How to Water the Cannabis Plant?

Watering plants! What’s the rocket science behind it? I can do it anytime! Not as easy as you think! There is a science and technique behind watering cannabis than simply adding water to your plants. If you wish for a bountiful weed harvest every year, you want to find a sweet spot between watering cannabis plants. 

Over-watering may lead to nutrients washed away and root rot, while under-watering will not let plants absorb minerals- both will cause sickened plants. To prevent this, we will explain how to water cannabis plants and how much.

My Cannabis Plants need a lot of water. How much should I give them?

Cannabis has high water requirements like wheat, soy, etc. They need watering regularly, as it may wilt and die. It may not seem like the plant consists of 80% and above water required for photosynthesis. 

Based on research conducted by the Emerald Growers Association and Mendocino Cannabis Policy, cannabis plants require approximately 6 gallons of water per day during the growing season (June to October). Indoors, it requires approximately 3 gallons of water per day per plant. You should wait until the soil completely dries before watering again.

It is a general rule to follow for the farmers and growers, but you need to look for the dehydration signs your plant gives you, like light wilting, weak branches, pale leaves, dry stems, etc., and set a watering schedule. 

It is simple- Experience comes with time. So, you need to record the data and water schedule based on variables, climate, temperature, humidity, and other events to know what works best for you.

Also Read: What is the Best Soil for Growing Cannabis?

How often should I water my Cannabis Plants?

If you are growing cannabis indoors in containers, you might likely water it every 2-3 days. Outdoors or plants grown in soil require watering once a day or twice, depending on the weather conditions. To know this, take a finger test. Touch soil with a finger, if damp, wait for a day. As plants grow, you will know, how often you require watering your cannabis plants. Generally, in containers the soil is wet for 2 days or more. 

Remember, the watering frequency depends on various variables like climate and surroundings, whether you are growing indoors or outdoors, and size and growth stages, including environmental factors like humidity, light, temperature, etc. Let us discuss them:

1. Growth Stages

Do flowering plants have different watering requirements than vegetative plants? Yes, cannabis plants have different water requirements in each phase till maturity. When it’s seedlings, the roots are delicate and require water lightly and frequently (every 2-3 days), keeping the soil moist but not soggy. When it reaches the vegetative stage- the plant grows rapidly and requires high water. 

Water thoroughly when the top inch of soil dries out (every 3-5 days). The flowering stage demands less water as bud development takes priority. Water it when the top 1-2 inches of soil dry (every 4-7 days). 

As the plant grows, you require more and more water, but whatever the growing phase is, remember to wait till the soil dries out before repeating the procedure. 

2. Growing Medium

Cannabis thrives with the right balance of moisture and aeration at its roots. The type of growing medium you choose plays a pivotal role in this, as each has different water storage and drainage properties. Cannabis love rich and airy soils with good drainage systems. That is why containers must have drainage holes for the water to escape as water clogging may lead to rot and moldy roots. The more compact the soil is, the more moisture it will retain. Here is the short view of growing mediums watering schedule:

• Soil: Holds moisture well, but drainage is crucial. Water thoroughly until runoff appears, then wait for the top inch to dry.
• Coco Coir: Dries out faster than soil. Water more frequently (every 1-3 days) with smaller amounts to avoid oversaturation.
• Hydroponics: No soil is involved in hydroponics, so water needs are based on the plant’s size and transpiration rate. Frequent adjustments are typical.
• Perlite or Clay Pebbles: Perlite allows the water retention capacity of the cannabis, reducing the watering schedule. Adding clay pellets as a top layer helps in reducing water evaporation in soil.
• Rock wool: Rock wool is a great alternative to soil when growing weeds indoors. The material has excellent water-holding capacity and good drainage, causing less watering.

You can check water drainage by answering a question- Does your plant take a few minutes to drain water or 3-4 days to dry your soil? The longer it takes, the more likely there is a drainage issue causing stunted growth and other underlying problems. For improving drainage, use perlite to improve the drainage system of your pot.

3. Container Size

The dimensions of the container play a vital role in water and nutrient absorption in marijuana. If you have a small plant and a big-sized container, nutrients will not reach the plants, and vice versa, leading to plant suffocation. 

As larger pots hold more moisture, water frequency decreases with pot size. A seedling in a large pot might only need water every week, while a mature plant in a small pot might need it every other day.

Related: Choosing the Right Container for Growing Cannabis: Maximizing Quality and Yield

4. Temperature, Humidity, and Light Intensity

The amount of water your cannabis plant needs depends on temperature, humidity, and light intensity. Watering is more demand during hotter weather and intense light. Conversely, cooler temperatures and lower light mean less water usage- so you can ease up on watering.

How much does humidity impact watering needs? Humidity plays a vital role in water conditions. Despite the difficulty of understanding the correlation, high humidity slows evaporation, so your plant won’t need to be watered as often. Conversely, low humidity means faster evaporation and a thirstier plant. So, when the humidity is low in your region, water plants twice a day.

5. Cannabis Plant Health

Does the watering technique affect the potency of cannabis? Optimal watering practices contribute to overall plant health, which indirectly affects potency. Stressed or unhealthy plants due to underwatering or overwatering, will have lower potency. However, specific watering techniques like bottom watering likely have minimal direct impact on cannabinoid production.

Also, A stressed or unhealthy plant may show signs of underwatering (wilting, drooping) even if the soil is moist. Address the underlying cause and adjust watering as needed.

6. End Use

THC production tends to be higher with slightly drier conditions during flowering. Also, cannabis strains CBD are water intensive. However, don’t prioritize bud potency over plant health. A healthy plant will produce a good yield. 

7. Indoor vs. Outdoor Crops

When growing marijuana indoors, environments are more controlled. You can tailor light, temperature, and humidity to optimize water usage. Outdoor plants are exposed to elements, like wind, humidity, and rain affecting water needs. Monitor your plants closely and adjust watering based on weather conditions.

Watering frequency depends on the germination and growth stages. Also, overwatering is a common issue in this regard. If the environment is not too humid or dry, avoid frequent watering to avoid rotting. Also, during the germination stage, it may lead to late or no sprouting.

Also Refer to: Where to grow Cannabis- Indoor or Outdoor?

What are the signs of overwatering and underwatering Cannabis Plants?

Overwatering and underwatering cannabis plants pose similar signs, making it crucial to understand. Here is how to know the problem:

Overwatering initial signs might be wilting or drooping, but the leaves may also feel heavy and discolored. They might turn yellow or brown, starting from the lower leaves and progressing upwards, and have stunted growth and a weak appearance. The stem might feel mushy, and the soil will likely feel damp and soggy. You might even notice fungus gnats hovering around the pot. You can solve this issue by absorbing excess water with a paper towel, maintaining drainage holes clear, and waiting until the soil dries.

In Underwatering leaves start wilting and drooping, but feel dry, crisp, and brittle instead of heavy. They might also curl at the edges. Discoloration, if present, will usually start from the tips and edges of leaves, progressing inwards. Also, the plant will appear dry and lifeless, soil will feel dry and crumbly with slowed or stunted growth. Lower leaves might be the first to yellow and fall off.

Remember, underwatering can sometimes lead to wilting that initially mimics overwatering. In this case, the soil dryness and the overall condition of the plant will help you differentiate. If unsure, it’s always better to err on the side of underwatering and wait a bit before watering again. 

Also Read: How to Fix Cannabis Curled Leaves?

What is the best time to Water Cannabis? 

The best time to water cannabis is in the early morning before sunrise (5 AM to 6 AM) or in the evening after sunset ( 6 PM – 7 PM). Evaporation increases on hot days, and watering in the afternoon increases perspiration as water droplets magnify sunlight, causing tissue damage.

A drip irrigation system might help eradicate the manual watering process. Adjust water frequency and flow rate as per weather conditions. It is even better for large-scale outdoor weed cultivation.

What are the signs that tell your Cannabis is thirsty?

There are many signs your cannabis plants give you if it is thirsty, like:

• Visual signs: Look at the leaves! Are they wilting, drooping, or curling? It’s time to water. In the early stages, leaves might become slightly limp and lose their vibrant green color. Also, the plant might start looking dry and lifeless. It may become stunted and fail to produce new growth.
• Check the Soil: Stick your finger an inch deep into the soil and see if it’s dry. Don’t overwater, wait for a day or two and try again. By this, you will know how much and what frequency your cannabis plant requires.
• The Weighing Pots Method: Experienced growers can opt for this method.  If you’re comfortable handling your plants, lift the pot. A significantly lighter pot than when it was well-watered suggests the plant has absorbed most moisture.

If you are unsure about all the methods. Simply, get a moisture meter that will tell you the exact moisture levels so that you can adjust accordingly.

What’s the best way to Water Cannabis?

There is no single best way to water cannabis, as the ideal method depends on your setup and preferences. Here’s a breakdown of popular watering methods to help you choose:

1. Hand Watering: The most traditional and easy method is to directly water the soil with a watering can or hose until runoff appears. It allows for easy water flow and targeting specific areas but can be time-consuming for larger grows.
2. Bottom Watering: It is an ideal way of preventing overwatering where you water in the roots. For this, place the pot in a tray filled with water and allow the plant to absorb water from the bottom through capillary action. It is perfect for pots with proper drainage. It also helps in reducing the risk of fungal infections.
3. Spraying: Often used for seedlings and clones with delicate root systems, it is the best method during germination. A gentle mist helps maintain moisture without saturating the soil but is not suitable for mature plants, as it doesn’t reach deep roots. 
4. Wick System: It is a method where a wick (rope or fabric) continuously supplies water from a reservoir to the bottom of the pot. It is simple to set up and is best for small-scale projects, but monitor it.
5. Drip Irrigation System: Provides a steady flow of water directly to the root zone through emitters. Highly efficient and ideal for large grows, but requires initial investment in equipment. It is the best way for outdoor methods to save water.
6. Ebb and Flow (Flood and Drain): This cyclic system floods the growing tray with water, saturates the pots, and drains the excess. It provides excellent control over moisture levels but involves more complex equipment. It helps nutrient absorption and air circulation through roots, resulting in better yields.
7. Soaker Hoses: Slow-leaking hoses are porous hoses placed on the soil surface, releasing water gradually. Effective for outdoor grows in long rows, it prevents water wastage and excellent hydration but requires good soil drainage. It may not be suitable for container plants.

Also Read: Germination Guide

What type of water should I use for Watering Cannabis Plants?

What do you think about this? The right kind of water should be pesticide-free, proportional pH, have fewer minerals, etc. Let us see what should be the ideal water characteristics for cannabis plants:

• pH Balanced: Cannabis needs a slightly acidic environment with a pH between 6.0 and 7.0 to bloom. Ideally, aim for a pH of 6.5 in the soil. Water outside this range can make it difficult for plants to absorb nutrients, hindering growth.
• Contaminant-Free: Avoid using water with high levels of chlorine, chloramine, fluoride, or heavy metals. These can harm your plants or alter the pH.
• Low Mineral Content: Very hard water with high mineral content can build up in the soil over time, affecting nutrient uptake. Consider using rainwater, filtered water, or tap water that has been allowed to sit for 24 hours to allow some chlorine and other gasses to dissipate.

Some options for watering your cannabis plants can be regular tap water, rainwater, distilled water, or RO water, but should be at room temperature, and you need to be consistent with your watering routine. 

But people are confused- Can I use rainwater or recycled water for watering cannabis plants? Yes, rainwater is a great option if it’s clean and free of pollutants. Rainwater can be slightly acidic, so you might need to adjust the pH bit upwards. But remember to use recycled water that is greywater from showers or sinks and free of harsh chemicals or soaps. Test the pH and mineral content before using.

FAQs:

1. Should I water the leaves of my Cannabis Plants?

Avoid directly watering the leaves of your cannabis plants. While misting can be helpful for seedlings and clones to maintain humidity, it’s not necessary for mature plants and can promote fungal diseases. It is good to focus on watering the soil as roots will absorb and do the job.

2. How can I improve the drainage of my Cannabis Plants?

To improve drainage, use pots with adequate drainage holes. For soil growth, choose a well-draining potting mix with perlite or coco coir added for better drainage and aeration. You can also use clay pots as they are more breathable than plastic containers and help with drainage, but they also dry out faster, so adjust watering accordingly.

3. My leaves are drooping but the soil feels moist, what could be wrong?

There are a few possibilities that are leading your cannabis leaves to droop, like nutrient deficiency, root rot, or temperature stress. You need to monitor plants to know the problem behind plant weakness.

4. How much water do seedlings need compared to mature plants?

Seedlings and clones have delicate root systems and require frequent light watering to keep the soil moist, not soggy. Water every 2-3 days, adjusting based on the environment. 

Mature plants with established root systems require more thorough watering, allowing the top inch of soil to dry out between waterings every 3-7 days, depending on factors like pot size and environment.

5. Are there any strains of cannabis strains that are more drought-resistant?

Yes, some cannabis strains are known for being more drought-resistant. These are often Indica-dominant strains that have evolved to succeed in harsher climates with less water. Examples include Afghan Kush, Durban Poison, and Purple Kush.

Conclusion

The most common query we get from cannabis growers is how to grow healthy cannabis by optimal watering. The answer lies in the variants mentioned above. 

Water your cannabis plants- not too much, not too little, and not too often. If you understand the physics behind it, even if you are a beginner, you will not be less than a pro grower. 

Remember to purchase high-quality seeds from a reputed seller and monitor your plants. We are sure you will raise a healthy plant with an abundant harvest!