Light Pollution and Light Leaks: How to Protect Your Cannabis Plants

Light pollution in a cannabis grow is any artificial light that reaches your plants during their dark hours, from a streetlight or a neighbor's sign to a leak in your grow tent. It can stress photoperiod plants enough to push them back into veg or turn them hermaphrodite. The fix is to find the source before it does damage: seal leaks indoors, and outdoors pick a spot clear of stray light for both veg and flower, or cover or move the plants.

What is light pollution in a cannabis grow?

Light pollution is when light from an artificial source reaches the plant during nighttime hours. If that light hits the plant directly for a long stretch, it can throw off both growth and flowering.

Your plants can get hit by light pollution indoors and outdoors. Here's what to know about both.

Light pollution in an indoor grow

Indoors, light pollution usually comes from light leaks or from a light source strong enough to mess with the plants' flowering cycle. It can also happen by accident when an electrical device — like the timer on your grow lights — malfunctions and doesn't switch the lights on or off when it should.

To figure out how to stop it, you need to track down where it's coming from, and there are several possibilities:

• A light from some electrical gadget inside the grow space.
• A grow tent that isn't light-tight and lets light in — something you can avoid by checking everything once you're done working in the space. Another possibility is that the ports at the bottom and top of the tent aren't snug around the intake and exhaust ducts. To light-proof them, seal them with tape.
• If it's a grow room, the light can come in through the window, the door or some light source inside the room.
• When you pick timers, go digital.
• If you have to go into the grow space during the dark cycle, use a green bulb, which lets you work freely without disrupting the plants' cycle.
  

To check for light pollution, on top of everything above, step inside your grow space during its dark cycle while it's daytime outside. That way you'll clearly spot any light leaks. It's also a great way to check a grow tent.

Light pollution in an outdoor grow

For outdoor plants, light pollution can come from sources that have nothing to do with your grow. They can be all kinds of things, bright enough to throw off any stage of the plants' growth.

Outdoor light pollution can come from different places:

• A streetlight.
• A lit-up sign from a shop near your patio, balcony or garden.
• Solar garden lights, which can be enough to disrupt the plants' cycle.

When that's the case, the most effective way to prevent light pollution is to check out your grow spot at night and look for any light sources around it right there and then.

How to avoid light pollution: why the photoperiod matters

Photoperiod cannabis strains rely on the light-dark cycle to decide when to switch from veg to flower. That means when daylight hours naturally shrink at the end of summer, the plants pick up on the change of season and focus their energy on building solid buds.

The catch with photoperiod strains is that the dark period really can't be interrupted. Unfortunately, light pollution from artificial sources like streetlights can be enough to cause problems in your grow. The stress can make plants revert to veg or go hermaphrodite, producing pollen and seeded buds as if they were males.

When it comes to light pollution, an ounce of prevention is worth a pound of cure, so factor it in before you plant or transplant instead of dealing with it once it's already happening. The light might come from a neighbor or the street, and in that case there's no way you can switch it off. If your plants are in the ground, you can use shade cloth to cover them at night. If they're in containers, the best fix is to move them somewhere the light can't reach them.

If you liked this, keep reading about... 

[embed]https://www.cosechalibre.com/mutaciones-en-el-cannabis/[/embed]