Lighting Time Required for Indoor Cannabis Cultivation

Posted on Aug 19 , 2020


In indoor cannabis cultivation, the degraded light/dark time (also called photoperiod) is very important. The first question to ask is that I am growing cannabis plants? This is because there are two types of cannabis plants: light-dependent plants and self-flowering plants. Cannabis levels that rely on light require reduced light time, while self-flowering tree species with any sun/dark time will automatically bloom after 25-30 days. Below we will explain how to set up two cannabis light/dark cycles.

Indoor cannabis glow time

How much light must I provide for light-dependent plants that grow indoors?

The light-dependent cannabis plant needs 18 hours of light and 6 hours of darkness a day during the initial stage and the entire growth stage, thereby rebuilding the bright conditions of the long and bright summer. At this stage, MH or Agro lamps can be used. After the period ends, it usually lasts 25/35 days. If you want to induce plants to bloom, you must switch to a photoperiod of 12 hours of light and 12 days of darkness to reproduce the autumn conditions. The decrease in light time will cause the plants to bloom approximately ten days after the time shift.

During the flowering period, HPS or Agro plant lights can be used. The main advantage of growing light-dependent marijuana indoors is artificial. Therefore, we can define the maximum attainable height by climbing down the timer and choose the best flowering time to switch to the flowering period. Light up for 18 to 12 hours.

How much light do indoor automatic flowering plants need

Indoor automatic flowering plants do not need to change the number of hours between the growth and flowering stages, so you need to provide the plants with 18 to 20 hours of light per day. For the automatic flowering mechanism, we recommend using standard 18-hour light and 6-hour dark light to ensure healthy plant development and adequate flowering.

For automatic flowering plants, you can also use different colors of light, MH, or AGRO for growth, HPS, or Agro for flowering.

How to keep the light time stable in indoor cultivation

In order to avoid fluctuations in the light cycle, it is absolutely necessary to use a timer analog or digital timer to turn the lights on and off. Irregular switching of lighting systems can cause serious problems for plants, such as hermaphroditism, developmental delay, and even death in some cases. Our evidence is that it is strongly recommended not to turn the lights on and off manually.


How does the light cycle behave during cannabis growth

In summer crops, because we cannot control the time of light, we are completely dependent on the cycle of natural light, which changes with the seasons. There are more and more days after the summer solstice. These days continue until the summer solstice in June. From that moment on, the days began to shorten again.

Therefore, we recommend growing cannabis in early spring, when the mild temperature rise allows the plant to germinate and grow for a few hours. Plants are usually wasted at the beginning of the flowering period in late summer, which is when they think the day begins to shorten and the night to extend.

At the same time, if we plant automatic flowering plants outdoors, we can start planting in spring, and if the latitude and climate permitting, we can even complete 3 cycles. This is because cannabis plants do not need to reduce flowering time. It is understandable that from mid-May to mid-August, the output of self-flowered hemp will reach the best effect, and the daylighting time will reach the maximum at this time.

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