VWC Best Practices

Best practices when using VWC sensors with the Pulse Hub. VWC %, Water Content, and more.

John McLaughlin avatar
Written by John McLaughlin
Updated over a week ago

What is my ideal water content %?

Many users ask about their ideal VWC range. We're here to help! To put it simply, there is no ideal range. It will always change, even with the same plant.

The best practice for identifying your ideal ranges:

  • Confirm that your VWC sensor is installed correctly (VWC-1 User Manual)

  • Water the plant to its maximum (like you're doing a flush)

  • Wait 30 minutes for the readings to stabilize, and then once stabilized you have found your maximum water content

  • After you have found your maximum water content, you want to let your plants get quite dry (near the stage of drooping)

  • Once they've hit that stage, you've found your minimum water content before your plant will begin to experience stress

Keep in mind, these percentages will change slowly as the plant gets bigger and root mass develops.

Identifying your ideal ranges will help you set accurate alert thresholds in-app.

Ex: You found out that your max WC is 42% and your low is 18%, you can now set your alert thresholds for 20% and will always know when to water.

How & where should I install my VWC probe?

The most important thing to understand about VWC probe placement is that it matters less about what position you install the probe, but more important that this position is consistent across ALL of your VWC probes so you are comparing apples to apples.

IMPORTANT: VWC probes operate by sending electrical signals between the probe barbs. If ANY of the metal on the probe is exposed to anything besides the medium, you will get inconsistent data. This is especially important when running cloth pots, as they are too thick to get a good reading (anything thicker than rockwool outer plastic is too much). You can either make an opening in the side of the container so the probe makes full contact with the medium, or you can do a "top vertical" install as seen below.

Here are some examples of positioning along with their dryback curves for reference:

"What is crop steering and how can it improve my grow?" We have you covered! VWC is a crucial part in crop steering. If you're not familiar, we suggest checking out our Ultimate Crop Steering Guide!

Have a question? Reach out to us at support@pulsegrow.com or give us a call at 888-537-8573 during our business hours (M-F 9a-4p PT) so we can take care of you!

Did this answer your question?