If you’re wondering what helps greenhouse plants stay small, two factors generally affect their growth- temperature and humidity. In this article, we will find out how greenhouse plants keep their size.
Without a doubt, greenhouses are ideal for growing plants; you have control of all the elements essential for your plants, providing you with a better yield. The control is proper, especially for the UK areas with a cold environment or where plants can’t strive – buying a polytunnel is the best choice.
Now, it’s time for you to learn more, so just read on!
Factors That Keep Greenhouse Plants Small
This section will discuss temperature and humidity; they’re the two main factors that keep polytunnel plants small. Later on, you will find out some of the things that can help control these factors. Let’s delve further so you will understand better.
Temperature and humidity to maintain plant size
Air’s temperature has an impact on the plant’s ability to holding moisture. Warm air holds more water vapour, which has higher relative humidity. Therefore, you can say that the temperature is relevant in controlling humidity.
Relative humidity, on the other hand, determines the amount of water vapour present in the air. It expressed in percentage, and it shows how much needed for saturation. This factor affects your plant’s biological process, especially transpiration.
Transpiration is when plants sips in water from their roots, transports water to their tissue and releases it back to the atmosphere through their leaves. It is essential for the growth and development of the plant. Also, it is responsible for releasing the water into the air, which helps the plant cool down.
You may say that plants sweat too. If we sweat a lot in a very humid place, you’d feel uncomfortable, won’t you? Just as relative humidity stops our sweat from evaporating, high humidity disturbs the transpiration process of your plant. It will be a threat to your plant’s growth.
How to control humidity and temperature
Now that you are familiar with the factors affecting your plant’s growth, you’d also want to consider the external factors outside the polytunnel as they could also affect what’s inside.
The temperature and weather outside your mini polytunnel changes. Therefore you’d want to maintain the condition inside to keep your plant healthy and growing properly.
Since humidity and temperature are what helps polytunnel plants stay small, you need to know how to control them. Here are the ways:
#1 For humid areas in the United Kingdom
If you’re already living in a humid environment, passive and active ventilation are popular. It is perfect for controlling the humidity and temperature in such an environment, as it moves the hot air up and out and cold air in, regulating the temperature.
#2 For dry areas in the UK
However, in drier places in the UK, evaporative cooling would be the best option. Ventilation isn’t enough since the humidity in this area is lower. Evaporative cooling works by adding moisture inside the polytunnel environment; this will eliminate unnecessary heat while letting the moisture in.
The system controlling humidity and temperature
Now, you already know the ways on how to control humidity and temperature inside your greenhouse. We prepared more; you have to use equipment to help polytunnel plants stay small.
Here are some more things to use to control the humidity and temperature of the greenhouse:
#1 Use a fan and pad cooling system
A commonly used technique by the UK plant growers involving a fan and pad system, a large wet wall is installed on one wall, and a series of exhaust fan placed on the opposing wall of the greenhouse. The pad is continuously released water vapour with the help of a water supply.
The air will then pass through the pad. The cold and humid air will then move towards the polytunnel with the help of the exhaust fan and released into the outside atmosphere.
It is easy to use and cheap. However, the pad is somewhat prone to bacterial growth and mineral deposit. The temperature gradients of both the pad-wall side and fan-wall side may be uneven.
#2 Use a high-pressure fog system
The system uses nozzles distributed evenly inside the greenhouse. Series of nozzles would then inject water droplets in the form of an artificial fog in your greenhouse.
A high-pressure fog system is a better alternative for a pad and fan system as it gives even coverage and consistent atmospheric condition for your small greenhouse. But of course, it has its flaws as well.
You need to control the size of your water droplet; smaller droplets are not enough to give the moisture your plant needs, and bigger droplets might destroy your plants.
Both systems work just fine for any size of greenhouse. However, if you’re looking for a cheaper alternative, then shade curtains will help you with that. Shade curtains will serve as a thermal shield and will keep heat if needed.
It will help in reducing heat when the temperature outside is hot. In contrast, when you place sheer curtains at night, the temperature inside the polytunnel would be regulated if ever the heat outside drops.
But use it properly as it might hinder your plant’s photosynthesis and transpiration process.
If you think growing plants will only be watering them daily, then think again. Significantly if you’re growing plants inside a greenhouse in the UK, you have to consider factors inside and outside to maintain a suitable condition for your plants to grow.
Just a reminder, consider your environment before you construct a polytunnel to know what appropriate products to use. Again, water, sunlight, humidity, and temperature are some of the things you need to make sure to keep your plants healthy.
Once again, the relative humidity is what helps the greenhouse plants stay small. So, make sure to control the condition inside your polytunnel if you want it to be more significant. We hope that we helped you answer your questions. God bless, and thank you for reading!