house, an electrical extension is simple. If it's at the back of the garden, you may need to plan a dedicated installation.
Ease of daily access 🚶
It sounds silly, but it matters. If your greenhouse is difficult to access (muddy path, obstacles, distance), you will go there less often. And a greenhouse that is less monitored is a greenhouse where problems accumulate.
Provide a stable and practicable path between your house and your greenhouse, especially on rainy days when you will still need to go through to water or monitor your crops.
Proximity to the outdoor vegetable garden: a true synergy 🌿
If you have an outdoor vegetable garden, the ideal is to install your greenhouse in close proximity. Why? Because the two spaces complement each other perfectly.
In the greenhouse, you do your early seedlings and your winter crops. In the outdoor vegetable garden, you transplant young plants when the risk of frost has passed. This back-and-forth between greenhouse and vegetable garden is much smoother if the two are close.
In addition, proximity allows you to:
- 🌱 Reuse soil and compost between the two spaces
- 🚿 Share the watering point
- 🔍 Monitor both spaces during a single visit to the garden
Which polycarbonate greenhouse to choose for your location? 🏡
Once you have found the ideal location, you still need to choose the right greenhouse. And here, several criteria come into play.
Size: adapt the greenhouse to your available space 📐
The right location often dictates the maximum size of your greenhouse. Don't try to fit a greenhouse that's too big into too constrained a space. Do you have 6 m² available and well exposed? That's perfect for starting with a compact greenhouse. 12 to 18 m² of well-oriented land? You can aim for a more ambitious greenhouse.
Polycarbonate thickness: 4 or 6 mm depending on your exposure ☀️
If your greenhouse is well exposed and you live in a region with a mild climate, 4 mm polycarbonate may be sufficient for spring-summer-autumn use.
If you want to grow all year round, if your region is cold, or if your location is slightly less well exposed than ideal, 6 mm is clearly the best choice. The additional insulation compensates for some of the losses related to less optimal sunlight.
Our recommendation for a well-exposed location 🌟
L'Intemporelle is our tunnel model that adapts perfectly to most French gardens. Its arched shape minimizes wind resistance, its tunnel structure allows for optimal east-west orientation, and its integrated ventilation windows facilitate thermal management in summer. Available from 6 to 36 m², it adapts to your available space.
Also browse our entire range of garden greenhouses to find the model that best suits your garden, your budget, and your growing ambitions.
The most frequent location errors 🚫
To conclude this section, here are the classic errors we most often observe. Knowing them means avoiding them.
❌ Error n°1: Installing the greenhouse "where there's still room"
Location is not a matter of convenience, it's a matter of exposure. Even if it means reorganizing the garden, sun exposure always takes precedence.
❌ Error n°2: Not checking winter shadows
Observing the garden in summer and concluding that everything is well exposed. In winter, with a much lower sun, shadows can be two to three times longer.
❌ Error n°3: Installing the greenhouse too close to a tree
Roots can lift the soil beneath the greenhouse. Branches can fall onto the structure. And in autumn, dead leaves accumulate on the polycarbonate and reduce light penetration.
❌ Mistake #4: Neglecting drainage
Poorly drained soil under a greenhouse creates problems with humidity, root rot, and can even weaken the structure's foundations in the long term.
❌ Mistake #5: Forgetting daily access
Putting the greenhouse at the back of the garden, far from everything, in a hard-to-reach corner. It gets used less, monitored less, and problems silently accumulate.
❓ FAQ — Where to install a greenhouse in your garden?
What is the best orientation for a garden greenhouse in France?
South orientation or the east-west axis are the best options in France. A south-facing facade maximizes sunlight in winter, when the sun is low. For a tunnel greenhouse, positioning the length on an east-west axis exposes the largest side to the sun all day. Both orientations allow for productive cultivation all year round.
Can a polycarbonate greenhouse be installed in the shade?
It's possible, but not recommended for demanding vegetables. With less than 4 hours of direct sun per day, tomatoes, peppers, and cucumbers will be disappointing. However, lettuces, spinach, lamb's lettuce, and aromatic herbs tolerate partial shade better. If this is your only option, adapt your crops accordingly and choose 6mm polycarbonate to optimize heat.
How far from a tree can a greenhouse be installed?
Minimum 3 to 5 meters on the south and east sides, to avoid casting shadows. On the north side, you can get closer, provided that the branches do not overhang the greenhouse. Also, be careful with roots: some trees (poplar, willow, ash) have very invasive roots that can destabilize the soil beneath the structure.
How do I know if my land is well-drained for a greenhouse?
Do the hole test: dig 30 cm deep, fill with water, and time it. If the water disappears in less than 4 hours, the drainage is good. Beyond that, it will need improvement. Poorly drained soil promotes root rot and diseases. Adding gravel or creating a peripheral drain are the most effective solutions.
Is a polycarbonate greenhouse near a south wall a good idea?
Yes, it's often excellent! A south-facing wall accumulates heat during the day and releases it at night, creating a warmer micro-environment. This is known as a "thermal wall." However, be sure to check that the greenhouse receives good direct sunlight and that the wall does not cast a shadow on part of the greenhouse at certain times.
Does the location of the greenhouse influence the growing season?
Absolutely, and significantly. A well-oriented greenhouse facing south can allow you to start seedlings 4 to 6 weeks earlier than a poorly placed greenhouse, and extend harvests by the same amount at the end of the season. Over an entire year, this is a very tangible difference in yield. To go even further, our article what is the best garden greenhouse for a temperate climate in France will help you adapt your choice to your specific region.
🌱 Conclusion: take the time to choose wisely, your greenhouse will reward you
Installing a greenhouse in your garden for maximum sun is a project that requires real upfront consideration. Not hours of work, but a true observation of your garden, at different times of day and year.
Key points to remember:
- ☀️ Orient the main facade south or position your tunnel greenhouse on the east-west axis
- 🌳 Map out cast shadows in winter before deciding
- 💧 Check drainage and level the ground if necessary
- 🌬️ Identify prevailing winds and position a natural windbreak if possible
- 🚶 Think about daily access: water, electricity, passable path
A well-placed greenhouse is one that reaches its full potential for years. It means a prolonged season, more abundant crops, and a truly more enjoyable gardening experience.
At AtmoSerre, we are here to support you in this project, from choosing the location to the first harvest. Discover all our polycarbonate greenhouses on AtmoSerre.com and find the model that will perfectly suit your garden. 🌿🏡