The flowering stage is when your cannabis plants grow their aromatic and soon-to-be-smokeable buds. This is a particularly important stage in your cannabis plants’ life cycle. A lot happens in the flowering stage; learn how to care for your plants through every week of flowering.
When the light cycle provides your cannabis plants with longer hours of uninterrupted darkness, they enter the flowering stage. Your plants will stop growing and instead put their energy into producing buds (flowers). Outdoors, this will normally happen when the days get shorter around the end of summer. When you grow indoors, flowering will begin once you switch your lights to 10-12 hours of darkness.
In week 5 of flowering, you can observe the buds all over your plant becoming thicker. You may also spot new buds growing in new places such as along the main cola. With buds abounding, your cannabis plants will get fatter every day. This is a surefire sign you are in full flowering mode. At this point, your plant will have a very intensive odour. Ensure that you have a good ventilation system in place if you grow indoors or in a region that doesn’t allow for legal cultivation.
At the locations on the plant where you previously saw some hairs, you can now see the first signs of real buds developing. There still won’t be many resin glands and trichomes on your plants, which means that the smell won’t be too pungent yet either.
For most cannabis strains, the flowering period will last about 7-9 weeks, although some sativas require even longer for their buds to mature.
As your plants become more picky, you should check for potential deficiencies that could manifest in various ways, such as discoloured, yellowing leaves or loss of leaves entirely. At the same time, you should also check your plants for signs of possible overfeeding (“nutrient burn”) that could show up around this time as well. Nutrient burn will usually show in the tips of the leaves becoming discoloured. If this happens, you need to cut down on feeding.
At week 4 of the flowering stage, your cannabis plants will likely have stopped growing altogether and are now spending all their energy on growing buds. There will still be white hairs sticking out from the buds, but the buds themselves will become bigger and fatter with each day. With more and larger buds growing, your plants will now produce more trichomes, making the odour a lot more noticeable at this stage.
With the stretching of cannabis in early flowering, you may possibly want to think about training techniques such as low stress training (LST). This is where you bend the stems down and away from the centre of the plant so you can get an even canopy for a more efficient use of your grow lights. This can help you obtain much better yields later on.
While your plant is putting in quite some overtime to gain size and height, she will grow a number of new leaves mostly at the top of the main colas. Your cannabis plant is busy growing “green stuff,” like leaves and stems so she can become stronger and sturdier.
What happens during the flowering phase of cannabis? Learn about flowering week by week. This guide will help you maximise flower production and THC content.
In the case of pure indicas, during the stretch period they will usually only double their size. If you start with 30cm plants these will end up with a height of around 60cm at the end of the stretching period.
The graphic shows the different nutrients that the plant requires and the difference between one type of nutrient or another (nitrogen, phosphorus, potassium or calcium) depending on the stage of the plant.
Indica/sativa cannabis hybrid
In the case of sativas, it’s important to remember that these plants can as much as quadruple their initial size, meaning a 30cm plant can finish at 1.20m in height. For this reason, when it comes to very long flowering sativas with a significant stretch as mentioned, the plants can be started at 12/12 from germination, avoiding excessive vegetative growth. They can also be pruned and trained if you want to grow in SCROG with fewer plants per m2.
The flowering period of indica plants is always shorter than that of sativas. This means that an Indica needs a higher concentration of nutrients to provide the maximum flower production. With sativas the opposite is true, with more weeks of flowering, the lower the amount of nutrients required weekly although if we check the total at the end of the crop both plants will have used almost the same amount of liquid fertiliser.
33 days, the structure is created, now the buds begin to fatten
45 days, buds are fattening with the resin building up
Here’s a graph from Aptus that explains the plants nutrient requirements according to the week of life.
The stage between switching the photoperiod to 12/12 and seeing the first flowers appear is known as “the stretch”, as plants will tend to elongate and stretch in growth at this time. There’s a huge difference between the stretch of an indica plant and that of a sativa.
Without a doubt, flowering is one of the crucial stages in cannabis cultivation. In this article we tell you everything you need to know about the blo