Cannabis ruderalis plants that live in the wild flourish in areas where there are short summers and very little rainfall. These plants thrive, are happy and grow strong in these perfect conditions. Generally, cannabis plants hate high humidity and therefore if you are trying to grow autoflowering plants indoors you must maintain optimum humidity so your plants can grow and bloom. And first things first, here are a few basic facts about humidity and how to measure humidity inside your grow room.
Understanding Humidity and Measuring Humidity
Humidity is the amount of water vapor in the air. Absolute humidity is the maximum amount of water vapor that the air can hold at a specific temperature. Relative humidity is measured in percentage from the absolute humidity value. The best way to measure humidity is by using a hygrometer. You will find traditional hygrometers while there are also digital ones that are easier to read. Still there are better digital models that show a high and low humidity feature so you will know how much the humidity and temperature changes at night or during the daytime.
The optimal humidity in growing autoflowering plants
The optimal humidity ratio for an autoflowering cannabis plants changes due to many environmental factors. Initially, the optimal humidity of autoflowering cannabis plants during the preflowering stage is between 40% to 70%. Humidity must not be over 90% or else your plants will greatly suffer. Water found in its leaves and stems will never be able to evaporate at this high humidity and this can completely affect the plants growth and its ability to reach its full potential.
Because preflowering is a very crucial stage for autoflowering plants, you need to maintain the ideal humidity of 55% or somewhere between 20% to 40%. You must adjust and maintain the ideal humidity as soon as cannabis plants start to show flowers because high humidity can increase the plant’s risk of suffering from infections and mold growth.
High humidity can cause mold to grow since mold spores may use dense buds as a place to proliferate and spread. If you are not careful your plant will be completely affect by mold in just a few days if you are not careful about humidity. Mold is also undetectable during the preflowering and flowering stages, it stays inside the bud and then spreads to the entire body of the plant. It may be too late to save your plant if you are not careful.
How to manage humidity in your grow room
At the preflowering stage, your grow room must have 40% to 70% humidity but as soon as the buds open, the humidity must be decreased and maintained below 50%. There are a number of ways to improve the humidity indoors and here are the best ones for cannabis growers:
- Decrease humidity by increasing room temperature
So technically you don’t just need a hygrometer in your grow room but you also need an indoor thermometer as well. Increase room heat by raising the heater temperature. And while this is an easy way indeed, it could be may not work for all strains and for all growers because a large number of autoflowering strains hate temperatures above 32C or 89F. You must keep in mind the ideal growing temperatures of a particular strain to be able to establish an ideal growing temperature range for your plants.
- Use rock salt
One ingenious way to reduce humidity in grow room is to use a bowl of rock-salt. Salt is known as a natural material that can draw out moisture from anything. This is why rock salt is used in preserving fresh food like meats, fish and cold cuts. Simply place a handful of rock salt in a large bowl. Place it in the corner of your grow room and just let it do its magic. Soon you will find that your room will have lower humidity as days go by. You can increase the humidity by removing the bowl of salt from your room.
- Use an electronic dehumidifier
If there is a humidifier that can improve humidity inside a room, there is also a dehumidifier which can reduce it. Electronic humidity will quickly, effectively and precisely reduce humidity levels inside your grow room by drawing water from the air. There are many sizes and shapes of dehumidifiers. For a small grow room, you can use a small portable dehumidifier. You can check out different models online and see which one works for your needs and room size.
Take note that you need to be careful in increasing humidity inside your grow room since too much water can cause buds to develop molds. Constantly take note of the optimal immunity inside your grow room and use these methods only if you really need to increase humidity.
- Use hand misters
A simple hand mister will be able to increase water vapor inside your grow room. Just be careful in using a hand mister during the flowering stage since water can easily get on the dense buds. Just use these during the initial growth stages of your plant.
- Use a bowl of water
Placing a large bowl of water inside your grow room will also easily increase humidity. Place it near the furnace or near a heat source. This is a better solution in increasing humidity since water won’t accumulate on your precious cannabis buds.
- Use an electronic humidifier
A humidifier will be able to correctly and effectively add water vapor in the air to correct humidity in your grow room. Using a humidifier is an easier way to correct optimal humidity indoors but is considered a very drastic measure. Too much humidity can turn a small area like a grow room into a humidity dome. This area will be too rich with moisture and will be severely damaging to your autoflowering plants as well as to a large number of cannabis plants as well. Therefore you should use an electronic humidifier sparingly.