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How Long Does It Take To Grow A Marijuana Plant Indoors-Part II

From the previous blog, we learn that there’re five stages of cannabis growth, they are:

  1. The germination stage
  2. The seedling stage
  3. The vegetative stage 
  4. Flowering stage 
  5. Harvesting stage

Depending on your cannabis strains and the growing method you use, these stages can last up to 3 or 5 months on average. Here is a breakdown of these stages of growing indoors. 

Step 1. Germinate the seeds: 12 hours to 8 days

The first marijuana growth stage is the germination stage. It can last for 12 hours or 8 days. A typical mature cannabis seed should be dry and hard in texture. It should also be dark brown. If the seeds are green or white in color and somehow soft, then they are underdeveloped seeds and may not germinate even under the best conditions. Ensure your seeds are mature and easy to germinate. Alternatively, you can use clones and skip the entire germination phase. 

Once the seeds have sprouted, you can transfer them to a growing medium such as soil. You can grow them in pots or on the ground inside your grow tent. The plant will develop a tap root that will go deep into the soil as the stem springs upward. 

From the stem, two round-shaped cotyledon leaves will sprout up as the plant springs free from the seed’s protective casing. The new delicate leaves will draw insufficient light the plant needs to grow healthy and strong. As the roots continue to grow, the plant will produce its stalk, followed by buds. At this point, your cannabis plant is now a seedling. Throughout the germination stage, your plants will need an uninterrupted light cycle of 16 hours per day. 

Step 2. Seedling phase: 1 to 4 weeks

Once your cannabis plants have grown into seedlings, they will develop lots of cannabis fan leaves. At first, the leaves will have only a single rigid blade which will culminate into many more blades as time goes by. By the time your plants complete the final growth stage, they will have produced an average of 7 blades per leaf. However, some cannabis strains may develop more than seven blades per leaf.

If you notice your cannabis seedlings are dark green with a vibrant look, then they are growing normally and are healthy. This is also a good indicator that they are receiving sufficient light. However, it would be best if you took care not to feed your plants excess water while in the seedling phase. This is because the small roots only require a minimal amount of water to thrive.

It is also in the seedling phase that your marijuana plant is susceptible to disease and mold. Therefore, always keep your grow space clean and regulate the temperatures to ensure no excess moisture in the growing environment. Furthermore, ensure the plants receive sufficient light. The average light required in the seedling stage is 16 to 18 hours of light per day. Therefore, ensure you have the best type of grow light to help your plants survive this delicate stage. If you’re not sure about choosing the best grow light, kindly contact us or visit our shop: Shop

Step 3. Vegetative phase: 3 weeks to 6 months

Your cannabis plants will begin to grow effectively in the vegetative stage. When your transplanted seedlings reach this point, they start to develop roots and foliage more rapidly. The vegetative stage is also the time to begin training and topping your cannabis plants. It’s also when your plants require a lot of water around the stock and roots, so you should increase their water intake. 

After 3 weeks in the vegetative stage, the roots will stretch outward, at which point you should concentrate on watering in the soil away from the stalk. This will enable the roots to spread out more efficiently and absorb water, soil and nutrients. When in the vegetative phase, your plants need healthy soil rich in nutrients, so ensure they receive sufficient nitrogen. 

A few weeks into the vegetative phase, and your plants will start producing sex organs. This is the ideal time to determine the male vs female sex of each plant, and get rid of the males. Getting rid of the males in the vegetative phase is significant in preventing them from pollinating the females. In this stage, your plants also require uninterrupted quality light (DIL), so ensure you provide not less than 18 hours of light each day.

Step 4. Flowering phase: 6 weeks to 3 months

The flowering phase is the final stage of the growth of a marijuana plant. Once the plants start flowering, they will develop reisin-like buds, indicating they are healthy, fertile, and with promising yields. Most autoflowering strains start flowering when they are 6 or 8 weeks old, but most Sativa strains typically take a longer flowering time.

If grown outdoors, the plants will naturally start flowering as they absorb natural sunlight. This transition is perfect at the end of summer and the onset of Fall when there is less sunlight. However, you can trigger and accelerate the flowering phase of your indoor grown plants by reducing their light cycle from 18 hours a day to 12 hours.

The flowering phase also contains three different substages, which are the flower initiation period, the mid flowering period, and the late-flowering or ripening stage. The flower initiation period can occur when the plant is 2 to 3 weeks into the flowering stage. At this point, the plant continues its average growth, and the females start to produce pistils, the pre-flowers, that enable buds’ development. 

In the mid flowering stage, your cannabis plants cease to grow, and the newly-developed buds grow thicker and fuller. This phase occurs at the 4th or 5th week of the flowering stage. By week six, your plants will enter the final period of the flowering phase, which is the ripening period or flowering time.

In this phase, the plant’s trichomes increase in density, and the plant develops a sticky texture. When this happens, be sure to pay close attention to the changing colors of the pistils, as this will help you determine if the plants are ready for harvesting.

Step 5. Harvesting: 1 to 5 days

The time needed to harvest cannabis plants varies from one grower to another and the existing conditions necessary to grow cannabis. For instance, harvesting is normally done in Fall for outdoor grown plants. However, indoor plants can be harvested any time of the year since they don’t depend on natural environmental conditions to grow. 

Once your indoor plants attain maturity and the harvesting stage, then it is time to reap the fruits of your careful and delicate labor. The only challenge is knowing when your plants are ready for harvest and how to do it carefully. Early or late harvest may affect the smell, taste, and potency of your marijuana produce. 

Once your plants leave the flowering stage, observe the changing colors of the pistils of your female plants. If the pistils turn slightly brown, then they are ready for harvest. On the other hand, if they are too brown, then your plants are overripe, and you may have missed the crucial moment when you should have harvested them. 

An easier clue to help you ascertain if your marijuana plants are ready is to observe the leaves and stem of the plants. Yellow leaves indicate that the plants are ready for harvesting. Swollen stems and yellow leaves that fall off suggest that the harvest time has passed, and it’s too late to salvage your plants. At this point, your weed will be too bitter and the smell unpleasant, making it worthless. Therefore, the earlier you harvest them, the better.

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