What Should Your Humidity and Temperature Be in a Spacebucket?

Beginner Grow Guide is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. If you click on a link on this site that takes you to Amazon, I will earn a small commission and help keep the lights on at no extra cost to you 🙂

For those who are looking into growing their own cannabis, there are a number of different builds to begin vegetating and harvesting your plants. Aside from your typical outdoor or shed style grow rooms, indoor growing has become an easily controllable and discrete method for growing cannabis.

While many may dedicate an entire room, closet, or tented area, an alternative ‘spacebucket’ method has become an increasingly popular method for indoor growth.

With an all-in-one contained lighting, watering, and ventilation system, these are speedy and compact buckets for individual plants. This allows for elevated levels of control over one plant for newer growers, or for experimentation by more seasoned cannabis producers.

Marijuana Plant in Soil Held in Front of Indoor Garden

Because of the heightened level of micromanagement for your bucket, there are some recommended conditions for a healthier and potent yield. Below we’ll touch on the ideal levels of humidity and temperature for your spacebucket, as well as the ways to monitor and adjust them.

The Ideal Humidity Levels and Temperatures

Once you have built your bucket and germinated your seeds, it is time to target in on the correct atmosphere for optimal plant health. Compensating for drier in-home conditions and temperature fluctuations throughout the various seasons will leave you with a moving target, however, there is an ideal destination.

The Correct Humidity Ranges

In terms of humidity, the ideal range should be 45-55% relative humidity during the vegetative stage. When your plants begin to flower, lowering your relative humidity to about 35-45% is recommended.

Relative humidity is the percentage of water vapor needed to saturate your plant at a specific temperature. As the temperature changes, so will your relative humidity, which subsequently enforces the importance of the link between these two conditions.

If the humidity is too low, your plants will dry out or simply have ineffective growth. If your humidity is too high, mold can easily grow on the inside of your spacebucket or on the plants themselves.

Obviously, keeping your relative humidity in check will prevent these problems, but how do you adjust it?

Ultrasonic humidifier in the house.

If you notice that you are outside of the ideal humidity range, there are a couple of methods to remedy this problem. The simplest method would be to implement a humidifier or dehumidifier around your spacebucket.

Although it is the priciest option, it will give you the most control over the conditions. In addition to a humidity and temperature monitor, of which we will expand upon below, these are the two most important external devices to adjust the atmosphere within your bucket.

Other DIY methods of adjusting humidity include:

Increasing Humidity

  • Wet sponges inside your enclosure
  • Cups/dishes of water

Decreasing Humidity

  • Lowering temperature with cooler lighting systems
  • Increasing ventilation fan output

The Ideal Temperature

When measuring your temperature, the enclosure should fall between 70-80° F (or 21-27° C). These numbers may be slightly altered for differing strains, so you may find ideal temperatures outside of this range.

As with humidity, the interior temperature is a fluid number that can be affected by a number of conditions. The lighting in your spacebucket will obviously dictate the majority of heat output, but external factors such as air conditioning, heating, seasons, climate, and room elevation can all sway your temperature.

There are two main components when adjusting the temperature inside your enclosure: your ventilation airflow in and out, and the heat output from your lighting system. While direct lighting is a key component for proper growth, if temperatures go too high you can prevent proper photosynthesis.

Ventilation Grille, Extractor Fan

Choosing ‘cooler’ lighting systems such as LED lights can lower the internal heat without affecting the necessary light output.

In addition to lighting, increasing your airflow will exhaust some of the hot air while supplementing cooler air from outside the enclosure. This is simply adjusted by speeding up or slowing down your fan speeds within the ventilation system.

Other Tips to Control Temperature

  • Run your lighting at night when surrounding temperatures drop
  • Increase air conditioning in your home
  • Use a space heater if your temperatures drop too low

Tools to Monitor and Control Humidity and Temperature


As mentioned above, humidifiers can be an easy and simple way to increase the relative humidity inside your spacebucket. By placing a standard in-home humidifier within range of your intake fans on your bucket, this will easily supplement any vapor discrepancies.

While your humidity levels may be fickle, it won’t require an excessive amount of supplementation. The watering of your plants and heat from your lights will get you within reach of the suggested levels, so small adjustments will suffice.

No products found.


Similar to above, dehumidifiers will act the same way in the attempt to reduce relative humidity. With increased exhaust fan output, a dehumidifier will absorb the excess water vapor and store it within its reservoir.

It is best to run your dehumidifier on a cycle, which will avoid overly drying the air surrounding your spacebucket.

No products found.

Humidity and Temperature Monitor

A simple thermometer/hygrometer combination monitor will provide both the temperature and relative humidity inside your bucket. Small and non-intrusive, these can be easily placed in your enclosure.

For more experienced users, you can also implement similar tools as an automatic controller for external devices. This will let you select a range of acceptable relative humidity and temperatures, and in turn will adjust fans, humidifiers, and dehumidifiers.

No products found.

Final Tips

For the most part, following the standard lighting and watering guidelines for your strain will get you within reach of an acceptable humidity and temperature range for your plants.

Marijuana plants. Green cannabis

Implement some of the above-mentioned techniques when looking to fine-tune your spacebucket conditions. Your plants will subsequently thank you with a healthier and more potent yield when it comes time to harvest.