How Often to Water Cannabis

If you are an avid cannabis gardener and care for your plants like parents care for their children, this article will take you through the intricacies of watering your cannabis not just to keep it alive, but also to make sure it is a healthy crop.

You should generally water cannabis every 2 days. However, this can change depending on various factors, so let’s take a look at them now!

How often to water cannabis seedlings in soil?

Cannabis seedlings need to be watered when the soil is dry. The soil could dry out in under a day or take a few days, depending on the weather and whether you’re growing outdoors or growing cannabis indoors in soil.

You might think you could tell when the soil is dry just by looking at it but that’s a mistake! It may still be damp underneath the dry topsoil, which means it doesn’t require water just yet.

To correctly judge whether the soil around your seedling is dry or not, take a thumb or finger and stick it an inch (2.5 cm) into the soil. If it feels wet, you can hold the water for now.

Novice cannabis growers tend to overwater their seedlings by watering them regularly and not when the soil is dry. This can prove to be a fatal mistake. The excess water completely submerges the baby roots and prevents them from acquiring any oxygen, causing the plant to wilt.

Similarly, some cannabis growers will underwater their plant out of fear about the damage overwatering can cause. You should know that underwatering is as detrimental as overwatering. The roots begin to die if they are starved of water for long.

Should I mist my seedlings?

You can definitely mist your seedlings but the question is when?

Misting at the wrong time can damage your plant, such as when the weather is humid and there is no sun to dry the excess water. Night-time misting will also cause your plant to rot. And when the sun is out shining on a hot day, misting will create water droplets that act as magnifying lenses, focusing the sun rays on the leaves and burning them.

The best time to mist is in the morning, an hour or two before the sun comes up, so your plant can absorb the water without getting burnt. If there’s dew, it is preferable to shake it off so that it does not impede water absorption.

You can also mist your plant when the sun is setting. The warm temperature at this time allows perfect absorption of water while also making sure the leaves dry off by the nighttime, which prevents your plant leaves from rotting.

For people who have their plants indoors, the lights are analogous to the sun outdoors. Therefore, when misting plants indoors, it is important to raise and turn off the lights while the mist dries off. You can read about the best LED grow lights for growing indoors here.

If you have a small number of plants, you might find it easier to move the plants out of the grow room (and the light) and mist them.

How often to water cannabis during flowering?

You should water cannabis during flowering when the soil is dry (just like you would water cannabis seedlings in the soil).

However, your plant will become thirstier when it is sprouting buds and require more frequent watering.

Initially, a cannabis plant that is flowering will not require additional water compared to its grown but non-flowering counterpart. However, as the buds begin to develop and increase in size, forming pistils and calyces, your plant will start taking up more water.

By the way, if you’re not sure about plant development, you can read our blog on the 5 key stages of a marijauna plant.

As a rule of the thumb, the greater the number of growing buds, the higher the water requirement for your cannabis!

How much water does a cannabis plant need per day?

The amount of water per day needed by a cannabis plant depends on multiple factors, such as the size of the plant, temperature of the environment, and the composition and drainage of soil.

Size

Bigger plants have bigger leaves, which increases the surface area from which the plant loses water every day through transpiration. Therefore, bigger plants require more water compared to seedlings or smaller plants.  

Temperature

When the outdoor temperature is high, cannabis — just like any other plant — needs more water compared to when it is growing in relatively milder temperatures. This is also true for plants that receive direct sunlight. Plants that receive more sun grow faster and require more water to fulfill their growth needs.

Drainage

The medium that your plant has been planted in determines the amount of water needed to a large extent.

Cannabis grows well in airy, loose soil that does not hold a lot of water. Such soil mediums need more water compared to soil types that are not as airy and porous.

If you’ve planted your plants in another soil type, it will require less water because soils that are not porous tend to hold water. However, as these soil mediums retain moisture for long periods, they can cause the roots to rot!

When is the best time to water my cannabis plant?

The ideal time to water cannabis plants is in the morning or evening. In fact, this is true for most other plants!

During these times the sun is not at its brightest, so water does not evaporate and is actually used by the plant. Watering in the morning also allows the plant to dry off during the day, which is important as it does not leave moisture during the night. This prevents several diseases (like mold) that thrive in damp settings.

If you’ve been watering your plants at the wrong time and are worried about mold, you can read our guide on how to get rid of mold on weed.

Watering in the evening helps the plant to cool (after being in the sun during the day), and still allows sufficient time for it to.

Now you know how often to water your cannabis!

There are many factors that affect how often you should water cannabis, but the bottom line is to make sure that the soil is dry between watering spells. People will tell you that you should water your plants every 2 days but this might be a mistake depending on where you’re located and what your growing conditions are.

Also, remember that proper watering is only part of the game. To get high-quality cannabis, you should also take into account how much daily light your plants would need, how to properly dry weed, and  what are some of the best seed banks to source seeds from.