Cannabis Growing – the Sign of Flowering Stage


There is usually a sign of the flowering stage before it begins so pay attention to your plants so you can time things well. The flowering stage is the final stage of growing before harvest. Marking when the flowering stage starts isn’t that difficult but we’ll break it down here. 

Cannabis plants need long hours of uninterrupted darkness to get into the flowering stage, which helps trigger flower growing but also expect your plants to at least double in size during flowering. When you grow indoors triggering the flowering stage is related to your photoperiod: set your lights to 10-12 hours of darkness to trigger flower growing. We’ll take a look at the 7-9 weeks schedule in this article.

For most cannabis strains, the flowering stage lasts approximately 7-9 weeks but this depends on the strain. So, this schedule, the 7-9 weeks, is not the same for every strain, it is just a general principle you can refer to. Let’s analyze the flowering stage of cannabis week by week and with a few tricks you will get a great harvest in the future.

Signs of flowering stage

Week 1: Plant Transition Vegetative to Flower – the Sign of Flowering Stage

To transition to the first week of the flowering stage you’ll need to shift the photoperiod to a schedule very different from the vegetative stage. During veg, you likely have been providing an 18/6 schedule but when we transition we want to convince the plant that winter is drawing near and that they need to start producing flowers. We do this by changing the light schedule to 12/12, which is closer to winter lighting. This will encourage female plants to grow flowers.

And although your plants have entered flowering, you still need to give them nutrients—but the amounts will be a bit different so be sure to research that.

Week 2: Identify the Sex of Plants – the Sign of Flowering Stage

During the second week, the white pistils will be shown on the female cannabis plants. These wispy white hairs are located on the crossing of big fan leaves and the main stem. These white hairs will become the buds, it is called cola.

People can identify plants’ sex by the white hairs, it is easy to separate the males from the females. If the plant is male, it will grow pollen sacs, if the plant is female, it will grow white hair. Identifying the sex of the plants is a must to do, cause the creation of seeds by male plants and female plants will highly affect the quality of cannabis.

Be sure to keep feeding your plants through this stage!

Week 3: Flowering Critical Stage – the Sign of Flowering Stage

During this critical stage, the female plants will start flowering by putting more energy into growing. They need to get appropriate nutrients and dosages. If the leaves of plants become yellow or they start to lose leaves pay close attention: it may be a natural occurrence during the flowering stage or it may be indicative of something more serious. Check our article for more information. If your plant is overfed you’ll know by checking the tips of the leaves which will be discolored and may start to curl depending on which nutrients they are getting too much of. It will also be worthwhile to flush your plants during this stage.

Week 4: Growth Stops and Plants Focus on Their Buds – the Sign of Flowering Stage

By this stage of flowering your plants have stopped growing and are putting all their energy on growing buds in the hopes of reproducing before winter arrives. Every day you’ll note that the buds are growing larger and the trichomes make a strong pungent odor. Increasing bud size may cause your plants to tip over so make sure you support your plants with some structure.

Week 5: Buds Increase in Size Even More – the Sign of Flowering Stage

As buds become thicker they start to dominate the plant. this is a good sign because it means your plant is in full flowering mode. The odor will be extremely strong at this time.

The color of the plant’s pistil hairs may convert from white to a darker amber color. At the same time, the trichomes may turn opaque. Dark hairs and milky white trichomes are good signs: they mean the plant is not far away from harvest!

Week 6-8: Flushing and Knowing When to Harvest – the Sign of Flowering Stage

There are different kinds of cannabis plants and they do not flower at the same time. Even though some plants can be ready for harvest in three weeks, some of them are not ready until week eight.

A good harvest cannot be finished without flushing. Flushing plants means removing nutrients by putting pH-balanced water into the soil after the plant stops being fed. A plant with no nutrients will always taste better because nutrients really change flavors.

Using a magnifier or jeweler’s loupe will help you check whether the plants are ready to be harvested. Observe trichomes carefully, If the color of trichomes turns from clear to milky white, it is the time to harvest. If the trichomes are still clear, it might be too early.

Budding Stages of Weed

Week Stages Details
1 Germination and Seedling Stage
  • Germination: Seeds sprout, and seedlings emerge from the soil.
  • Keep the soil consistently moist but not waterlogged.
  • Provide 18-24 hours of light per day using a low-intensity light source.
  • Maintain a temperature of around 20-25°C (68-77°F) and humidity of 60-70%.
2 Early Vegetative Stage
  • Seedlings continue to develop their first set of true leaves.
  • Continue providing 18-24 hours of light per day.
  • Begin feeding seedlings with a diluted nutrient solution, if necessary.
  • Maintain appropriate temperature and humidity levels.
3-4 Mid-Vegetative Stage
  • Plants grow more vigorously, developing additional sets of leaves and branching.
  • Increase light intensity if using artificial lighting.
  • Continue feeding plants with a balanced nutrient solution.
  • Monitor for any signs of nutrient deficiencies or pests.
  • Maintain optimal environmental conditions.
5-6 Late Vegetative Stage and Pre-Flowering
  • Plants transition from vegetative growth to pre-flowering.
  • Stretching may occur as plants prepare for flowering.
  • Continue providing 18-24 hours of light per day.
  • Adjust nutrient levels as needed to support flowering.
  • Monitor plant health and address any issues promptly.
7-9 Flowering Stage
  • Plants enter the flowering stage, and buds begin to form.
  • Adjust light cycle to 12 hours of light and 12 hours of darkness to mimic natural daylight hours.
  • Continue providing appropriate nutrients, with a focus on phosphorus and potassium for flower development.
  • Monitor humidity levels to prevent mold and bud rot.
  • Keep a close eye on plant health and address any issues promptly.
10 Ripening and Harvest
  • Buds mature and ripen during this stage.
  • Trichome development peaks, indicating optimal harvest time.
  • Monitor trichomes using a magnifying tool to determine readiness for harvest.
  • Flush plants with plain water if desired to remove excess nutrients.
  • Harvest plants when trichomes are mostly cloudy or amber, depending on desired effects.
  • Remember to adjust this schedule based on the specific requirements of your autoflowering strain and your growing environment. Regular monitoring and adjustments are

To Sum Up – the Sign of Flowering Stage 

If you have any questions, please don’t hesitate to reach out to us!

And be sure to check out our other blog posts for useful tips on becoming a great grower!

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