The question, “What too hot a polytunnel temperature is?” Usually is answered depending on what type of plant is inside. The ideal temperature inside of your polytunnel in the UK changes for every plant, as various plants require a different amount of temperature to strive.
Nevertheless, if you want to learn more about what too hot a polytunnel temperature is, just read on!
Temperature Ideal For Your Greenhouse
Have you ever wondered if greenhouses get too hot? Well, the answer to that is yes. So, what too hot a polytunnel temperature is? The maximum temperature that plants can cope with is 80 degrees Fahrenheit, and if it goes higher than that, your plants might wither.
However, there are types of plants that can withstand a whopping 90 degrees Fahrenheit! But of course, you don’t want to go too far from that as greenhouses can quickly warm themselves.
Regardless, here is a list of heat-tolerant and heat-sensitive plants for your awareness in the UK:
Heat-tolerant plants
The following plants can enjoy the summer heat together with you, as they can strive even the temperature is 90 degrees Fahrenheit.
- Eggplant
- Okra
- Tomatoes
- Sweet potatoes
- Arugula
- Cucumbers
- Cabbage
- Watermelon
- Beans
- Chilli peppers
Despite the plants having higher heat tolerance, it is unnecessary to let heat levels reach 90 degrees as it can slow down the photosynthesis of your crops.
However, they can still sprout despite the heat, making them the perfect starter plants for those new to polytunnel gardening in the UK, who are still afraid to make their polytunnel too hot.
Heat-sensitive plants
The plants we will mention needs extra care; they can only handle temperature at around 75-78 degrees Fahrenheit.
- Beets
- Broccoli
- Carrots
- Collards
- Cauliflower
- Peas
- Brussels sprouts
- Kale
- Onions
- Lettuce
The following plants are sensitive when the temperature reaches 85 degrees Fahrenheit. Therefore, you’d want to lower down the temperature inside for these plants to survive.
Especially in summer, if you want the kale to add to your diet, ensure that the temperature wouldn’t go up to 85 degrees Fahrenheit.
What Causes Greenhouses To Overheat?
Aside from knowing what too hot a polytunnel temperature is, you should also understand that there are instances where certain factors trigger your grow room to create or store more heat. Here are some reasons:
Location of your greenhouse
It might be where you place your greenhouse. You might say that “Well, that is where sunlight usually hits” I mean, it’s good that your plants get plenty of sunlight, but remember that too much of it can kill them.
Therefore, we suggest you place a thermometer inside your polytunnel to monitor the temperature changes. You also don’t want the weather to keep changing as it disturbs your plants’ process by keeping them adjusting.
Be constant, and always remember to provide the right amount of heat, sunlight, and water for your greens to be healthy.
External environment
Adding to this, the temperature outside your polytunnel can either increase or take off the heat inside.
The polytunnel traps heat, which helps the ground inside warm-up, beneficial for your plant’s growth. In contrast, if the weather outside is too hot, you might also turn off your heater and water your plants to regulate the heat.
Also, make sure that your polytunnel has adequate ventilation to welcome fresh air inside, as too much humidity may cause diseases to your plants.
Ways To Cool Your Greenhouse
Now that you’re full of information regarding greenhouses’ maximum temperature might as well add up how to cool it down.
There are various ways to keep your polytunnel cool, especially in summer. You don’t need to worry about your budget as some of them don’t require you to spend any cent! Read on to learn more!
Ventilation system
Sounds expensive? Well, it’s only opening your polytunnel doors or vents to let air in, simple as that!
Ventilation is the most straightforward way to cool down the grow room; it allows airflow to let heat out by allowing the air outside to go in.
Using fans
Just like us, we use fans to cool ourselves during summer. Same as a ventilation system, it allows airflow to cool down your greenhouse.
If opening your polytunnel door won’t work, then maybe it’s time for you to open your wallet and start investing in a fan.
Shade
As simple as it may sound, placing your polytunnel underneath a shade will help it cool down. Every time you hear the word “shade,” you’d automatically think of trees. Therefore, having trees with large leaves and tall canopies will help you a lot!
However, if you don’t have trees in your yard, use shade cloth and nettings as an alternative. A suitable material would be aluminium, for that doesn’t heat the inside of your greenhouse.
Water
Watering your plants regularly just won’t cut it. Especially in summer, just like how people get dehydrated because of the lack of water or drink small ounces of water, plants will need more water to help them cope with the hot weather.
Plants sweat too! Through transpiration, they cool themselves by losing moisture. Therefore, they need to stay hydrated also!
Conclusion
Now, knowing what too hot a polytunnel temperature is, we hope that you’d provide your plants with their basic needs to strive and yield bountifully in the United Kingdom. Just be patient, and stay determined.
We hope you’d apply your learnings from this article. Thank you for reading, and we are positive that you’d read from us again!