There are a number of changes to consider once plants go from the vegetative stage to the flowering stage:
Outdoors, flowering occurs naturally when the plant receives less light each day as summer turns into fall. Indoor growers can trigger the flowering cycle by reducing the amount of light marijuana plants receive from 16 to 12 hours a day.
Marijuana light cycle: 12 hours a day
The Spring Equinox is a good reminder that it’s time to kick off the outdoor growing process and start germinating your seeds.
Once your seed has germinated, or sprouted, it’s ready to be placed in a growing medium, like soil. The tap root will drive down while the stem of the seedling will grow upward.
If you need to determine the sex of your plants (to discard the males), they will start showing sex organs a few weeks into the veg stage. It’s imperative to separate males so they don’t pollinate the females.
Seedling stage length: 2-3 weeks
Within the flowering stage, there are three subphases:
The flowering stage is the final stage of growth for a cannabis plant. This is when plants start to develop resinous buds and your hard work will be realized. Most strains flower in 8-9 weeks, but some can take even longer, especially some sativas.
But that is just an average. The time it takes for weed to grow varies greatly. As mentioned, it depends on a number of factors and can range from 8 weeks to well over half a year.
Time Required: 0 to 4 weeks
That is unavoidable.
How Long Does It Take For Weed To Grow?
The flowering (or bloom) stage begins when you switch your lights to a 12 hours on and 12 hours off schedule and continues until harvest. As mentioned, your plants will double in size during this stage of growth.