Each plant stage has different requirements for light. Too low light intensity will cause plants to grow slowly or even stop their development, while too strong light will burn plants and cause a variety of diseases.
When configuring the growth light, we need to use a light meter to measure the light intensity at the current location. In many northern and high-altitude areas, there will also be a problem of excessive light.
Different situations of light burning
The slightest light burning, just like this, the leaves of marijuana are like praying believers, raising their hands up high. This is because photosynthesis is maximized, and the energy produced by photosynthesis makes the meridians of cannabis leaves tight.

With a slight burn like this, the tips of the leaves began to turn white. This is because too strong photosynthesis begins to deprive ordinary cells of water, and the leaf tip is far away from the stem and lacks water supply, and the first begins to lack water and turn yellow.

When this situation became a little more serious, the edges of the leaves began to dry out and turn yellow.

For a long time, the cells on the edge of the leaf lose their activity and begin to curl.

The leaves lose their activity as a whole because of lack of water and begin to curl.

Excessive sunlight will increase water metabolism. Water shortage caused by drought in the environment, or water shortage caused by root transport function due to over-watering, excessive sunlight will intensify water shortage.

If it is because of the latter, continued watering will make the plant water shortage more serious, and even show the symptoms of root rot.

Then the plants will wilt and die in large areas.

Some light burns are difficult to see at the beginning, the color on the top will become a little lighter, and then gradually turn yellow in a few weeks. This kind of problem is not because the light intensity is too high, but too long strong light or too close irradiation distance destroys the chlorophyll in the plant cells, causing the plant to lose its green color.
The light burn that occurs during the flowering period will bleach the cannabis buds, which is difficult to see at the beginning
As the burn gets worse, the buds will become whiter and whiter, because the pigments in the buds are destroyed by light

This white bud is basically useless
In severe cases, the buds will be completely burnt, withered and yellow

The whole plant looks like it’s been burned

Slight burn will slowly destroy the leaf structure. Therefore, the old leaves at the bottom often appear to be burned first. Many growers find it difficult to associate the problem with the old leaves at the bottom with light burn. They take it for granted that this is because Nutrient deficiency or dry soil, so vigorously watered and fertilized, combined with excessive light intensity to kill the plants. This is the most dangerous horror for a marijuana plant after the seed germinates. 90% of the novices who successfully germinate kill the marijuana in this way.
The problems caused by light burning will aggravate a series of common problems such as excessive fertilization, excessive soil moisture, root rot, leaf spot disease, etc. Therefore, we must always have a light meter to determine whether the problem is caused by light burning, so as not to become more and more problematic. Suffer.
Once the plant is light-burned, adjust the environment first, give her a comfortable environment to relax for a week, and then cut all the injured leaves. The plant tissues burned by the light cannot be recovered, and it will only consume energy and waste nutrition.