How many hours a day should grow lights be on? 420 Guide for You

Lighting is one of, if not the most essential ingredient needed for a quick, highyielding crop. Your lights may very well be your single greatest expense, but very well worth the investment. Maximizing light distribution to your plants will enhance photosynthesis tremendously. Photosynthesis is the process by which carbon dioxide and water are turned into sugary plant food and oxygen. In effect, the more light your plants receive, the faster and bigger they will grow.

Indoor growers are always looking for ways to increase the health, growth, and output of crops. One method many growers use to accomplish this is to allow grow lights to stay on 24 hours a day. But is that the best option for your plants?

It is not recommended to leave your grow light running for 24 hours straight. Twenty four hours of light can prevent a plant from effectively carrying out the respiration process.

If your plant is not responding to 12 or 18 hours of light, you may need a stronger grow light or you may need to feed your plant nutrients. Also consider whether you need to adjust your cannabis grow lights hang height.

The ideal amount of light exposure for fruit or vegetable bearing plants, including cannabis, is between 20 and 40 moles of light per day.

During an 18 hour vegetative phase light cycle, you can produce 20 moles of light by using an LED grow light with a PPFD value of 308 micromoles (umol) of light.

To produce 20 moles of light during flowering phase, you’ll need a higher PPFD value of 462 umol from your grow light due to the shortened 12 hour lighting cycle.

If you want to maximize yield you’ll need to produce 40 moles of light per day for your plants.

To deliver 40 moles of light during vegetation, that’ll require using a full spectrum LED grow light with a minimum PPFD value of 617 umols for 18 hours.

To deliver 40 moles of light during flowering phase, your grow light will need a 926 umols PPFD value to compensate for the shorter 12 hour light cycle.

Marijuana plants need plenty of light and very little darkness until they reach the flowering stage. The following chart explains the amount of light that you should provide for the various growth stages:

• Seed germination – 18 hours of light for 5 to 10 days

• Seedlings – 18 hours of light for 2 to 3 weeks

• Vegetative stage – 18 hours of light for 3 to 16 weeks

• Flowering stage – 12 hours of light for 8 to 11 weeks

When you’re growing weed indoors, you have to manipulate the light to help the plants reach their full potential. You can use lighting to mimic the natural change of the seasons. However, you can also adapt the lighting to encourage the weed light cycle to move more quickly. For example, adding more hours of darkness will force the plants to flower sooner than they might have otherwise.

No matter what, you will need to change the marijuana lighting cycles if you want to encourage the plant to flower at all. Switching to a 12/12 schedule will cause the flowering cycle to begin.

You can also jump-start the flowering stage by giving your plants 36 hours of consistent darkness. This reduces the levels of phytochrome far-red significantly. Your plants will begin the flowering process, and you can switch to a 12/12 schedule after the 36 hours.

It’s essential that the periods of darkness are uninterrupted. If you open a door and allow light into the room for a second, you’ll alter the plants’ growth. You can ensure constant darkness by making sure that no light leaks into the grow room.

To do this, turn off all of the lights, and enter the room. Allow your eyes to adjust to the darkness. This may take up to 30 minutes. Then, hold your hand in front of your face. If you can see it, light is entering from somewhere.

If you need a best recommend, this one will help you.

 MARS HYDRO TS 3000W LED Grow Light    

ENHANCE LIGHT REFLECTION

Reflective aluminum hood helps to improve the light efficiency, scientifically engineered to keep the balance of PAR output and coverage area. Extremely bright, ideal for all kinds of indoor plants at all growth stages especially veg and flower.

SILENT INDOOR GROWING

Innovative fanless design and no need to worry about heat dissipation. Liberates you and your plants from noise whether in sleep or activity time. Helps your plants become healthy and thrived in such a quiet environment and you can enjoy the bumper harvest!

FREELY ADJUST BRIGHTNESS

With dimmable feature, the light can be started with low power and gradually increase. Just remove the silicone plug on the top and adjust dimming with a precision flat head screwdriver. It can be used to program VEG and BLOOM brightness individually.

It’s vital that your cannabis plants get plenty of sunlight while they’re in the vegetative state. If you want them to flower, you must provide them with 12 hours of uninterrupted darkness each day.

Growing indoors typically produces the most stable lighting conditions. However, you might have more space and flexibility if you grow outdoors. Taking advantage of natural sunlight can also save you money and energy. If you grow outdoors, make sure that you pay attention to the marijuana lighting cycles so that you can maximize your yield. Choosing best led grow lights is important, hope you have a best choice.