Maximize Houseplant Growth: Understanding and Managing Vapor Pressure Deficit (VPD)

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One method for achieving rapid growth in houseplants is to bring the vapour pressure deficit down as low as possible (VPD). The phrase “vapour pressure difference” (or “VPD”) refers to the pressure difference that exists between the amount of moisture that is now present in the air (which is referred to as “vapour pressure”) and the maximum amount of moisture that the air is capable of holding at a given temperature (saturation vapour pressure).

When the VPD is high, the air is dry, which leads to a significant amount of transpiration in the plant. Transpiration is defined as the process through which a plant loses water through its leaves. This could lead to wilting and a delay in the growth process.

If you are new to this blog my name is Ashley and I am a soil scientist. I am located in a Canadian Zone 3 and a USDA Zone 4. I write articles, make YouTube videos, Instagram & Facebook posts all designed for Canadians and Cold Climate gardeners using science-based methods. If you are looking for anything specific be sure to let me know in the comments down below.

There are a variety of actions you may take to guarantee that your houseplants have the highest potential VPD, including the following:

  1. Take note of the relative humidity of the air inside your home. Using a hygrometer, check to see that the relative humidity in your house is between 40% and 60%.
  2. Utilize a humidifier in the drier regions of your home in order to increase the relative humidity there.
  3. Collect the plants into a cluster. Plants are able to increase the relative humidity in their immediate area by exhaling moisture through their leaves.
  4. Maintain a consistent routine for watering the plants. Both underwatering and overwatering can result in an increase in the VPD. Underwatering can cause the water in the soil to become stagnant while overwatering can elevate it.
  5. When arranging plants, make sure to take into account the flow of air and the sources of light. Maintaining correct posture can assist in reducing the amount of moisture lost via perspiration by reducing the amount of direct sunlight and draughts that are experienced.
  6. Utilize a fan to help circulate the air throughout the space. This can help to reduce the VPD since it speeds up the processes of transpiration and evaporation.

By having an understanding of and being able to control VPD, you can ensure that your houseplants are able to grow swiftly while also remaining healthy. Keeping proper levels of VPD in the soil can help prevent a number of issues, including the dropping of leaves, wilting, and a slowdown in the rate of plant growth. If you take these recommendations into consideration and maintain the appropriate temperature, lighting, and watering levels for your houseplants, you will give them the best possible chance of thriving.