marijuana weed flowering

Flowering in Marijuana

One of the most important phases in marijuana growth is the flowering stage. Those who grow marijuana will agree with me that it is seemingly the trickiest phase and if not given full attention it can result to a massive mess   on the crop. A lot is involved in relation to our plant’s sex, watering, humidity requirements, lighting, pH and even the essential nutrients. Many growers usually assume that it is a one grow phase. However, there are almost five stages that one can exercise to ensure that the marijuana plants yield maximumly. We will discuss them in detail.

Blooming phases

You can give your plants optimized nutrients in each subsection of the flowering phase to enable later harvests with more THC. Before we look at the stages, let’s acknowledge some vital tips.


When your plants look healthy, well-nourished and their height is around 20 inches, it is time to introduce the 12-12 hour system. This simply means that for 12 hours the lights should be on while the other 12 hours they should be off. This tricks the marijuana that fall has reached and it is time to begin budding(flowering).


We have to inspect our plants keenly during the flowering stage so as to spot and remove the male ones. They are characterised by their pollen sacs and they are banana-shaped. Make sure no pollen escapes in the process of eliminating them as this could ruin our whole crop. If the females are fertilised, they will start focusing on growing seeds instead of growing bigger buds. I believe no one would want to smoke seeds.


Humidity must remain below 45% at all times during the flowering phase. These low conditions of humidity are necessary so as to avoid the buds developing molds. Moldy buds are simply a wasted crop.

Nutrients and the pH

The ideal pH levels for marijuana plants is 6.5. Anything above or below this will lead to undesirable results. On the nutrient bit, you should stop the supply of nitrogen. At this stage, the plants need Magnesium, Phosphorus Potassium and a little bit of Sulphur.

marijuana flowering

Stage 1

Pre-flowering-At this stage, your plants may be showing their gender. It is even before switching the light system into 12-12. Female primordial flowers show up at the nodes. They only have two hairs at first. This usually happens after the root system is well set. Once you see the pre-flowers, you should now engage the 12-12 system.

Stage 2

Early Flowering-After changing the lighting system, early flowering will begin. The pre-flowers start turning into buds and then into early flowers. As more white hairs develop, the buds change building up resin glands and small support leaves. This stage normally lasts 1-3 weeks after switching to the 12-12 lighting system. Also, adding nutrients such as potassium and phosphorus at this stage will ensure a bountiful harvest.

Stage 3

Peak Flowering-Here, the buds become well developed and have a mature floral structure. It is at this stage that our plants put on many cannabinoids including THC. Potassium and Phosphorous are still essential and they will guarantee an increase in bud size, THC levels and even the weight. It is advisable to monitor your buds at this stage with a magnifier lens to see the condition of the resin heads, especially to be able to know the harvesting period. This stage usually lasts 2-5 weeks.

Stage 4

Late Flowering-This is normally one to two weeks to the harvest. Bud hairs and the resin glands start to reduce in number. Before harvest, stop all nutrients uptake and flush your marijuana plants to eliminate pollutants.


Therefore, we see that the flowering phase is complex and is directly related to a good/bad harvest. One should be very keen while tending to the plants at this phase.