Chapter 17

Get Your Water

Home growers typically water indoor cannabis plants regularly about 1x, 2x or 3x a week depending on a factors. They include how big the plant is, how hot the environment is, how thirsty the plant is and how much water is given at each watering. Based on these varying factors, there is no one-size-fits-all watering schedule to follow.

Beginners should also know that they shouldn’t spay (“water”) the leaves of the plant with a spray bottle. That’s only done erroneously in the movies. As a home grower, you will water the the soil, not the actual leaves of the plant. So if you’ve been visualizing yourself misting the plants with water, be prepared to let that daydream go. Later on in the book, you’ll learn how to water your cannabis plants in every stage of the plant’s growth. For now learn about water options so you can choose your water source with confidence.


Tap water is OK for cannabis plants in soil.

It is totally fine to use tap water to water your cannabis plants in soil. If it is safe for humans to drink, it’s going to be OK to give to your plants.

You will however need to determine the ph of your tap water and adjust it accordingly if necessary. Ph is important because in order for the plant to uptake the nutrients it needs, the ph needs to be around a certain level. If the ph is too high or too low and the plant isn’t able to uptake nutrients, it can get stunted and produce weak branches, small leaves, and overall lose its ability to produce high quality flowers. It can also produce severe discoloration and browning of the leaves which is a result of nutrient deficiency.


Test the ph of your tap water.

Since you’re growing in soil, the target ph level is 6 to 6.8. It is actually recommended to fluctuate the ph between 6 and 6.8 over different watering sessions.

To get a ph reading, use a simple ph test solution kit, and then proceed to raise or lower it with “ph down” or unsulfured plant molasses as needed.

To use the ph test solution kit, fill the cylinder up halfway with water and then drop 3 drops of ph test solution, place the cover on, and then shake. After 3 seconds of shaking the cylinder, then you can evaluate the color of the liquid. “Yellow” or “Yellow with a hint of green” are the target colors you want to see because they represent 6 to 6.8. If the color is green or blue or aqua, the ph level is going to be too high and you’ll need to bring it down. Use the “ph” down product or unsulfured plant molasses to lower it. If you go too low by mistake, just pour some out and or add more tap water to balance it out.

It is highly unlikely you will experience any negative or problematic plant issues from using tap water.


Bottled water is OK for cannabis plants in soil.

The bottled water brands suitable for cannabis include Aquafina, Dasani, Crystal Geyser, Arrowhead, Voss, or Smart Water. The best mineral water option for cannabis is Evian. All of these brands are simply recommended because their ph levels are around 6 – 6.8 or a little higher. Avoid other water brands unless you search online for their ph level to confirm the ph is between 6 – 6.8. Some bottled water can have a ph reading of 8 or 9, so be sure to check it out before purchasing.


Marc Eden’s DIY Cannabis Cultivation Book For Beginners
Published by Green Carpet Growing, Inc.
San Diego, CA 92103
© 2021 Green Carpet Growing, Inc
All Rights Reserved

No portion of this book may be reproduced in any form without permission from the publisher, except as permitted by U.S. copyright law.

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