But, light burn can happen indoors. The leaves and even the buds begin to look white or burnt when the lights are hung too close to the plants. The heat is so high that the plants cannot tolerate it. White buds look amazing when you look at them, but it’s a sign that the buds are damaged.
Yellow leaves can also indicate light burn at times. But, do not get confused between nitrogen deficiency and light burn because they look the same. With nitrogen deficiency, though, yellowing of the leaves start from the bottom and move towards the top. Also, the leaves are limp and fall off from the plant without any effort. On the other hand, if they are suffering from light burn, the leaves feel crispy and are harder to pluck from the plant.
Prevention is far better than cure, they say. Thus, you must try to prevent light burn rather than trying to cure it. First off, light burn depends on the type of light you’re using. For instance, a CFL hung even 10 inches away from the plant will not damage the plant. The same applies to fluorescent or T5 lights because they aren’t that powerful and don’t emit a lot of heat. However, HID and LED lights positioned even 10 inches away from the plants can kill them.
Leaves turning brown and crisp is an indication of light burn too. It’s a combination of heat and too much light that fries the leaves and render them useless to the plant.
ight burn is nothing but light bleaching. You’ll notice that the leaves too close to the light turn white or look bleached. Plants growing outside cannot suffer from light burn because the sun is too far away from the earth to burn the plants. Cannabis has evolved for centuries and has adjusted to the sunlight enough to not get burnt.
Light burn or light bleaching is a serious problem if you’ve got a got a room full of cannabis plants. Light serves as food for the plants, but it can also be an issue if it goes overboard. Think of it this way – humans need food for energy, but what happens if you eat too much? Yep, you’ll have several problems from obesity to diabetes.
What is a light burn?
How to prevent light burn?
Secondly, determine the wattage of the lighting you’re using. For example, a 50W LED light may not be too harmful, but a 1000W LED will have disastrous consequences if you place it too close to the plants. HID lights are too powerful even if the wattage is low. Another problem is that they emit way too much heat that can be unbearable to the plants.
Light burn or light bleaching is a serious problem if you’ve got a got a room full of cannabis plants. Light serves as food for the plants, but it can als
Simply put, the dangers of cannabis light burn are loss of potency, a worse appearance due to burning, and loss in quality and depth of terpene profile. Of course, the biggest danger would be a significant reduction in final yield. The impact of light burn varies depending on the maturity of the plant, but this is the biggest issue for seedlings that can be easily burned by the high intensity of high-power growing lights. Next are plants in the vegetative stage which have established their ground and are self-supporting but are still susceptible to the dangers of powerful lighting. With respect to recovery, the greatest danger is for plants in the flowering stage, where it’s easy to overlook the impact of light stress as your plants change into their fall colours.
Unfortunately, if parts of your plant have experienced light burn then no amount of TLC will be able to bring them back. However, it’s possible to take remedial action by making changes to the amount of light your plant receives to a safe level and not inducing any further unnecessary stress.
If you have the resource to invest in a lux meter, it is highly recommended you do so! Not only is this useful in assessing whether your plants are getting too much light, but it can also identify areas receiving insufficient light. This is particularly important for commercial growers, as it maximizes bud production. Lux meter readings are given in lux/m 2 and should fall in the following ranges based on plant maturity:
- Vegetative: 30,000 – 70,000 lux/m 2
- Flowering: 50,000 – 90,000 lux/m 2
When something goes wrong during a grow, most growers think about water or nutrient-related issues. If you think your plants are experiencing light burn, how do you know it’s not a nutrient deficiency? Well, while the symptoms of the two can appear to be very similar, it’s possible to easily tell between the two by considering the symptoms your plants are showing. It’s unlikely you’ll experience light burn-like symptoms due to excess of any of the nutrients described below, but it’s a possibility nonetheless (particularly with phosphorus).
- Bleaching of buds
- Browning of leaves
- Leaves curling upward (“taco”-ing)
- Discoloration of leaves but veins are still green
- Irregular growth pattern
If your plants are receiving too much light and are under stress, they will exhibit some or all of the symptoms listed above. While cannabis tends to grow without issues, problems can still arise relating to watering, feeding, pH levels and so on.
- Irregular, yellow-brown spots on leaves
- Curling of lower leaves
Here are some frequently asked questions that may help you better understand light burn.
Cannabis light stress and cannabis light burn are two issues that can damage your plant and negatively affect its quality. Here’s what you need to know about this common problem, as well as how to recognize and solve it.