Water appearing on top of leaves

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Water appearing on leaves, What’s going on ?! Do they sweat? thumbnail

What’s going on? Are they sweating? Is it bad?

Hi there and welcome (back) to Free The Tree!
In today’s article we’re going to covering those weird water spots that can appear on the top of your leaves, generally over night. If you’re worrying don’t! (spoiler alert) it’s just the condensation of the leaves sweating 😉

Here’s what we’re going to cover if you want to jump straight to what you’re looking for

Why does water appear on top of leaves?

The very short answer… your plant is just sweating and that extra water had nowhere to go 🙂

Water generally appears on top of leaves during the night cycle. It is likely that you have a full grow room with leaves close or touching each other. You open your tent in the morning and what do you notice? Little areas with water on your leaves

As you may know Cannabis, like all plants, sweat; And they do so through their leaves. Most of the time we don’t notice it since it’s such small amounts of water and it dissipates right away.

But.. when 2 leaves are close, or touching each other, that sweat can’t dissipate anywhere. It starts to accumulate and condensate, and that is what you’re seeing!
Basically, it’s like dew, water condensing on your leaves.

Why does this happen more at night time?

There are 2 reasons. The first, at night the temperatures are lower and the humidity level is higher. This makes the evaporation process slower.
The second, cannabis sweats a more during its respiration phase.

This water is simply the condensation your plant naturally sweats.

Water appearing on my leaves – Is it bad?

A little water on your leaves in the AM, that dissipates within the hour, no problem. You may want to defoliate a bit to give your plants some room, but the bit of water itself is not issue.

But if this is all over the foliage and it doesn’t evaporate during the day, it can amplify the light and over time. This can create light burn issues on your leaves and mold issues on your flowers and stems.
I doubt you’re in this situation

How do you avoid Water appearing on top of leaves?

The main case scenario is that your leaves are too close to one another. To solve the “problem” your have to give them some room.
The goal is to stop the overlapping of leaves so that they have the room to breath.

Couple ways to reach this goal :

Add a fan to help with the air flow in your room
Keep an eye on your humidity levels, especially if the water doesn’t evaporate
If you don’t have one, or cut it at night, add an extraction fan; It will help reduce the humidity levels
Increase the temperature in the room. By heating up the air the humidity levels will drop and fix the problem.
Move the leaves around to give them room. You can tie them loosely to make sure they avoid touching
Prune some leaves, a bit radical but it can be necessary if your grow room is over-filling with foliage. You don’t want to get mildue problems.

Generally, removing one or two leaves and moving others around will do the trick. For a more wide spread issue, adding a fan, ventilation system or an extraction is very helpful;

If your plants are really close one another and most of the leaves are touching ventilation alone might not be enough. Try pruning leaves or moving around the plants to get more spacing.

A very high density of plants will also raise your chances to see mold appear once you have flowers.

Side note – Can you spray your leaves with water or nutrients ?

A quick side note to this article, on a closely related subject. Foliar feeding or just spraying your leaves with water.
In itself, water on leaves isn’t an issue at all and can be good. The plant can hydrate and absorb some nutrients they need right away.
After all, it rains outside and your plant gets wet, no problem at all

The real issue can come when they’re wet for too long under the grow light. To take our “nature example”, when it rains you generally have clouds (right?) reducing the light intensity.
The water acts like an amplifier of light.

With a long exposure, or high light intensity, it can burn your leaves, and that sucks.
if you need to spray your plants with water solutions, do it ~15 minutes before lights out

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Alright folks, That’s it for this! Hope hopefully this helped you understand why water appears on top of Marijuana Leaves , if not send us a message and we’ll try and get you some advice ASAP!
Until next time, be safe and grow easy!

About the author

plant-lover

Plant Lover is Free the Tree's founder and a passionate grower of plants. Mostly from the city, I work on my computer all day so about 4 years ago, on my off time, I started growing to have some more green in my life. I never imagined I would fall in love with botany and discover so much about this plant. Since then I keep learning everyday, meeting new awesome people of our community and which keeps me growing constantly You can always get in touch with me on our Instagram!