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How to Treat Underwatered Cannabis Plants

Last updated: April 14, 2021

underwatered plants 2
The most common anxiety for new growers is most likely the amount of water that their plant needs to thrive.

Usually, they think the plant needs more water, but they accidentally over-water their plant, then they swing back in the other direction and under-water it. This is very common and very sweat-inducing.

However, the reaction to err on the side of caution and stop watering a plant so much is actually a good one. Chronic over-watering can cause much more difficult problems to alleviate than a dry plant. So, how can we tell what our plant needs?

Symptoms of Underwatered Cannabis Plants

Changes in leaf colour and posture are the big ones. They should be bright green and perky, if they start to become yellow and droopy, they are still not getting enough H20.

Checking the moisture content of the soil is also a good way to make an assessment, even before the plant begins to show symptoms.

yellow cannabis

Credit: Pexels

Cannabis plants need a cycle of wet and dry to thrive. As the soil dries out, the plant’s roots pull in oxygen. If it’s too wet for too long, they’re basically drowning. However, they still need some water to survive.

Stick a finger into the soil, a few inches, and see if it’s dry. If it’s still wet down there, then the plant most likely does not need watering yet.

Look out for drooping or yellowing leaves and bone-dry soil deep into the pot, otherwise don’t water yet.

Take note, that a lot of these symptoms are very similar to when a plant outgrows its pot. If the plant has been growing a lot lately, it may be time for a transplant.

How Much Should You Water Cannabis?

It’s almost always better to under-water cannabis plants than over-water them. Issues such as root rot occur from too much water sitting in a pot for a long time and can decimate a plant. A thirsty plant can be fixed by simply allowing it to drink.

As a plant grows, its need for water increases as well. Put enough water into the plant’s pot for it to cool slightly on the surface for a moment, before being absorbed.

watered cannabis plant

Photo by Esteban Lopez on Unsplash

If the soil is currently very dry, water may flow through the drainage holes. If this occurs allow it a moment to absorb before watering again and keeping doing it until it stops leaking out the bottom.

Another great tip for figuring this out is to simply pick up the plant. If it feels lighter than usual, it might require water!

The watering schedule will vary dependent on the plant and its stage of growth, so getting a feel for each plant may take time but will eventually seem more consistent.


Underwatering a plant is a perfectly normal issue that can be alleviated through careful attention and only watering when a plant needs it.

Setting up a timer is a great idea to try to keep on schedule, though be cautious that the frequency of watering may increase as the plants get larger and begin to flower.

Never over-water and try not to under-water. Follow that motto and the plant will grow just fine.

Underwatered Cannabis Plants

Photo by chrisbeez on Pixabay

Featured Image: Sam Doucette on Unsplash