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what is the best temperature to grow cannabis

What is the best temperature to grow cannabis

As an example, let’s say your grow room is at the normal optimal day-time temperature of 75 degrees Fahrenheit (24 degrees Celsius). To reduce internodal length growth you will want to try to maintain the temperature at 71 degrees Fahrenheit (20 degrees Celsius) at night.

In a standard, well ventilated grow room the optimal temperature tends to be between 24-29 °C (75-85 degrees Fahrenheit). There are other factors that can warrant higher temperatures. For example, if you are enriching your cannabis crops with extra carbon dioxide then you will need higher temperatures for it to be efficient, usually around 30-32 degrees Celsius (86-90 degrees Fahrenheit).

Another important factor to consider during the flowering phase is that total bud size is largely impacted by the average daily temperature. It is important you make sure that temperatures do not drop below their day and night optimum; doing so will cause your buds to grow less than their potential.

Temperature is a very important factor to consider when growing cannabis. The temperature of your grow room will have an effect on the rate your plants photosynthesizes – the process in which they turn carbon dioxide, water and light into food. If your grow room is at the incorrect temperature, your plants will not be able to photosynthesize efficiently, thus negatively impacting the rate at which they grow.

Extra Tip: Reducing the night temperature to 62-66 degrees Fahrenheit (17-19 degrees Celsius) for the last two weeks of flowering will trigger the production of anthocyanin. This will really bring out the color of your buds making them look much more appealing. This is usually done once buds have reached their maximum size and you have started the final flushing process. It is not essential however, and can be overlooked if it is not practical – it is purely a cosmetic consideration.

After the initial 2-3 weeks you can reduce the night-time temperature back to its original 71 degrees Fahrenheit (22 degrees Celsius). This will stop the plant getting stressed. If there is a zero difference between night and day temperature for more than three weeks, your plant leaves may begin to discolor due to leaf chlorosis.

This technique is most effective during the first 2-3 weeks of the flowering period – when you have just switched to a 12/12 photoperiod. This is when cannabis plants put a lot of effort into their pre-flowering growth, creating the building blocks for their colas. At this phase, you will want to consider increasing the night-time temperature to match the day-time – this will really minimize the massive internodal growth associated with this time period and allow your cannabis plants to focus on growing much denser buds. Look at it this way, what use is extra stem to you? Surly you would rather your plants direct their energy into bud growth rather than throwing it away with longer stems?

What is the best temperature to grow cannabis

Because cannabis cuttings root best in warm conditions with high humidity, the cheap trays with clear plastic domes work remarkably well. In cool conditions, a heat mat should be placed underneath the trays to maintain an optimum temperature of 74-78 degrees F. and relative humidity at 75-85%. No matter where and into what medium you plan to root your clones, keep warmth and high humidity on your priority list. Clones allowed to get cold or dry will perish quite quickly. Too much humidity (over 90%) can also cause mold and rot, so cut a quarter-sized hole or two in your clear plastic dome to allow some air movement and circulation.

Ideal grow room temperature and humidity varies depending on the stage of plant life. Cloning requires higher temperature and humidity than vegetative growth and flowering plants have different ideal atmospheric conditions as well. In order to master the art of marijuana growing, dialing in the proper environment at the right time remains the most essential ingredient for success. So, what is the best grow room temperature and humidity level?

The best grow room temperature during the flowering stage of growth is 68-75 degrees during the day and no more than 10-15 degrees cooler at night. If you’re supplementing with CO2, daytime temps can be as high as 75-82 or so. During flowering, you should lower your relative humidity to 35-45% and even lower (30%) for the last couple of weeks before harvest. This will help you avoid issues with mold, bud rot and PM (Powdery Mildew) that can arise in higher humidity.

The Vegetative Stage: Best Grow Room Temperature

Garden temperature is a critical factor in photosynthesis and plant development.

The drying room is a place that must be carefully monitored. Keep in mind that your plants will be giving off a large amount of moisture into the room as they dry. It’s important to pull wet air out and keep air circulating in the room without actually having fans blowing right on your hanging branches, which can dry them out prematurely resulting in a harsh taste and burn. Also, growers in dry places such as Colorado struggle to extend their drying time with humidifiers, while farmers in more humid climates such as Northern California use dehumidifiers to pull water from the air in order to avoid mold growing on their buds.

Measuring and Changing Temperature and Humidity

The best grow room temperature during the vegetative stage of growth is 70-78 degrees F. when the lights are on during the “daytime” and no more than 10-15 degrees cooler at “night” with a relative humidity of 45-55%. With these settings, your plants will best be able to convert light into energy for growth. This is the time when the plant puts on leaves and branches and expands it’s root system throughout your growing medium. If it gets too cold or hot, growth stops and you eventually risk losing your plants altogether.

In order to properly measure temperature and humidity, you’ll need a thermometer and hygrometer. Best to invest in a digital one that can give you current readouts as well as highs and lows when you’re not inside the room. To raise heat, you’ll need a heater and to lower heat, you’ll need an air conditioner. These can be outside or inside the growing space depending on the size of your space and how much the temps and moisture levels fluctuate. A humidifier and a dehumidifier can be employed to raise and lower humidity rates. Larger grow rooms can benefit from a controller that uses a sensor to keep track of temps and humidity and turns on the appropriate appliance to regulate and keep them within your set parameters.