Getting the temperature right for your cannabis plants is an essential part of each stage of the growing process. If the temperature in your MARIJUANA GROW TENT or outdoors is too hot or too cold, your young weed plants will not be able to photosynthesize properly, and this will inevitably affect their growth and development. However, it is not as simple as saying 'this is the correct temperature; the temperature needs of the plants vary according to their stage of development, so you must have some knowledge of their requirements. To help you, we have written this guide which will explain the best temperature and humidity for growing weed for each phase of your young weed plants.

Now, we understand that establishing the ideal temperature for weed plants can be tricky - some say that it is as much instinct as it is science. However, it is certainly possible to work things out for the growing conditions of your plants, and this article will tell you everything you need to know.

What you need to know about temperature and humidity

The first thing you need to understand is the close relationship between temperature and humidity levels. Let's look at science. Humidity refers to the amount of water vapor present in the air. At higher temperatures, molecules move at top speeds; thus the probability of condensation of water vapor due to the collision of molecules is less. This makes the air hold more water vapor at high temperatures. In other words, as the temperature increases, the humidity of air also increases.

Most plants including cannabis plants, need humid air to thrive. This is because the pores through which they breathe lose most of their moisture when the surrounding air is dry, a loss that the plant can't always replace through the water absorbed by its roots. The thinner the leaf - and cannabis plants have quite small, narrow leaves, the higher its need for humidity.

When deciding the correct temperature for your plants, therefore, it is also sensitive to assess the humidity levels as the two go hand-in-hand. To do this, you should invest in a good-quality thermometer and a hygrometer, ideally digital models with the ability to store historical maximum and minimum levels.

When the temperature is 68 ° F (20 ° C), air can absorb 7.2 ml of water maximum. When this occurs, the air has a relative humidity of 100 percent. There will be so much water vapor that the air will be as dense as a cloud and will affect your ability to see anything. Air with a temperature of 32 ° F (0 ° C) is only able to absorb about 5 ml of water. This is the reason why the air is a lot drier in the winter than in the summer.


We need to define what humidity and temperature control actually means when growing cannabis. It makes sense to divide the life of cannabis plants into 4 different stages in which humidity levels, and temperatures, should be adjusted to ensure healthy growth. Don't think that humidity and temperature control is complicated and not worth it! It's generally very easy, and more about keeping parameters within a certain range, and as constant as possible.

The first thing you need to do is to buy a hygrometer and thermometer, preferably a digital one with memory function, also showing maximum and minimum values of the past. Some hygrometers aren't the most accurate, so don't bother having several devices in your grow room to compare values. Now that we're able to closely monitor our conditions, we can get to the essence of humidity and temperature control - the actual humidity levels and temperatures we aim for.

1. Seedling Stage

  • Seedlings and clones like high humidity levels of 65-70%
  • Reason: The root system is not established
  • High humidity levels allow water intake through leaves
  • Temperatures with lights on: 20-25 C ° (lights off: 4-5 C ° lower)

2. Vegetation Period

  • Humidity levels can be lowered by 5% each week (acceptable range: 40-70%)
  • Temperatures can be increased a little bit (no obligation)
  • Reason: Roots absorb more water; evaporation through leaves cools plant (s)
  • Temperatures with lights on: 22-28 C ° (lights off: 4-5 C ° lower)

3. Flowering Period

  • Humidity levels need to be lowered to 40-50% (extremely important)
  • You can get away with 55% (anything over 60% is real bad)
  • It's best to slightly lower temperatures in flowering
  • Temperatures with lights on: 20-26 C ° (avoid high temperatures)

4. Late flowering (1-2 weeks before harvest)

  • The following steps are no necessity, but can improve yield, flavor and appearance
  • Bring down humidity levels as much as you can: 30-40%
  • Lower daytime temperatures, and also increase the temperature difference (day / night)
  • Temperatures with lights on: 18-24 ° C (lights off: minus 5-10 C °)

What Happens If the Air in the Grow Room Becomes Too Dry?

Dry air results in your plants losing more water when breathing than in moist air. This reduces the overall moisture content in your weed. If the environment gets too dry (low humidity), your plants lose more moisture than they can regain through their roots.

If this happens, your plants close the pores in their leaves to minimize water loss. It is an effective tactic, but it means they receive less CO2 from the environment. The result is cell death within your cannabis plants.

It is tempting to think that you can just water your plants more often in dry conditions. However, you will end up over-watering the soil and reduce the amount of air in the growing medium. Your plants will suffocate and become more likely to develop root rot.

If you allow excessively high humidity levels, you increase the risk of diseases such as bud rot. The reason for this is that it allows moisture to build up in the plants' thick foliage.

By setting your grow room to the right humidity level, your plants flourish. They open their pores, breathe CO2, and grow quickly. Leading marijuana growers say beginners should look to achieve the following humidity levels in their grow room. Naturally, this is determined by the length of the marijuana plant's life cycle.

Why we need aa humidify for grow room

A plant's water needs are equal to the amount of water lost by evapotranspiration. Different types of indoor plants have different water requirements.

You can avoid evapotranspiration of your indoor plants by increasing the humidity of your grow tent. Misting the air ensures that your plants preserve moisture.

A high-quality humidifier is a convenient and relatively inexpensive way of misting your grow room. Just set the dial on a specific humidity.

The humidity changes to the desired level as soon as the humidifier is able to mist enough water into the air.

Choosing the BEST HUMIDIFIER FOR GROW ROOM plants or your indoor garden doesn't have to be a difficult proposition. Here is the top model to consider.

微 信 图片 _20200910164247.png


Being able to provide ample humidity to your plants is a crucial duty, especially in winter.

To make sure that you be able to do so, the ECO Farm Hydroponic Humidifier can work for 14-28 hours at a stretch. If you take the light cycles and dark cycles of indoor grow tents, that would be just a picture-perfect match anyway.

Based on the humidity work that the device is doing, it can easily cover a grow tent of up to 30m² of ground area.

Now, it's the most unique and standout feature of this device. And it's the 360-degree nozzle that rotates around its body. A coverage tactics of this sort will be ensuring a uniform distribution of humidity around the tent. Sometimes, growers come up with a tension of where to place the humidifier or so. With this feature enabled, you don't have to worry about that at all.

Among other significant features of this model, we got to mention the 8L water tank. Considering the capacity of this model, a 8L water tank can support the continuous operation of up to 28 hours. Also, the water tank is quite easy to clean.

With the favor of the classic knob control, you can adjust the mist output just as you want.

In case you want to make use of mini humidifier in your office, home or bedroom, ECO FARM HUMIDIFIERS would be a good choice over there as well.


The best humidifier for grow room is an important device that will allow your plants to grow in the right way.

Get a model that will suit the need of your room and the one that you can afford.