What Is the Ideal Temperature and Humidity for a Grow Tent - Backyard Boss
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What Is the Ideal Temperature and Humidity for a Grow Tent

If you’re considering buying a grow tent, or you have already bought one but you’re wondering what temperature and humidity it should have inside, this article will be very useful. Understanding these two things is crucial if you want your plants to grow properly in indoor areas. However, if you’re looking for something smaller to start your indoor planting adventure, check our recommendation of the best grow tent or the best mushroom greenhouses.

Every plant is a little different, and that’s why they need different temperatures and humidity. For this reason, it’s very important to know their specific requirements, before setting up your grow tent. With that being said, I would like to guide you now through some of the most common indoor grown plants, and their unique needs.

Ideal Temperature

Close-up of dew moistened tomatoes on vine
Image credits: kie ker via Pixabay

As I mentioned above, due to their specific needs, the ideal temperature inside your tent of each plant can vary significantly. Some of the plants require restrictive temperatures, while others can grow in a wide range without any problems. Try to grow together plants that have a similar ideal temperature for the best results.

It would be very difficult to list all of the plants in this article, however, below you can find the most common ones and the temperature ranges or ideal temperatures that are the most suitable for them.

  • Tomatoes – 55-85 F
  • Orchids – 65-75 F
  • Strawberries – 60-80 F
  • Lemon trees – 50-80 F
  • Orange trees – 55-100 F
  • Blueberry bushes – 45 F
  • Herbs – 55-70 F
  • Carrots – 55-75 F
  • Mushrooms – 60-70 F
  • Green Beans – 65-86 F
  • Bell peppers – 70-80 F
  • Onions – 55-75 F
  • Beets – 50-70 F
  • Radishes – 60-65 F
  • Lettuce – 60-65 F
  • Kale – 65-75 F
  • Arugula – 45-64 F
  • Swiss Chard – 86 F
  • Mustard Greens – 50-75 F
  • Yarrow – 65-70 F
  • Ginger – 77 F
  • Spinach – 60-65 F

Tips for Controlling the Temperature

The first thing you’ll want to do is to make sure you’ve got an accurate thermometer working in your grow tent. Once you’ve installed it, these things can help you regulate the temperature in your growing area. 

Use Exhaust Fans 

Grow tents should have vents in their construction, allowing you to insert an exhaust fan. This will help reduce the heat trapped in the grow tent while keeping air circulating throughout.

Keep Ducting Straight

The ducting for your grow tent may want to bend a bit – so be sure to keep it straightened out so that none of that hot air is getting captured.

Keep In a Cooler Room

Keep your grow tent in a room that isn’t too hot. The external temperature of the room can easily affect the temperature in it. If keeping the tent in a cooler room isn’t an option, use a window fan, exhaust fan, or other circulation sources to keep the air flowing in the room where the tent is kept. 

Or Use an Oscillating Fan

If your grow tent is being kept in a windowless room like your basement or a closet, add an oscillating fan into the mix. This will help to regulate temperatures in the room which, in turn, help regulate the temperatures in the tent.

Use Low-Temperature Grow Lights

Grow lights have to be bright, but that doesn’t mean they need to be hot. LED grow lights, are better for grow tents than any other grow lights, as they don’t produce so much heat. 

Keep the Light Schedule Regulated with Daytime

Daytime hours are simply hotter, so keeping your lights in line with an opposite timeline could help reduce the heat in the tent. In other words, have your grow lights on during the evening and overnight hours to reduce the heat that would otherwise accumulate with daylight hours.

Add CO2 to the Air

Adding some CO2 can help your plants do better if the heat gets a little high for them, especially since those grow lights need to be strong. The CO2 also increases and speeds up growth for most plants.

Ideal Humidity

Close-up of dew drops on white and yellow orchid
Image credits: Myriams-Fotos via Pixabay

Just like with ideal temperatures, ideal humidity in your grow tent will vary depending on the plant. It’s difficult to set up ideal humidity for all of the plants that you are growing simultaneously. That’s why try to establish the near-perfect humidity for the plants you’re growing and keeping together. If they vary too much, consider a second or even third grow tent for your indoor garden.

Below you can find the list of the most common plants and their ideal humidity to grow.

  • Tomatoes – 65-75%
  • Orchids –40-70%
  • Strawberries –65-75%
  • Lemon trees –50%
  • Orange trees – 45-50%
  • Blueberry bushes – 85-90%
  • Herbs –50-60%
  • Carrots –90-98%
  • Mushrooms –80-90%
  • Green Beans –60-75%
  • Bell peppers –85-90%
  • Ginger – 70-90%
  • Onions –65-70%
  • Beets – 98-100%
  • Radishes – 95-100%
  • Spinach – 95-100%
  • Lettuce – 50-70%
  • Kale – 95%
  • Arugula – 90-98%
  • Swiss Chard – 98-100%
  • Mustard Greens – 95%
  • Yarrow – 90%

Tips for Controlling the Humidity

These six tips can help you regulate the humidity in your tent.

  1. Avoid overwatering your plants if you’re trying to maintain a lower humidity level.
  2. Use a dehumidifier if you’re aiming to keep the humidity lower.
  3. Always remove stagnant water, it’s necessary whether you’re looking for high or low humidity.
  4. Add more fans to improve airflow and ventilation, it will keep the humidity lower.
  5. Purchase a small air conditioner for the grow tent if you find the temperature and humidity are consistently higher than your plants need.
  6. Plant your veggies and flowers in absorbent soil which will help trap moisture in, and prevent too much evaporating into the air.

Grow Tents Made Easy

These simple tips can help you keep the ideal temperature and humidity in your grow tent. A few simple appliances like fans or a tiny air conditioner, the right room, and keeping that ducting straight could be all that’s needed to keep your plants healthy and thriving.