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Should Greenhouses Have Ventilation? The reasons why

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wooden greenhouse with windows open

To have a greenhouse that can foster the growth of your plants to their full potential, one must look into its most significant part, that being ventilation.

A greenhouse absorbs sunlight inside the structure for making a warmer growing environment inside. Proper Ventilation in greenhouse guarantees that your plants get a lot of natural air that they can use for photosynthesis. Additionally, excellent Ventilation prevents pest infestations and will empower significant fertilization inside the Greenhouse.

If you encounter that your plants are not getting enough nourishment, you can choose the correct fans and vents for your Greenhouse.

Greenhouses – a rundown

Greenhouses are structures made from polycarbonate plastic, fiberglass, glass, or polyethylene heated and climate-controlled.

Greenhouses absorb light and retain most of the heat from that, which helps plants through cold weather.

They can come in two different forms; a free-standing and an attached greenhouse. The former is the type of greenhouse that is movable and can be placed anywhere in your property, while the latter utilizes a load-bearing wall as one of the greenhouse walls.

Aspects of a greenhouse

large tunnel with flowers

Having a productive greenhouse depends on several factors. From choosing the right location to picking the right plant species and getting enough sunlight, there is much more to Greenhouses than just capturing the sunlight and a proper location.

Several aspects are essential in a greenhouse are as follows:

  • Temperature
  • Moisture level
  • Airflow (most important)
  • last but not the least, Ventilation

A significant factor why greenhouses need ventilation is that the greenhouse absorbs sunlight inside the structure.

A greenhouse with proper ventilation gives the gardener a growing environment on their plot, where they can create their natural climate and provide them with space and air to create their microclimate.

Greenhouse ventilation is necessary, as this can help the new seedling and give them protection throughout their fragile juvenile phases. It also gives the plants an extended season to grow on.

Ventilation Systems in Greenhouses

small tunnel with door open

Some people think that everything they need to keep running whenever they buy greenhouses, especially the free-standing ones, is there. But that is not the case.

The greenhouse is a structured building that cannot do anything regarding the outside environment, meaning that it has no way of solving that if it gets too warm because of directed rays into the greenhouse.

The same will be for when it is winter outside. The greenhouse can only stand on its own and shelter the plants, but the plants could suffer inside without proper warming or cooling processes.

This is why it is necessary to look into tools and components which will aid the greenhouse to heat or cool itself, and they are known as the ventilation system.

Proper ventilation in a greenhouse and its capabilities

Proper Ventilation helps manage greenhouse temperature, and it also guarantees that your plants are getting enough natural air that they can utilize for photosynthesis.

The temperature of the Greenhouse, humidity level, and ambient CO2 level, all of these are determined by the ventilation system.

Ventilation is needed to prevent overheating from happening inside the greenhouse. The system regulates humidity and temperature inside and allows for better air movement and proper exchange of gasses between plants.

Considerations for getting a ventilation system

commercial polytunnel with fans

I suggest you purchase the ventilation system upon buying your greenhouse and directly installing it into the walls. The exhaust fans needed for larger greenhouses are recommended to be installed on the roof itself as well as the greenhouse’s perimeter base to allow heat to escape.

However, different material-made greenhouses can call for different ventilation formats.

For example, a polycarbonate greenhouse’s ventilation system could be a money saver because you can just cut into the polycarbonate to create holes and aid in ventilation.

Still, having second thoughts as to why greenhouses need ventilation? Read on to the next part to understand the importance and reasoning why ventilation should be an important consideration for these structures.

Reasons why Greenhouses Need Ventilation

Greenhouses, may it be any size and any type, will need some form of ventilation to ensure a proper atmosphere to foster growth in plants. We will be talking about the specific reasons below.

1: Temperature Control can be done by adding ventilation in greenhouses

An adequate and properly controlled temperature is necessary inside the greenhouse.

The main reason for greenhouse ventilation is temperature due to the inside being hot, even in the cold climate.

Plants tend to die with excessive heat inside a greenhouse. Some are so sensitive to this temperature that they either wilt or die.

This is why there is a need for vents inside the greenhouse to keep the plants healthy. It will keep the temperature regulated and will keep the natural heat away.

Utilizing an evaporative cooler related to an exhaust fan is the ideal approach to cool down your Greenhouse in hot atmospheres. You can also consider using an exhaust fan to introduce the flow of fresh air inside the greenhouse.

2: Air Circulation is possible by adding ventilaiton in greenhouses

Air circulation is the big reason why greenhouses need ventilation. The airflow and the air movement can regulate the temperature and humidity within the greenhouse.

Air circulation aids with the oxygen exchanges and helps pollination. 

The wind, too, is essential to develop robust plants. Due to the plant growing and being nourished in this environment, they typically grow more muscular cell walls to protect themselves.

3: Adding ventilation in greenhouses introduces Fresh Air to the plants

Everyone knows that plants need carbon dioxide to photosynthesize. You can bring them in by allowing fresh air into your Greenhouse. All you have to do is get some vents to make the fresh air come inside the structure.

Plants need Carbon Dioxide to grow stronger; that is is why larger greenhouses often opt to have carbon dioxide generators.

Instead of buying those, we can introduce said gas into the greenhouse by letting fresh air in.

The circulation of the carbon dioxide in the fresh air is aided by a fan, which moves the air inside and around the greenhouse. 

4: Pests Control can be done by adding ventilation in greenhouses

Many individuals neglect the fact of how Ventilation affects the pests within greenhouses. 

If the air is not circulating in your Greenhouse, many bugs will feel comfortable coming inside, which in turn damages your plants and makes them sick.

By placing some fans or vent systems, you can save your plants plagued by pests such as whitefly.

You can eliminate these annoying bugs by placing large fans near your plants to ventilate your greenhouse and protect your precious plants.

5: Oxygen Exchange is doable by adding ventilation in greenhouses

If a greenhouse is not well ventilated, the air inside the greenhouse building becomes saturated. With this, the plants will not get enough carbon dioxide that they need to photosynthesize and grow.

Plants also require oxygen to survive. Having a good supply of fresh air and exchanging oxygen through proper ventilation will help develop healthy growth.

6: You can introduce easy pollination by adding ventilation in greenhouses

large tomato and tunnel

Pollination is an essential part of the growth process of plants. As in greenhouses, you don’t have enough natural wind; it’s necessary to get the required air through good fans.

Moving air inside your greenhouse will allow pollination to occur.

By moving the air, the plants will gently shake, and pollination will occur. This process is essential for some plants like tomatoes, which are self-pollinating.

The gentle airflow inside your greenhouse will also encourage your plants to improve their overall health and urge them to create sturdier stems.

7: Relative Humidity can be kept in check by adding ventilation in greenhouses

Many people may not know this, but the disease starts and runs rampant when the relative humidity increases past 80% on many plants.

At 90% relative humidity, there is a risk of fungal problems within the greenhouse; keeping it under 70% relative humidity will keep such issues under control.

You can install humidity fans to ventilate your Greenhouse and prevent this problem from happening.

The balancing act of ventilation and heating, as well as good air circulation, will keep your plants healthy and grow stronger.

8: Reduction of Heat load is possible by adding ventilation in greenhouses

plastic tunnel with vents

With proper Ventilation, we can reduce the heat load in our Greenhouse. One of the primary purposes of Ventilation in a greenhouse is to blow the warm air out.

As excessive sunlight produces heat, it increases the Greenhouse’s temperature making it necessary to ventilate your Greenhouse.

Using a proper ventilation system, you can provide the plant with the ideal temperature for its healthy growth. A sensor can notice the temperature change. Once it reaches its limit, it can send a notice to open the windows or open it electronically if your ventilation system has this mechanism.

9: You can add ventilation in greenhouses and do Cross Ventilation

Cross ventilation is a critical way to help decrease the temperature inside the Greenhouse.

It is known to be the most natural type of ventilation, as it freely allows the fresh air to enter inside your Greenhouse and flows across the Greenhouse.

You can do this by placing the exhaust fans towards the roof of your Greenhouse and the opposite door. Make sure to add extra circulation fans if your Greenhouse does allow you to add exhaust fans.

Conclusion on why greenhouses need ventilation

Hopefully, all this information will help you decide to have a greenhouse in your home and the necessary tools needed to help it ensure optimal growth and care for plants.

While most of this article talks about larger-sized greenhouses, you can also consider getting mini-greenhouses if your home has limited space or other factors. I have written an article on the benefits of getting a mini greenhouse in this article.

They are generally cheaper, and all it takes to ventilate them properly would be a small fan and possibly using a sheer cloth on its top and sides to regulate the temperature within. Hopefully, this is a good entryway for you to dip your toes into using greenhouses.

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