How do I flower a marijuana plant?

Question: I need help. I have a marijuana plant growing in my closet under a small 100W LED grow light. It’s a little over a month old and looks good, but now I want it to flower and make buds. What do I need?

Answer: Change the lights to only be on for 12 hours a day, with 12 hours of total, uninterrupted darkness when the lights are off. This is done by using a wall timer. That’s it! Happy growing!

-Sirius Fourside

 


 

Summary: How to get cannabis to make buds (also known as flowering, because the buds are female flowers)

  1. 12/12 light schedule – Give cannabis plants 12 hours of light a day and 12 hours of dark per day to get them to start flowering (growing buds). Do this by plugging your grow lights into a wall timer.
  2. No light leaks – Don’t let plants get any light during their dark period. This also means you should not check on flowering cannabis plants during lights-off time. Even a little light at night can cause plants to herm (make seedy buds) or revert back to the vegetative stage (known as re-vegging)
  3. Look out for male plants – If plant grow pollen sacs instead of buds, toss them immediately because you can’t smoke pollen sacs. Plus they release pollen that makes your buds seedy. Why do I not want male plants?

Want to start growing cannabis?

1.) Put cannabis grow lights on a timer so plants get light for only 12 hours a day. The long nights make a cannabis plant “think” winter is coming, and it starts making flowers so they’ll be ready before it gets cold. Note: Auto-flowering strains automatically start making buds and most strains are ready to harvest in 2-3 months from seed. That means an autoflowering grower doesn’t need to worry about light leaks or light schedules. Learn more about auto-flowering cannabis.

In order to get a cannabis plant to enter the flowering stage and start making buds, a grower needs to use a timer to put the grow lights on a 12/12 light schedule (12 hours light, 12 hours darkness)

2.) No light leaks. Even small amounts of light can cause plants to turn into a hermaphrodite, which means to grow pollen and get seedy buds. Light leaks can also make the plant revert back to the vegetative stage, which causes the buds to die and leaves start growing with rounded edges.

Look out for these symptoms that are caused by light leaks.

Light leaks cause “hermies” (an affectionate name for hermaphrodite cannabis plants). These cause seedy buds if you ignore them.

Male plants, hermies and bananas are not good. The first sign is "bananas" or "balls" where buds should be

Light during the dark period causes cannabis plants to revert back to the vegetative stage. This is the first sign of re-vegging: round leaves.

A plant that is accidentally re-vegged (reverted back to the vegetative stage) will typically display symptoms like single-point leaves and smooth edges, as well as sometimes twisted growth

3.) Remove male plants – Once you initiate a 12/12 light schedule, plant should start making buds in 2-3 weeks. Watch to make sure all plants are growing buds. If plant grow pollen sacs, that means this is a male plant, and the plants need to be removed immediately from the grow room. These plants release excessive amounts of pollen that make your buds grow seeds. A few seeds are okay, but if you have a lot it can hurt yields and also reduce the potency of buds. Learn more about male vs female cannabis plants.

After starting 12/12, plants should make buds in 2-3 weeks. If they grow pollen sacs like this, toss the plant immediately! See more pictures of male plants.

Identify male cannabis plants by their balls (male pollen sacs) which grow at the "V" where the stems meet the "trunk"

 

Learn when to harvest your buds

If you follow these steps, you’ll soon be rewarded with gorgeous cannabis buds.

I love Platinum Cookies. Check out my review of this strain!

 

 


 

Jump to…

Cannabis Light Schedules: What You Need to Know

How long does it take to grow a cannabis plant from beginning to end?

Cannabis Growing: The Basics

Where do I get seeds?

 


 

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