When to Start Flowering Your Cannabis Plants

The time has come to start flowering your cannabis plants. But when is the best time to do it? Let’s take a look at when to start flowering your cannabis plants.

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Flowering your cannabis plants is the process of inducing the flowers (aka buds) to form. There are many ways to do this, but in this article, we’ll focus on the most common and straightforward method: manipulating the light cycle.

Cannabis is a light-dependent plant, meaning that it needs light to grow. But it’s not just any kind of light – cannabis needs a specific ratio of light and darkness to thrive. This ratio is called the photoperiod, and it’s different for every plant.

For cannabis, the ideal photoperiod is 12 hours of light followed by 12 hours of darkness. When plants are exposed to this kind of light cycle, they will stay in what’s called the vegetative stage – a period of growth where leaves and stems expand but no flowers form.

To force your plants to flower, you need to manipulate the photoperiod so that they are exposed to more darkness than light. The most common way to do this is by switching to a 12/12 (light/dark) schedule; in other words, exposing your plants to 12 hours of complete darkness each day.

It’s important to note that you can’t just turn off all the lights and call it a day. Cannabis plants need some light even during their flowering stage, so you’ll need to provide them with an artificial source of light (like grow lights) during the dark hours.

The amount of time it takes for cannabis plants to flower will depend on several factors, including strain, age, size, and growing conditions. In general, however, it takes anywhere from 7-12 weeks for most strains to reach full maturity.

The Process of Flowering

The flowering process is started by the plant when it reaches a certain age or when the amount of light it receives per day, called the photoperiod, decreases. Nightlength, or the amount of darkness the plant receives, triggers the release of the hormone responsible for flowering, calledflorigen. Shortening the amount of light the plant receives per day causes it to produce more of the hormone, and the plant will begin flowering.

The Light Cycle

To initiate the flowering process, you will need to change your light cycle from 18-6 to 12-12. This means that your plants will be getting 12 hours of light and 12 hours of darkness each day. Many growers use adjustable timers to automatically turn their lights on and off each day.

The increased darkness signals to the plant that it is time to start flowering. The reduced light also helps prevent the formation of unwanted Males (hermaphrodites). Once you have changed your light cycle, it can take anywhere from 5-21 days for most Cannabis strains to begin flowering.

The Temperature

TheSet the temperature between 68-77°F (20-25°C) during the day, and no more than 10°F (5.5°C) cooler at night. Flowers will not mature properly if the temperature gets too high or too low for an extended period of time. If your grow room is too hot, use an air conditioner, swamp cooler, fan, or open a window to help bring the temperature down. If it’s too cold, use a space heater, close the window, or insulate your room better.

The Humidity

The amount of humidity in the air has a direct impact on how well your cannabis plants grow. The flowering stage is when your plants need the most humidity, so it’s important to make sure the air is not too dry. The ideal humidity level for flowering plants is between 40% and 50%.

If the air is too dry, your plants will start to show signs of stress, such as Leaf Curl. This is when the leaves start to curl up and turn brown at the edges. Too much humidity can also be a problem, as it can cause mold and mildew to grow on your plants.

To keep the humidity at the correct level, you can use a humidifier or a dehumidifier. You can also water your plants more frequently, as this will help to raise the humidity level in the air around them.

The Right Time to Start Flowering

The cannabis plant has a natural life cycle. It starts as a seed, then sprouts and grows into a plant. Once the plant reaches a certain age, it will start to flower. The right time to start flowering your cannabis plants depends on the strain of plant that you are growing.

The Size of the Plant

How big your cannabis plant is when you trigger the flowering stage will have a big impact on how long it takes to harvest and how much yield you get. Usually, the bigger the plant, the larger the buds and the longer it will take to flower. But there is more to it than just plant size. The number of nodes, which is where new leaves and branches grow from, also plays a role.

If you have a big, healthy plant with lots of nodes, you can expect a good yield even if it’s not particularly tall. Conversely, a tall but thin plant with few nodes is likely to produce smaller buds. So, when deciding when to start flowering your cannabis plants, take both height and width into consideration.

Another factor that affects yield is the type of cannabis strain you’re growing. Some strains are naturally conducive to large harvests, while others are less so. Do some research on the strain you’re growing to get an idea of what kind of yield you can expect.

The Age of the Plant

One common question new gardeners have is when to start flowering their cannabis plants. The answer is not as straightforward as you might think, and it depends on a few factors. Let’s take a look at what you need to consider before you decide when to switch your plants from vegetative growth to the flowering stage.

The age of the plant is one factor to consider. Younger plants may not be ready to produce flowers, and if you force them into the flowering stage too early, they may not produce good results. Most cannabis strains need to be at least 6 weeks old before they are ready to start flowering, although some may be ready sooner and some may take longer. You’ll need to consult your seed supplier or other expert growers to find out how long your specific strain takes to mature.

Another factor is the size of the plant. If your plants are small, they may not have the energy reserves needed to produce large flowers. You’ll need to wait until they have grown a bit larger before you start flowering them.

Finally, you need to consider the light cycle. Cannabis plants flower in response to changes in the length of daylight, so you’ll need to control the light cycle in order to force them into flower production. Most indoor growers use a 12-hour light/12-hour dark cycle, although some strains may respond better to longer or shorter light periods. Outdoor growers will need to wait until the days start getting shorter in autumn before they canflower their plants.

In general, it’s best to err on the side of caution and wait a bit longer rather than starting too early. This will give your plants time to mature and develop the strength they need for good flower production.

The Type of Plant

Cannabis plants can be either male or female, but only the female plants produce the flowers that are used to make marijuana. Male plants are sometimes kept by growers in order to produce seeds for future crops, but they are typically removed from the grow room once they are identified.


After weeks of vegetative growth, your cannabis plants are finally ready to start flowering. But when, exactly, should you switch them over?

The answer isn’t as simple as it might seem. In order to produce a bountiful harvest of high-quality buds, growers must consider a number of complex variables, including the strain being grown, the growing environment, and the desired harvest date.

With that said, there are a few general guidelines that can help you determine when to start flowering your cannabis plants. In this article, we’ll discuss the three most important factors to consider: daylight hours, plant size, and maturity.

Daylight Hours
One of the most important factors in determining when to start flowering is the amount of daylight your plants are receiving. Cannabis plants are photoperiodic meaning they respond to changes in the length of daylight hours (i.e., the amount of time they are exposed to light each day).

In nature, cannabis plants begin to flower in late summer/early fall as the days grow shorter and the nights get longer. This signals to the plant that winter is coming and it’s time to start producing seeds for the next generation.

For growers who want to control when their plants flower, changing the light cycle is crucial. By artificially extending the “summer” (i.e., increasing the number of hours of light per day), you can keep your plants in a vegetative state for as long as you like. Once you’re ready to start flowering, simply switch to a “winter” schedule (decreasing the number of hours of light per day) and your plants will begin to flower within a few days/weeks.

Plant Size
Another important factor to consider when determine when to start flowering is plant size. Generally speaking, larger plants tend to produce more buds than smaller plants. So, if you’re looking for a bountiful harvest, it’s typically best to wait until your plants have reached their full potential size before switching them over to a flowering schedule.

Of course, there are exceptions to this rule. If you’re growing autoflowering strains or if space is limited (e.g., you’re growing in a small closet), it might be necessary (or beneficial) to switch your plants over sooner rather than later.
In these cases, it’s best to err on the side of caution and start flowering when your plants are still relatively small. This will give them time to adjust to their new environment and produce a decent yield despite their limited size.

maturity As with any living thing, cannabis plants take timeto reach maturity — i., e., they don’t go from seedlings directly into full-blown adults overnight (unfortunately). Depending on the strain being grown , it can take anywhere from 8-16 weeks for cannabis plantsto fully mature . Obviously , this wide range makes it difficultto give a definitive answer as towhenyou shouldswitchyourplants overtoflowering . Ingeneral , though ,it ‘ s best topatientlywait until at least 8 weeks have passed before makingthe switch . This will ensurethatyourplantshave had sufficient timeto develop strongrootsystemsand robust vegetation . Floweringtoo early canresult innumerous problems , including reduced yieldsand subparquality .

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