How to control humidity in the grow tent is one of the most important problems faced by indoor gardeners. In this article, we will address how to control humidity in your grow tent and also provide you with measures that will help protect your plant from moisture and drying out.
If you decide to grow plants indoors, there are many factors you should take into consideration. This is especially true when you decide to use a grow box. Grow tents give you the opportunity to take care of different varieties of plants throughout the year without thinking about the seasons. In addition, you can grow any plant regardless of the climatic zone or weather conditions. Grow boxes help you have a controlled environment that even allows you to use hydroponics instead of conventional soil. One of the biggest advantages of grow tents is that they provide a more efficient environment for plants to absorb nutrients. Grow rooms also keep all potentially harmful elements from mother nature at bay such as molds, pests, fungi, insect larvae or eggs that could harm your plants. You will realize that most indoor gardeners focus on factors such as seed or seedling quality, growth PH, fertilizers, and cleanliness of the grow system, but that they often overlook the humidity in the grow tent. Humidity or the amount of water vapor in the air is an essential factor to keep in mind to ensure you have healthy plants. This article will walk you through the role of humidity in plant growth and all the steps you should take in mind to increase the humidity in your hydroponic grow tent, in case the levels drop too low. Since too high humidity is dangerous for your plants, you will also learn how to reduce the humidity in your grow box.
Why humidity is important
At all stages of growth, your plants will constantly need to provide themselves with water and the amount of water they need is not only drawn through the root system but floats in the air with the humidity in your grow room. When humidity is high, plants use their leaves to absorb moisture from the air which causes them to drink less water from their roots. Conversely, when the humidity is low, they will draw more water through their roots.
Since humidity changes the amount of water your plants absorb and the water you give your plants contains nutrients, humidity control gives you more control over nutrient intake.
But controlling humidity isn't just about prevention ... having the right humidity favors strong, healthy, leafy plants with vigorous growth. In fact, growing with DWC (Deep Water Culture) / Bubbleponics during the vegetative phase with the correct humidity can actually turn into a struggle to tame the uncontrolled growth of plants! Also, after your plants have started producing buds in the flowering phase and are nearing harvest, you can adjust the humidity of your grow area to make your plants produce more resin (trichomes / glitters that contain THC and other cannabinoids) preventing plants from being attacked by mold. Too high humidity can sometimes in fact cause mold or sprout rot - a grower's worst nightmare for those greasy, dense main buds.
How to control temperature and humidity in a grow box
Air conditioning systems
When growing marijuana outdoors in a suitable climate, you don't have to worry as much about how the weather affects your crop. For indoor growers, on the other hand, lighting is essential. While you're tempted to blow up your room with powerful lights, you also need to be careful, as too much lighting raises the temperature in the grow box. A common mistake is buying an air conditioning system that is too big or too small for the grow room. As a result, frequent fluctuations cause temperature chaos. When it comes to AC (air conditioning) and sudden changes in temperature, the short cycles of power on and the dead band are the two key factors. In case you didn't know, the deadband is a range of 3-5 degrees around the temperature you set the room thermostat to. When the temperature reaches the upper end of the dead band, the air conditioning unit will turn on to keep the room at the right temperature. When the temperature reaches the lower end of the dead band, the AC turns off to prevent the room from getting too cold. If your AC system is too large it will run in "short cycles" which means it will consume a ton of energy and create an unreliable growing environment where humidity and temperatures rapidly rise and fall several times a day. If the AC unit is too small, the grow room temperature will rise to an uncomfortable level for the plants. Most importantly, marijuana plants thrive in a consistent climate, so short cycles can be disastrous for their growth. Short cycles cause unwanted temperature spikes. Since humidity levels are inverse to temperature, an increase in temperature leads to a reduction in relative humidity and a drop in temperature leads to a reduction in relative humidity. The resulting unstable growing environment becomes an ideal breeding ground for mold and mildew. Therefore, the challenge for growers is to find an air conditioning unit of the right size for their grow room. In an ideal world, on a graph, your grow room temperature should look like a long, shallow wave.
Extractors
The most practical method of controlling humidity is often through ventilation. Humidity can be easily reduced by increasing or decreasing the amount of air exchanged throughout the room. This is usually done by adding an extractor. To increase the effectiveness of the exhaust fan, an intake hole can be added or enlarged, causing more air to be moved through the room. It may be necessary to build a light deflector around the intake hole to prevent light leaks and still allow abundant airflow. For more reliable automation and greater efficiency, a hygrometer controller can be used to power the fan instead of a timer or thermostat. Since plants technically require fresh CO2 rather than constant fresh air, many rooms configured with CO2 injection systems have little or no ventilation. Rooms configured this way use dehumidifiers to control humidity and extra air conditioning to control temperature. The closed area and the lack of ventilation causes an increase in humidity. Furthermore, the increased metabolic rates that plants get from the added CO2 lead to greater transpiration and a further increase in humidity. In this situation, a humidifier would not be needed but rather a dehumidifier.
Seal and insulate your room
One of the key principles for successful indoor marijuana growth is ensuring your grow room is properly sealed and insulated. In the modern era, commercial builders use foam insulation and other materials to create a thick barrier between the marijuana grow room and the outside environment. If you live in an area where outdoor humidity is relatively low, you may think this tip is not for you. However, it remains a necessity regardless of whether you live in Spain or the Netherlands because it prevents external factors like humidity, ventilation and sunlight from negatively impacting your weed. These three factors, along with a few others, have a significant impact on temperature. As mentioned above, temperature and humidity levels are closely related. If you insulate your grow room properly, you don't have to worry about external factors that can damage your crop.
Transpiration of plants and its effect on the cultivation environment
Plant density also affects humidity levels. The air in the room is displaced by increasing the number of plants, which also act as windbreaks and prevent other areas of the room from receiving fresh air and CO2.In addition to the displacement of air, other plants cause an increase in humidity due to the greater perspiration. Without adequate ventilation or dehumidification, the water vapor transpired by plants has nowhere to go. For this reason, as the density of plants in the garden increases, the need for ventilation also increases. In this scenario, if the extractors cannot keep up with the high humidity created by the increased perspiration, a dehumidifier may also be needed. If the high humidity level is not corrected, transpiration is hampered and the overall metabolic rate of the plants decreases. To prevent slow metabolism and slowed plant growth, keep in mind the impact of plant density and transpiration, and be productive by monitoring humidity levels with a meter before these problems arise.
The importance of ventilation
Although humid air holds more water, it is actually lighter than the air around it. Therefore, go up to the ceiling of your grow room. Meanwhile, CO2, which is a key component for plant growth, stays close to the floor. Consequently, your grow room must have excellent air circulation. Many growers find that oscillating wall fans are sufficient. In fact, they help, but they only reduce the temperature and do not always and completely manage to provide air circulation. If you want a successful harvest, you need good airflow throughout the room. It must come from the walls and from the top and bottom of the room. If you can afford it and have the necessary space, we advise you to purchase floor standing fans: they guarantee greater air circulation and balanced humidity levels, equal CO2 distribution and a stable growth room temperature.
Humidity during germination and propagation
When germinating seeds or rooting cuttings, it is extremely important to maintain much higher than normal humidity levels (80-90%) to promote initial root growth. If the humidity is too low, the water vapor pressure deficit will encourage too rapid transpiration to allow energy for root development. An ultrasonic humidifier or nebulizer can be added to ensure that the relative humidity remains at an adequate level. Another useful tool for keeping humidity levels high enough for seedlings or cuttings is a small greenhouse with a lid, which can be used to grow young plants and to create a microclimate where humidity levels remain above ambient levels. Another thing to consider when germinating seeds or rooting clones is that although the relative humidity needs to be kept much higher than ambient levels, the moisture level at the roots should normally be treated by providing them with plenty of oxygen between the plants. watering.
Here are some guidelines on the ideal humidity and temperature levels for the various stages of your plants:
SEEDS AND CLONES
* Humidity 65-70%
* Temperature during daylight hours: 20-25 ° C
* Temperature in the hours of darkness: 15-20 ° C
VEGETATIVE PHASE
* Humidity 40-65%
* Temperature during daylight hours: 22-28 ° C
* Temperature in the hours of darkness: 17-23 ° C
FLOWERING PHASE
* Humidity 40-50%
* Temperature during daylight hours: 20-26 ° C
* Temperature in the hours of darkness: 15-21 ° C
CLEANING PHASE
* Humidity 30-40%
* Temperature during daylight hours: 18-24 ° C
* Temperature in the hours of darkness: 8-14 ° C
Use a properly sized dehumidifier
One might imagine that buying a high-quality dehumidifier is at the top of a grower's list of new equipment. However, many people tend to save on purchases, buying cheap and invariably end up paying twice. In reality, residential dehumidifiers are a waste of money because they are not designed to manage the humidity level in a marijuana grow room. Hence, they use a lot of energy and are extremely inefficient. For many growers, the cost of a commercial dehumidifier seems too high, but ultimately they are forced to pay twice and buy a more suitable one due to humidity problems in their grow rooms. Keep in mind that plants transpire all but 3% of the water they absorb. Therefore, it is necessary to size a dehumidifier correctly to extract the right amount of moisture from the air. If you have a large grow space, you will probably need several dehumidifiers. Make sure you design your system in such a way that if one unit fails, the others continue to function smoothly. While it probably seems expensive at first, you will save a lot of money on electricity compared to dehumidifiers designed for housing units. We hope this guide has proved useful. It is important to remember that plants with Indica genetics tend to have dense buds and are more sensitive to bud rot in humid conditions than their Sativa counterparts. We recommend that you check your plants regularly and you should also invest in a high quality thermometer and hygrometer. All-in-one thermohygrometers are available that can measure both temperature and humidity.
In summary, to keep the humidity in your grow room under control, you need to:
* Make sure it is properly sealed and insulated.
* Monitor lighting and maintain a specific temperature range.
* Increase the supply of fresh air.
* Make sure there are no stagnant pools of water.
* Use a dehumidifier of adequate size.
* Use a thermo-hygrometer.
Conclusion
Growers need to pay close attention to temperature and humidity levels, as well as how they affect each other, to fully understand the impact of environmental factors on plants. If the temperature and humidity levels are high, plants are not encouraged to transpire and growth slows down. To encourage transpiration and maximize growth potential, it is necessary to achieve a higher Vapor pressure deficit (VPD) by reducing relative humidity or increasing temperatures. Since rising temperature levels can further increase humidity levels and plants may get stressed, humidity control remains the preferred choice. If the temperature and humidity levels are too low, the plants are not encouraged to transpire and growth slows down. To encourage transpiration and maximize growth potential, a higher VPD must be achieved by raising temperatures to a safe level while maintaining lower humidity levels. Understanding VPD will not only allow growers to make necessary corrections to the environment, but also to anticipate environmental problems before their effect has had a negative impact on their crop. For maximum yield and quality, humidity levels should be controlled with the use of a hygrometer controller, extractor, dehumidifier or humidifier and fans. There are also control units capable of automating processes to always keep levels under control. Once you understand how temperature affects relative humidity and their combined effect on transpiration rates, your plants will thank you for learning the roles these environmental factors play in the garden and how and when to control them.