How To Water Cannabis Plants

Here is a simple rule: Water less often, but when you do, water well! So rather than giving your plants only a little water, but too often, drench the entire medium completely, but less frequently. But how much water is sufficient?

A full drench means watering the entire substrate with about half the capacity of the container in litres. So, if you grow in a 4l pot, give 2l of water or more. As we discussed previously, exactly how much depends on a lot of things. Still, you should see about 10–20% of the water that you gave coming out of the bottom as runoff. The runoff will also flush out minerals that accumulate each time you give water and nutrients, reducing the risk for nutrient lockout and deficiencies.

Tip: Do keep in mind that if you’re using certain media, such as peat, the soil can at first be very slow to absorb water, and may even repel it until well-saturated. This means that if you were to water the substrate all in one go, most would simply run down the sides of the pot and out through the bottom. In such cases, slightly “pre-water” your substrate and wait for it to soak in. After 10 minutes, you can give the rest of the water. If needed, repeat. Do the “pot lift test” in between to see whether the soil has really absorbed your water.

DON’T LEAVE YOUR PLANTS SITTING IN RUNOFF

Along with your containers featuring holes at the bottom for water to escape from, the containers themselves should be lifted slightly off the ground so that all the water can drain and plants aren’t sitting in stale liquid. Drainage trays can catch this runoff, but should immediately be dumped after collection to avoid creating a breeding ground for bacteria, pests, and mould.

Watering cannabis plants seems like the easiest thing to do, yet many growers, especially those new to cannabis cultivation, make mistakes with watering. Overwatering is one of the most common reasons for all sorts of growing troubles such as nutrient deficiencies and cannabis diseases, although giving your plants too little water can also negatively affect their growth.

HOW MUCH SHOULD YOU WATER CANNABIS?

One issue with watering plants is that it isn’t really an exact science, and many different factors contribute to how much you should administer. As an obvious example, as your plants get bigger, their watering needs will change. But there are other, more complex variables that also determine how much or little you should drench your plants. Let’s discuss some of the most vital:

STAGE OF GROWTH

Unsurprisingly, the water and nutrient requirements of your plants will change as they grow and develop. A young seedling will take up much less water than a vigorous flowering plant with a large root system. This could mean that you water a small plant every 2–3 days, as opposed to once per day with a rapidly maturing plant.

THE IMPORTANCE OF PH WHEN WATERING PLANTS

If you are growing cannabis organically in soil, you shouldn’t need to worry much about the pH level of your water/nutrient solution. But for the majority of cannabis growers who are using common mineral nutrients and grow weed in soil, coco, or hydroponically, the correct pH level of the water is very important.

The reason for this is that cannabis plants have a limited pH window where they are able to take in nutrients. If the pH level of the water is either too high or too low, the plants are unable to take in nutrients even if they are present, a phenomenon known as nutrient lockout.

When you grow in soil, the pH range of your water should be 6.3–6.8. If you grow soilless (e.g. coco) or hydroponically, the pH level needs to be even lower, 5.5–6.1. To test your water pH, use a pH measuring stick or pH measuring drops. If the pH is too high or too low, use some drops of “pH down” or “pH up” to adjust your water to the right level. Most of the time, if you’re using tap water, your pH will likely be too high. Also, if you’re adding cannabis nutrients to your water, measure the pH first, then adjust it after you add the nutes.

BOTTOM LINE—WATER WELL, BUT NOT TOO OFTEN!

If you know how and when to water your plants, and are aware of any associated issues along the way, you can prevent most common cannabis growing problems. You will raise happy, healthy plants, and can look forward to fantastic yields!

Happy growing!

THE IMPORTANCE OF PH WHEN WATERING PLANTS

If you are growing cannabis organically in soil, you shouldn’t need to worry much about the pH level of your water/nutrient solution. But for the majority of cannabis growers who are using common mineral nutrients and grow weed in soil, coco, or hydroponically, the correct pH level of the water is very important.

The reason for this is that cannabis plants have a limited pH window where they are able to take in nutrients. If the pH level of the water is either too high or too low, the plants are unable to take in nutrients even if they are present, a phenomenon known as nutrient lockout.

When you grow in soil, the pH range of your water should be 6.3–6.8. If you grow soilless (e.g. coco) or hydroponically, the pH level needs to be even lower, 5.5–6.1. To test your water pH, use a pH measuring stick or pH measuring drops. If the pH is too high or too low, use some drops of “pH down” or “pH up” to adjust your water to the right level. Most of the time, if you’re using tap water, your pH will likely be too high. Also, if you’re adding cannabis nutrients to your water, measure the pH first, then adjust it after you add the nutes.

BOTTOM LINE—WATER WELL, BUT NOT TOO OFTEN!

If you know how and when to water your plants, and are aware of any associated issues along the way, you can prevent most common cannabis growing problems. You will raise happy, healthy plants, and can look forward to fantastic yields!

Happy growing!