Growing Cannabis in Hydroponics - 5 Tips

Posted on Oct 10 , 2020


In this article: Lighting and ventilating plants and the basics of caring for plants, harvesting, and post-care, whether you call them grass, cannabis, potted plants, cannabis, or other plants.

Whether it is a plant, cannabis, or other plants, if you know how to grow plants using hydroponics, it is easy to know how to grow plants quickly. Compared with growing in the soil, hydroponics can bring higher yield and shorter growth time, but it will initially cause trouble for beginners. Although most people think of growing plants in the water when they say "hydroponics", they will benefit from hydroponics when they absorb the nutrients they need directly into the irrigation water. The industry standard depends on the ratio of water to air. This article will show you how to grow cannabis in three to four months-perhaps the easiest method of hydroponics: hand watering in a soilless medium.

Basis of Method 1


1. If you have no soil farming experience, please consider growing cannabis in traditional soil farming. Planting in hydroponics is much more difficult than planting in soil: you have to optimize nutrition, light, and ventilation, and if you do not have prior knowledge, it may be somewhat difficult. Don't expect to increase from 0 to 100 from the beginning. Although it is easy to develop if you have the necessary knowledge, it usually takes some time to acquire information and knowledge.

On the one hand, other obligations may restrict you and force you to stop growing. If you are a beginner and want to try hydroponics, then you can succeed. Make yourself smart, but don't make friends or acquaintances. Nothing stops you faster than rumors about hydroponics.

Consider planting other hydroponic plants besides cannabis. Hydroponics does not mean that you can only grow cannabis. You can grow lettuce, tomatoes, and even mushrooms using hydroponics. Testing these plants will provide you with important information you may need when growing cannabis.

2. Obtain all necessary accessories. If you shop wisely, you should not spend more than $300 to $500 on five facilities and accessories. Each plant will get about 1 to 3 ounces. You need the following (for details, see "What Do You Need" below):

  • Cannabis seedlings or branches

  • White paint or aluminum foil

  • Hydroponic nutrient solution

  • Basin

  • Coconut fiber and other materials

  • Compact bulb with fluorescent light

  • Stopwatch

  • Soil pH test

3. Prepare the position. Plants need light to grow. This is a problem if you want to grow indoors. Many planting sites are located in dark corners, where light is absorbed rather than reflected. For the best growth effect, you should paint the walls bright white or cover them with white film.

  • Matte or off-white wall paint may be the simplest solution. The lighter the white, the better the glossy white will reflect about 55% of the light. Titanium dioxide is the most suitable.

  • High-gloss aluminum foil reflects very strongly, about 90%, so it is more effective than aluminum foil. However, since high-gloss films can reflect light and heat, effective indoor ventilation is very important.

Method 2: Lighting and ventilation

1. Assemble the bulb. They should be hung above the pot first and should be able to rise to the final height of the plant. There are countless ways to fix them, choose the right one. The easiest way is to hang them on a board on a shelf or fix them.

  • Clip-on bulbs are ideal for fluorescent lamps. The socket is included, so no installation work is required, and the housing optimizes light reflection. Any light that does not hit your plants will be lost.

2. Make sure that your lamp provides the absolutely necessary but optimal amount of light per square foot. Lumen is a unit of measurement for the amount of visible light emitted by a light source. Therefore, it is useful to consider the code number of the light source and the required code number. On average, the sun emits about 5,000 to 10,000 lumens of light per square foot.

3. The minimum minimum value for medium-sized plants is 3,000 lumens per square foot. Note that the actual lumens reaching the plant may vary depending on the distance from the light source and the reflectivity of the surrounding area.

4. The ideal amount for normal growth is 7,000 to 10,000 lumens per square foot.

5. To know the number of lumens received per square foot, divide the total lumens by the total area. If you have about two 300-watt bulbs, each with 40,000 lumens, and the size of each bulb is 3 x 3 x 2 feet, then your total lumens will be 80,000 and the total area will be 18. 80,000 / 18 = about 4,400 each Square foot lumens.

  • Make sure your plants are not burned or overheated by the light source. Adequate light can make your cannabis grow, bloom and prosper. The ideal temperature is 27°C to 29°C, and the maximum temperature is 32°C. Below, you need a small heater, fan or cooler to achieve ideal growth conditions.

7. Ventilate the room. Good ventilation is absolutely essential for healthy plants. For example, if your room is in a closet, you can only use a small fan. The piping system is very useful in the box.

  • To create a duct system, just use a 6-inch fan (looks like a hamster fin) for simple cooling to avoid temperature rise and unpleasant smells.

  • In any case, the fan will increase its strength as the plant stem grows.

Method 3: Plant

1. Sprout your cannabis seeds. To make seeds, first, moisten them with a large paper towel and then wrap them. Put another layer on top to avoid drying out. Alternatively, you can put wet paper towels in a sealed plastic bag and store it in a dark, warm place for at least 24 hours.

2. After the seed germinates, place it in a piece of asbestos. Rock wool is an excellent material for growing new cannabis plants. When the sapling begins to grow identifiable roots, it can be placed in coconut fiber.

3. Water the plants with mixed nutrient water (filtered water or tap water). Make sure the pH is 5.5 to 6.0. First, dilute the nutrient solution at a ratio of 1:4 and increase it to 1:1 within a week or two. Overnutrition is a typical beginner's mistake and can damage plants. Most foods have instructions for use, and you can usually follow them without hesitation.

  • You can use Nutrition Night. There are many nutrient solutions on the market. If you are not sure which plan is right for you, please consult a merchant. First, add the nutrient solution to the water, and then adjust the pH to 5.5 to 6.0 to ensure the best nutrient supply.

Method 4: Take care of plants


1. After the coconut fiber surface is dry, water the plants with pH-optimized water and nutrient-rich water. At the end of the growth cycle, water once a day.

  • After watering, make sure that at least a few drops of excess water flow out of the plant container so that unused nutrients will not accumulate in the planting material. When watering, coconut fiber, and pearls sometimes do not become too little or too little, but you will need to adjust the watering method according to the water demand of the plant.

2. Keep the cannabis plant in the growing period until it reaches half of the desired final height. You can achieve this goal by lighting for 18 to 24 hours a day.

  • After marijuana sowing, there are two main growth stages, namely vegetables and flowering. Depending on the stage, the plants should be treated differently. During the germination stage, growth is at the forefront. In order to maintain this stage, they need at least 18 hours of lighting a day. This will simulate many days of "summer". There can be up to 24 hours of light in a day, preferably 18 to 24 hours.

2. Plant height is usually the decisive factor in determining how long it should be maintained during the germination period. During the flowering period, the height of the plant can double, so it makes sense to keep it in the vegetative period until it reaches half of the required height. If they grow in a closet, they should be kept in a vegetative state until they are 6 to 18 inches tall.

3. Once the plant reaches the right height, the flowering period begins. Switch to a shape of 12 hours of darkness and 12 hours of light to make the plant bloom, thereby making it bloom. This simulates the beginning of autumn.

  • During the flowering period, plants shift their attention from growth to flowering. You must signal the start. In the wild, as the days get shorter, cannabis plants begin to bloom-a sign of winter. To simulate these situations, you need to change the lighting mode, let the bulb burn for 12 hours, and then leave it for 12 hours.

4. Choose male plants. It may take one to two weeks after changing the lighting scheme to determine the gender of the plants. You should delete all-male plants because they will fertilize the female plants and concentrate the energy on seed production instead of THC. You can smoke fatty cannabis, but it contains less active ingredients.

  • You can determine the gender of the plant after changing the light mode for one to two weeks. Female plants have white hair, while male botrytis can grow into pollen sacs. To optimize yield and avoid fertilization, all-male plants should be removed. If the male and female plants are together, the female plants will produce many seeds instead of cannabis. On the other hand, male plants do not produce cannabis, only pollen.

5. Please be patient when the plants mature during the flowering period. For beginners, this is usually the most difficult task. The flowering period can last six to twelve weeks or more, depending on the type of cannabis you grow.

6.Change the irrigation water to pH adjusted water one to two weeks before harvest. Otherwise, you can taste the taste of food in the form of a chemical aroma.

  • At the end of the flowering cycle, some older leaves may turn yellow and fall. This is completely normal and it indicates that your plant is absorbing nitrogen from the leaves and storing it in the buds-this is the closest signal to harvest time. Now stop providing nutrition in the past one to two weeks to achieve the best taste.

Method 5: Harvesting and post-processing

1. Collect mature plants by cutting whole plants or removing individual flowers piece by piece.

  • There are many ways to determine the correct harvest time. Basically, 50% to 75% of white hairstyles/hair turns brown.

  • The other method is based on capillaries or resin glands-is it white milk or already half white/half brown?

  • The marijuana harvested earlier looks more hallucinogenic, while the marijuana harvested later mainly has a relaxing effect. Try what you like most.

2. Cut the plants so that the leaves do not stick to the buds. The leaves will make your final product have a slightly lower THC content and bitterness-so they do not belong to the variety. You can use them for shreds, butter or green dragon.

3. Hang the cut flowers upside down in the shade and let them dry until the flowers open under pressure.

4. Store the flowers in an airtight container, and then store them in a cool place to allow them to mature for two weeks to one month. Open the jar every day for air exchange to remove moisture. Moisture is the enemy of post-processing and can cause mold, so be sure to dry the flowers carefully.

What do you need

  • Cannabis seeds or branches

  • The high-quality nutrient solution for hydroponics.

  • Planting pots. I recommend a pot size of 1 to 5 gallons, depending on the size of the planting area and the amount of growth required. Remember that you need to water the plants more frequently in small pots, and large pots need more light.

  • Coconut fiber (preferably mixed with perlite in a ratio of 1:1), which can be bought cheaply online.

  • Fluorescent lamp (CFL). You can buy a 42-watt bulb from your online store for about $10, and you will need at least two per unit to start.

  • All bulbs have enough bulbs (each piece costs less than $5 and already has a fixing clip).

  • Timer check light. It ranges from $5 to $30 and requires a timer at the beginning of the flowering period at the latest.

  • pH tester. You can find them in the pet store in the aquarium section, but it makes more sense to use special plant equipment (still under $20).

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