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Guide To Watering Your Cannabis Plants

Watering your cannabis plants the right way can make a big difference. This guide will help you understand how often and how much water you should give them. Furthermore, this guide will also go over which type of water can give you the very best results. Watering your weed plants is not as easy as it seems!  How much water a plant requires depends on many different factors:


The hotter the temperature, the more  you will have to water your cannabis. Beware! As plants drink faster, they can also uptake nutrients much quicker. Plants will thus become more prone to nutrient toxicity.


Humidity directly impacts water uptake. When there is less water in the air, more water will evaporate from the leaves, causing cannabis plants to uptake more water. In other words, the dryer the air, the more plants need watering.

Temperature For Denser Buds

Soil Composition

The composition of the soil plays a big part. For example, perlite, sand or coco coir will provide air to the roots and reduce the risk of over-watering. Yet, at the same time, you will have to water more often. By the same token, peat and vermiculite retain a lot of water so you will have to wait longer before you water again.

Cultivation Method

The cultivation method can greatly reduce water requirement. When growing organically, the soil life holds on to the water thus keeping the soil moist much longer.

Plant Size

Size matters. The bigger the plant, the faster it will drink up the water you give it. If your big plants are growing in big containers, no need to water too often. However, a big plant in a small pot will need to be watered much more often.

Type Of Strain

The type of strain that you grow plays a big part. For instance, a Moroccan landrace will need much less water than most modern hybrids. Indeed, Moroccan kif plants thrive in the Rif mountains where water is scarce in the summer.

The Number 1 Mistake

One of the major mistakes people make when it comes to watering is giving their weed plants too little water, too often. In a conventional garden, this can lead to killing the plants due to an accumulation of mineral salts into the growing medium.

It can also have negative consequences in an organic garden for 2 reasons:

  • First of all, most plants love it when you allow the medium to dry between watering. That is because it forces the plants to produce deeper roots so as to search for water and nutrients deeper into the soil. Eventually, these plants will end up with a healthier and larger root system which will help them withstand droughts and find nutrients more efficiently. When the soil remains constantly wet, it creates an over-watering situation. The oxygen present in the soil starts to deplete and the roots end up rotting.
  • Secondly,  watering your cannabis too often makes the growing medium  more likely to rot and more prone to pathogens like the seedling melting disease and pests such as fungus gnats.

What Does Over-watering Really Mean?

When a marijuana plant is over-watered, it starts wilting and the leaves become droopy. The plant will look like it is in dire need of water, except the container will be heavy and soaked.
Some plants grow in hydroponic systems with the bottom part of the roots literally growing under water. This is possible because over-watering per say doesn’t exist. It is rather a lack of oxygen that will suffocate the plants causing the roots to rot. It is harder for plants to recover from an over-watering than it is for them to perk up again after suffering from a lack of water. This is because when a plant is over-watered, the roots start to rot. To pull through, it will have to grow new roots.

How It Happens

Watering your cannabis profusely is not the issue. It is when the growing media is constantly wet that the plants start to suffer because the oxygen is lacking. Lower roots can naturally withstand a wet environment where the oxygen content is low but make sure the upper part of your medium can dry between watering. Watering your cannabis too often will eventually cause the roots to rot.

Monitoring The Moisture Level

An excellent way to know is to check by sticking a finger into the soil. If the first couple of inches are dry, it is time to water. Another great way is to weigh your pots. Finally, a water sensor in your container will tell you how moist the soil is so you will know exactly when to water.

Quality Water For Top shelf Nugs

It’s not just about how you water. This type of water growers use also plays a big part. Spring water, tend to be the best quality water for your cannabis. It is devoid of chemicals and also contains important minerals. Rain water is also pretty good too as it is untreated. Then, tap water can be okay but you will have to let the chlorine evaporate overnight before using it. 

The pH

The pH is a measure of acidity or alkalinity of a solution. It is highly recommended to check and adjust the pH of your water because it will allow plants to make use of all the nutrients the plants need. Take a look at our nutrient guide for more information about pH and nutrients. It’s important to note that in organic gardening, the soil life has the ability to regulate the pH on its own.
Digital pH Meter

A pH meter is a tool that measures the pH of the water. Water at the right pH will help plants make optimal use of nutrients.

How To Water?

Watering your cannabis sprouts

After sowing some seeds, it is great to use a water sprayer to gently moisten the soil without blasting water at high pressure. That way you do not dislodge the young sprouts. With seedlings, the soil cannot dry too much. Because their root system is shallow and weak, they cannot go without water for long. The soil has to be moist but shouldn’t be overly wet.

When using mineral fertilizer:

When you do water, pour water in until it comes out of the drainage holes. Make sure that the water comes out because the soil is saturated with water, not because it is too dry to absorb any of it. Water can save your plants from over fertilization (Leaching) and can also make your buds healthier and tastier right before the harvest (Flushing).

In organic gardening:

There is no accumulation of minerals so there is no need to water profusely to prevent nutrient lockouts. With this method, it is better to water less and a bit more often. Indeed, the beneficial microbes and fungi need the soil to be moist so they can thrive. If you are into organic gardening, you will have to be watering your cannabis more often then conventional growers.

Water your cannabis efficiently

The best way to water most plants is to water the soil directly from below the plant. It’s good not to apply water directly on the plants because it may trigger fungal diseases . Likewise, water drops can magnify the sunlight and burn your leaves. A gentle watering is the way to go since it will not splash water onto the plant. By the same token, the soil will have the time to absorb the water.