Watering Marijuana Grown In Soil

Cannabis plants use a lot of water, and regardless of what sort of setup you’re using, you’re going to want to make sure you have plenty of H2O. There are no hard and fast rules when it comes to watering a cannabis plant since the requirements of the plant are determined by the environment it’s growing in. If the environment is very hot, the plant will use more water. If the plant is receiving the maximum nutrients, it can absorb.

Water acts a vehicle for dissolved nutrients and minerals, being absorbed through the roots before spreading through the rest of the plant. It also cools a plant down, fills up cells to keep the plant structurally sound, and is required for photosynthesis.

In general, water enough so that your soil is faintly moist, but not wet. If the soil is too wet, you risk fungal growth and root damage. In this article we’ll talk about the different ways water affects cannabis growth, covering the following topics:

Water Sources

water sources cannabis soil

The vast majority of growers water their plants from the tap. In fact, you might even have trouble finding reverse osmosis systems in a lot of hydroponics and gardening supply shops, depending on where you live. Some places are blessed with pure tap water. Most places in Europe and North America, however, are likely to have some impurities in their tap water, especially in large cities. While the severity of these impurities can vary, many growers crave precision in their operations, and tap water can carry with it unknown variables.

Most tap water will contain extra minerals. The type of minerals depends on your location. Calcium, sodium, and magnesium are common. The harder your water is, the more minerals it will contain, and there is a huge variety of potential minerals your water could contain.

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    When it comes out of the tap, your water could have an EC that ranges from 0.2 to 0.8, or even higher. The real issue here is that even when you take an accurate measurement, there is no way for you to know what sort of elements are in your water, and the ratio at which they occur. This means that all the extra money you’ve spent on expensive, carefully measured nutrients is for naught: the mix is instantly unbalanced by an unknown quantity of other nutrients. In a worst case scenario, this can cause nutrient burns or lock-outs and inhibit the growth of your plants. More info about your water in the articel “Hard or soft water for marijuana plants

    How Much Water

    How much water weed soil

    The amount of water you should use varies depending on the environment of the plant. It depends on the size of the plant, the temperature, the composition of your soil or substrate, the properties of the water you’re using, and the capacity of your air filtration systems. When your plants mature, the environment gets warmer and less moist, and the plants will greater air flow and additional water. Large leaves widen the surface area on which evaporation can occur. The metabolic process is activated by heat and transpired moisture is blown away, which causes the plant to transpire more. Check this Marijuana watering and feeding schedule for more info

    When To Water

    When to water cannabis on soil

    You need to keep soil moist from the very beginning of the life-cycle of the plant – before your seed has even germinated into a seedling. Since the seeds don’t have any roots, they will die if they dry out. At the same time, they drown in too much water. Usually, it’s advisable to keep seedlings and young sprouts hydrated by spraying or misting them with water, to help ensure you don’t drown them by watering them too heavily. Once the seedlings have rooted down, you can start to water them in earnest with a watering can.

    As the seedlings root down and develop, you can also let the soil dry out for brief periods of time. These short dry periods will help limit the risks of your soil developing any mold or fungal growth, which can sicken and destroy a seedling. Just remember to water the plant regularly, but don’t let the soil get too wet. Also, make sure the soil doesn’t get too dry, or your plant won’t undergo photosynthesis. Obviously, this will cause your plant to stop growing and die.

    Although many pots will come with little trays that retain the water you’ve already used for irrigation, you’re better off throwing that water out and using fresh water. Letting water sit for long periods of time is just begging for the accumulation of bacteria.

    If you water the plant with too much volume at one time or water the plant too quickly, tiny channels will form in the soil. Water drains quickly out of these channels, and it won’t be absorbed by the roots. Always water your plants slowly and evenly to ensure good hydration and distribution of nutrients. Also, make sure you are using room temperature water of ~20 degrees Celsius, otherwise the roots could experience thermic shock.

    The morning is the best time for you to water your plants. That way your plant has a whole day of sunlight and chemical processes it can use the water for. Watering in the evening increases the chances that you will have to deal with fungus or mold.

    Common Watering Issues With Soil

    Common watering issues soil cannabis

    The number one issue around hydrating plants is over-watering. Don’t do it. Make sure your substrate isn’t constantly soaking wet. If your soil is always wet, there are a whole host of issues that can arise. The roots can rot, the leaves can die and fall off, and that isn’t even mentioning the huge risk of fungal growth and mold. If you’ve been overwatering, stop ASAP and give the plant only tiny bits of water until the roots are white and healthy again.

    Also, try not to let your soil dry out too much. If a plant doesn’t get enough hydration, the plant won’t develop properly. Eventually, the cells will lose too much water and the plant will wilt and collapse. At that point, it’s very difficult for a plant to bounce back and recover.


    Soil nutrients for weed

    In soil, try to minimize your liquid fertilizer application to necessities. For example, if you have a bad soil mix or your growing container is too small, or the plant seems like it’s underdeveloped. Liquid fertilizers can be added to your water source before you water the plant.

    Liquid fertilizers are absorbed extremely quickly by the root system of a plant. The thing is, this isn’t always a good thing. Being absorbed so quickly means it’s very easy for you to add too much fertilizer, which can damage the plant. This double-edged advantage/risk is the reason you want to tread carefully when it comes to liquid fertilizers.

    You’ll also be able to choose between chemical and biological liquid fertilizers for your plants.  The biological liquid fertilizers usually work the best, and you don’t have to worry as much about toxicity or any long term damage to your soil or water. Unfortunately, most of these are algae-based and they have a tendency to be kind of stinky.

    You also have the option to fertilize the plant and provide nutrients through the stoma on the foliage. The pores on the foliage absorb nutrients quickly as well. Just spray a highly diluted nutrient solution on the leaves and then rinse the leaves off afterward with normal water.

    Thanks for reading. Please leave comments or questions below and don’t forget to download my free grow bible


    Avatar for Robert Bergman

    Robert Bergman

    Robert Bergman is an Amsterdam-based marijuana grow expert who has years of experience from small grows to massive operations. His passion for growing led him to develop his own Gold Leaf strain. Now, Robert is dedicated to sharing his knowledge with the world.... [Read full bio]


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