As a grower of marijuana, you already know that the success of your cultivation is measured by the amount of and quality of your crop at the end of the growing cycle.
If you are an outdoor grower you will be reaching that point about now as summer enters its final weeks and the days grow shorter. Outdoor plants will naturally recognize their time to enter the flowering stage, which is actually determined by the hours of darkness and not the amount of daylight. This is a factor to bear in mind and if the nights are still not dark enough you may wish to help your plants by shielding them from light by covering them or a greenhouse with blackout sheet.
For indoor growers, there is a much simpler solution by just maintaining a 12 hour on 12 hour off light cycle.
As you have just spent a lot of time and effort in nurturing your plants to the flowering stage it is really important to follow some basic rules to ensure that your plants provide the highest possible yield and quality, which will determine their potency and flavor.
Here is a very basic list of factors to take into account during the flowering stage.
As your marijuana plants begin to enter the flowering stage you will need to adjust the levels and type of nutrients you use to feed them. But don’t rush into doing this too early. Your plants will still need nitrogen as they are still growing but as the flowering stage progresses you will need to introduce phosphorus and potassium. You can read more about nutrients here.
The flowering stage is hard work for marijuana plants. They are still growing but at the same time putting a lot of effort into producing buds. That is why you should continue to use a vegetative formula until you are sure your plants are entering the flowering stage and then switch to a flowering formula.
One final point here is that you should stop using nutrients altogether in the final weeks as they can have a detrimental effect on flavor.
Now is a good time to check your plants and remove any male plants. It’s not uncommon for a hermaphrodite to develop during the flowering stage. These plants have male sex organs that will pollinate your female plants. So check again during the flowering stage to be certain.
You may well have specifically purchased “female seeds” so think that you will not have a problem, but mistakes happen so checking to ensure a rogue male has not crept into your crop is recommended.
If you do spot a male flower, recognizable either by a clearly male pollen sac or a yellow banana-like shape, remove the entire bud site to ensure no pollen escapes. Just one could fertilize your entire crop.
Pruning is often a matter of preference as some growers will recommend never pruning whilst others will say it is good for the plant and will improve the strength and quality of the buds. If you decide to prune then do it with care to ensure you don’t damage the plant in the process.
Leaves that are discolored should be pruned as they will continue to draw strength from the rest of the plant even though they themselves are dying. If you do find yellowing leaves as well as removing them look for the reasons why as this might mean a deficiency in nutrients, or some other problem that you will need to correct.
Temperature and Humidity
As well as changing nutrients and lighting you should also ament the levels of both humidity and temperature during the flowering stage.
During the 12 hours of light, keep temperatures between 68ºF and 77ºF (20ºC and 25ºC) near the foliage and 68ºF (18ºC) at the roots. Remember, higher temperatures require accordingly higher levels of carbon dioxide. When the lights are off and the plants are in the dark, you can let the temperature drop down to about 68ºF (18 degrees Celsius).
At the beginning of the flowering stage, try to lower the humidity to around 40-50%. You can drop it to 30% or more the second month to force the buds to produce more resin. The humidity must remain below 50% during the flowering stage, so use a dehumidifier if necessary.
When to Harvest
Possibly the most difficult aspect is the temptation to sample the flowers before they are really ready. The exact moment to harvest is a combination of experience and knowing the strain you originally planted.
Some signs to look for when making the decision are:-
- At least half of the pistils on the plant are red, you are ready to harvest.
- Resin that is thick, and easily visible to the naked eye
- A plant that is very heavy with buds, with some of the leaves turning yellow.
- Trichomes that are mostly white and milky. You can see these with a microscope or magnifying glass.
Of course, the time to harvest will also depend on whether you are growing outdoors or indoors in a grow tent. Indoors will allow you to grow throughout the year as you can control temperature and lighting. The choice of strain will also affect the growing cycle but indoors you can generally reckon that for most strains a two to four-month cycle is the norm.