Flowering Light Cycle Interrupted – Here’s How to Deal with It

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Interrupting lighting for your plants during any stage of growth can lead to extreme changes. Plants have their circadian rhythms. As a result, they respond differently to light. 

Various aspect might interrupt your plants. For instance, children playing around the grow room might mistakenly switch the lights off or tamper with the lighting systems. Some other times, power outage or problem in your area might also disrupt the lighting. 

Other people try to manipulate cannabis plants to flower by interrupting the lighting systems. This might work momentarily. However, other times interrupting the lighting cycle for your plants could turn to be disastrous. 

When lights are interrupted, you need to fix this interruption as soon as possible. If you don’t do that, you will affect the yield of your plant. 

In this article, we will discuss with you the effects of flowering light cycle interruption and how to deal with it if it happens. 

Extra Hours of Light During Flowering Cycle

During the flowering season, cannabis plants need more hours of darkness. If the 12 hours of darkness in your grow room is interrupted with light, your plant stops flowering. Light interruption turns the flowering signal off. 

And if the light is turned on and off during the flowering season, it leads to plant stress that causes seedy and hermaphrodites buds. 

The light interruption is serious. Even a little leak of light through your grow room cracks, vents, or door frames, would cause problems. 

So at all cost avoid interrupting your dark hours. When your plant starts flowering, don’t allow children to play around your grow room. Also, make sure that your lighting system is properly installed and it doesn’t turn on itself. 

Test your room of any light interruption. To test this, you need to close yourself in the grow room. Check whether there is any light coming to your grow room through cracks, vents or any other opening. 

Once you find any opening that is allowing light, get it fixed. Close all gaps that brings light to your grow room. 

Extra Hours of Darkness in Flowering Cycle

Your plant should be in darkness for at least 12 hours a day during the flowering stage. Extra hours of darkness during this stage doesn’t hurt your yields. Leaving the plants in darkness for up to 24 hours might not cause any harm. 

However, an interruption to light that could leave your plants in darkness for many hours might hurt the plants. 

We have mentioned that the lowest hours are 12 hours and the longest darkness hours can be even 24 hours. So, when you notice a power interruption that causes darkness in your to grow room, we recommend that you don’t turn the lights on immediately. 

Let your plants stay in darkness for the 24 hours. Time and turn on the lights at the normal lighting hours. 

If for example, your plant darkness hours for your plant runs from 6.00 PM to 6.00 AM and you notice the lights are still off at 9.00 AM, don’t turn on the lights. Let the plant remain in darkness until the following day at 6.00 PM. 

Turning the lights on after an interruption of darkness, it will cause some stress to your plants. And it will affect the overall budding and flowering process. 

Normal Flowering Light Cycle

It’s important to understand the normal light cycle for plant flowering. Once you understand the normal flowering cycles, you will be able to understand know when you disrupt the normal light cycle. 

Plants in grow room needs a certain level of grow light wattage supplied in certain hours. The need for flowering light depends on the stage of the plant growth. There are stages where you should provide more hours of light. Other stages require more hours of darkness. 

The stages of plant growth can be divided majorly into four categories – transition, first buds, buds growth, and buds ripen. 

  • Transition Stage

This is a stage in which plants transits from their vegetative to flowering phases. In the transition stage, the light should be provided in a duration of between 12-14 hours. 

At this stage, the plant is still growing. So, its light needs do not differ much on the vegetative stage. This usually happens in the first 1-2 weeks during the flowering stage of a cannabis plant. 

Therefore, if the plant is not supplied with light for 12-14 hours in a day, then it means that its light cycle has been disrupted. If less light is supplied, then the plant won’t transition as required. It will flower, but you won’t get enough yield from the plant. 

  • First Buds Stage

This is the phase which you will see the first buds develop in your plant. At this stage, you will see the first flowers developing. 

Once you start seeing first buds, you should reduce the light supply. Ensure you only provide light for a maximum of 10 hrs a day. However, the minimum of the light provided should be 8 hours in a day. 

On the other hand, the grow room should be left in total darkness for 14 to 16 hours. 

First, bud stages happen in the 3rd and 4th week. By the fourth week, this stage is completed – you will start noticing real buds. 

At this phase, the growth of your plant will slow down. To give the plant a maximum yield, the number of light intensity and hours should be reduced and increase the amount of darkness. 

  • Bud Growth Stage

This is the stage that begins from the fourth week of the flowering phase. Here is where you see the real flowering of your plant. 

To ensure the buds mature as required, you need to reduce the number of light hours and increase the darkness hours. Supply light for 6 hours and darkness for 18 hours a day. 

Plants need Florigen which is a plant hormone responsible for flower growth. The hormone is only produced at night or when there is darkness. So, providing more hours of darkness will ensure that the plant can produce more Florigen. As a result, the flowers will mature and grow easily. 

  • Flower Ripen Stage

At this stage, the flower has fully matured. You don’t need to change much of the light supply. You can keep 6 hours of light and 18 hours of darkness. 

However, as the flowers mature, don’t oversupply light. It will be affecting the ripening of the flowers. Some will wither before they mature. 

However, darkness won’t affect the flowers. You can leave your plants in darkness for up to 48 hours. Excess darkness speeds the ripening stage. 

Specific Issues Caused By Light Interruptions

We have already mentioned that the interruption of a light cycle during flowering will affect the entire process. The same also happens in other stages of plant development. 

The following are specific effects that light interruption will cause in a Vegetative Stage. 

  • Plants Go Back to Vegetative Stage When Supplied with Excess Light

When you disrupt a dark cycle by supplying more light, you affect the flower development. More light will mean that less Florigen is being produced the plant. As a result, the flowers do not develop or grow. 

At the same time, much light facilitates photosynthesis. This will cause the plant to develop its leaves and continue growing. With a few days, your cannabis will re-vegetate. 

This problem is usually seen in early stages of plant development. 

Solution: If you notice that your lights were on for many hours than expected, you can reverse this issue. All you need to do is leave your plant in the darkness for many hours. This will induce the overproduction of Florigen. Your plant will, therefore, reverse the vegetative stage and start flowering again. 

Leave the plant in darkness for at least 24 hours if you had exposure to light for more than 16 hours. 

Once the 24 hours are completed, restart the normal cycle. Depending on the stage on which your plant is at, provide relevant lighting hours. 

Follow the recommendation that we have previously discussed. 

  • Buds Mature Faster

Another effect of light disruption is the maturity of the buds. It might seem like something to celebrate about; however, you shouldn’t disrupt the normal process of flowering. 

Some growers make the mistake of letting the plant remain in darkness for it to flower. When this is done, the flowers mature quickly but the quality of your yield is affected. 

Solution: Ensure that you maintain a balance between the light and darkness hours. Nothing should be overdone. 

  • Gender Changes

When the light operation of your grow room is disrupted, things get out of control. If lights are turning on and off regularly, it confuses the plant. As a result, your cannabis develops scrawny buds that eventually turn to be hermaphrodites. 

The sudden change in the light it disrupts the plant from growing as male or female. The light intensity is also another cause of this stress. When your plant experience overheating or thermal stress, it develops side effects of hermaphrodites. 

Solution: Get a lighting system with correct light intensity and wattage for your plants. Also, ensure you avoid turning on and off lights in your grow room. 

Best Lighting System that Won’t Interrupt the Flowering Light Cycle

The first step in ensuring that your plant flowering light cycle won’t be interrupted is ensuring that you get a perfect lighting system for your to grow room. 

In the market, you will find lightings of all kinds. However, not each growing light you will find in the market is perfect for your plant. In this case, we recommend that you get the best lighting that will give your plant a maximum yield. 

There are two types of grow lights that will give you better performance. These are LED grow lights and HID grow lights. 

LED Grow Lights

LED grow lights come in two different types – T5 and CFL. T5 are meant for large grow tents. For a small tent, we recommend you to buy a CFL. 

With all conditions taken care of, you can expect to grow 0.25 grams of buds under every What. So, it means if you use 1000W yield, you would 0.5 lbs. And this isn’t a good yield to get from your tent. 

High-Intensity Discharge (HID) Light

HID give better yield as compared to the fluorescent lights. They come in three types – Metal Halide (MH), High-Pressure Sodium (HPS) and Ceramic Metal Halide (CMH). 

However, to get the best out of these lights, you need to boost them with hoods or reflectors. 

But one of the problems that you will have to deal with is heat. Once you have installed the lights, you need to employ cooling techniques for your tent. Otherwise, your plants will be destroyed, and they won’t produce as much as you would wish. 

Click here to learn How to Cool a Grow Tent: Most Exclusive Cooling Solutions EVER.

Once you have cooled your grow tent, you will get the maximum yield with this light. 

With a well set up HD light, you can get 1 gram of buds forever watt. In the space of a small space, you would make a total yield of about 2.5 lbs. 

However, to achieve this, you need to manage your light as your plants grow. Use MH lamps at vegetative stages, and when your plant starts flowering, put the HPS lights. This strategy would maximize the total yield you will get from your 4×4 grow tent. 

This is a light that will keep light of your room. It doesn’t overheat and its energy-efficient. With it, you will have everything you need all year round. 

Parting Shot

Light and darkness are essential in the flowering cycle of cannabis. Both need to be supplied in the right intensity and duration. If that’s not done, the effects are adverse and you won’t get the yields you desire to have. 

Follow the light cycle recommendation we have discussed in this article. Your plants will flower and produce maximum yields. 

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