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Auto Flowering Cannabis Lifecycle

Cvh

Well-known member
Supermod
Hi all,

This is guide you can follow to have a successful Auto grow.

I distilled this text from several sources and my own experience.
Hopefully it may be useful to someone.

----------------------------------------------

The life cycle of Auto Flowering Cannabis:

Another common question I see is when to switch autos from veg to bloom nutrients. Many people are under the impression that as soon as they see the first flowers it's time to switch nutrients. Perhaps a little explanation of the life cycle of autos will help to clarify this.

Weeks 1 - 3: Once you've started your seeds and they break the surface of the soil, they are in their seedling stage. The first set of leaves to appear will usually single fingered, followed by a second set that may still be single fingered or perhaps 3 fingered. Once that second set appears growth will start to accelerate as the new leaves provide more photosynthesis. This process will continue, more new leaves, faster growth. Depending on the type of soil in use, mild vegetative nutes can be introduced at week 2. By week 3 most plants will start to show their sex. Males will start to produce pollen sacks and females will display pistols.

Weeks 4 - 6: The plants are now entering a pre-flowering stage. During this time the plants should exhibit explosive growth, often as much as a new set of nodes and 1" vertical growth a day. This is the time when they will gain most of their vertical height. Many people make the mistake of switching from vegetative to flowering nutrients at this point, assuming that since they see flowers it must be the proper time. This is incorrect. If the switch to flowering nutes is made at this time the vertical growth will stop and the plant will put it's energy into producing buds. If you need to keep your plants small, or want them to finish earlier, they by all means switch nutes at this point. But if you want to get the most out of your plants continue feeding vegetative nutes until you see the vertical growth slow and stop. Depending on the strain that will usually be sometime during week 5 or 6.

Weeks 7 - 9: By now vertical growth has stopped and the switch to flowering nutrients has been made. The buds will start to fill out and put on weight, becoming hard and tight. Pistols will start to change from white to brown, orange, red, etc. By now the plants will also have developed a strong smell. Toward the end of this phase the large primary and smaller secondary fan leaves will begin to turn yellow. This is an indication that the plant is moving toward the end of it's life.

Weeks 10 - 11: At this time flowering nutes should be discontinued and only plain pHed water fed to flush the remaining nutrients from the soil and improve the taste. Yellowing of the fan leaves will continue as the plant draws the stored energy from them. Eventually they will die and fall off. By the time that the smaller leaves that come from out of the buds will also start to turn yellow. Then it's time to harvest.

I know that many of you are thinking that the seed bank said the plants will finish in 8-9 weeks, so why are you saying they take 10-11? The claims made by the seed banks are somewhat deceptive. If you switch to flowering nutes at week 3 or 4 the plants can finish in the times the seed banks say but they will remain small and not reach their full potential yield. Years of growing by myself and others has shown that autos do best if you follow this timeline.

Of course, there will always be variations depending on the strain, the environment, nutrients, etc. This information is meant to only serve as a general guideline.
 
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aridbud

automeister
ICMag Donor
Veteran
Great synopsis although numerous are finished within 9-10 weeks. Still a good bench mark on the autoflowering life cycle.

We recommend light Phos (middle amount in typical NPK feeding) every 3 waterings once sex shows....generally 17-25 days once germinated. Or organic medium with all three and micro nutrients/perlite for successful harvest.
 

Vesnican

Active member
I was exactly making that mistake described above, switching for Flower nutes too early . It makes sense to let them focus on growing until they have potential to grow, they will flower anyway. I started to seriously run outdoor autos last year, when I did 7 plants.

https://www.icmag.com/ic/showthread.php?t=330557

Other 2 years before I did just one plant 4 fun. So I am still auto noob.

@Aridbud

Can you confirm/comment that scheme to switch for Flower nutes in week 5-6?

Do you recommend training for autos? Lst? I think that Topping will slow them too much.
 

aridbud

automeister
ICMag Donor
Veteran
The optimum word here is "light feeding"...1/4 strength to start with ounce they show male/female traits.
LST, don't top, don't mess with leaves unless yellowing towards the end.
 

mona19595

New member
First auto grow Northern Lights from Nirvana seeds took almost a week to pop started 5/2. Seed cap stuck to one plant of two. Had to remove but plant seems very healthy. Both seem small to me. Not seeing explosive growth yet. They have been above ground for two weeks only. Seems longer guess I am impatient. Growing in coco and using CFLs 150 watt per plant. Still in clear solo cups that are definitely showing roots. Seems like I should transplant this week into 3 gal smart pots. Just fed calmagic to seedling's, hoping I am on the right track. Will post photo's if I get some interest in my post. Am I doing anything wrong?
 

Sorceror

Member
Is your coco pre-charged with nutrients? I always feed about 1/3 of Heads 6/9 formula general hydroponics to start the seedlings. ( I use coco bricks)

Some also recommend to plant autos directly into final pots to avoid stress during transplants.
 

aridbud

automeister
ICMag Donor
Veteran
First auto grow Northern Lights from Nirvana seeds took almost a week to pop started 5/2. Seed cap stuck to one plant of two. Had to remove but plant seems very healthy. Both seem small to me. Not seeing explosive growth yet. They have been above ground for two weeks only. Seems longer guess I am impatient. Growing in coco and using CFLs 150 watt per plant. Still in clear solo cups that are definitely showing roots. Seems like I should transplant this week into 3 gal smart pots. Just fed calmagic to seedling's, hoping I am on the right track. Will post photo's if I get some interest in my post. Am I doing anything wrong?

https://www.icmag.com/ic/forumdisplay.php?f=65577
 

RedACD

Member
That's a great guideline!

I'm a noob and still learning how to grow autos. I can already tell I messed up my timeline with the 'nutes this set. Good thing is I'll have another chance or two to try and get better this summer.
 

DjKinetics

Active member
Iv grown a couple auto's indoors most started flowering by 21-25. I'm now running some outdoors, my question is can I expect the same time scale or slightly extended for the start of flowering and the flowering period in general.
 

pumpkinpie eyes

Member
Veteran
Yeah, poster fairly timed- most of our finished in 75 days, give or take.Showing pubes about day 25.Maybe other breeders say their done in 65 days. afterthought dudes don't stretch the truth. Happy with the 5 er 6 of theirs tried.
 

Three Berries

Active member
I have some White Widow autoflowering. They are about 30" tall and about three months old. Not a sign of a flower. In the past I had no problem with Short Rider or Bubbuliscous as far as flowering.
 

Deprivation

Active member
It been shown that autoflowers can go seed to weed on only bloom nutes and thrive. Some pre flower as early as 16 days and finish in 60 so take A-trains life of an auto flower as basic generalities.
 

Kai Kai

New member
Great bit of guidance there for first time growers, also had a Tangerine Dream Auto on the go last year and was an awesome smoke.
 

NemanHarpoon

New member
Just to add to conversation. Would it be correct to say that autoflowering cannabis is more mold resistant than photoperiods,due to ruderalis gene in them?
 

aridbud

automeister
ICMag Donor
Veteran
Generally speaking, these are hardy plants. Autos tend to be bug and mildew resistant, but a few strains are more challenging than others. The ruderalis genetic tends to toughen it up a bit, which makes it ideal for first time growers.

People who are over or under feeding or struggle with some basics might want to grow autoflowers. Their fast flowering time will allow you to continue to try if your plants die out.
 

NemanHarpoon

New member
Generally speaking, these are hardy plants. Autos tend to be bug and mildew resistant, but a few strains are more challenging than others. The ruderalis genetic tends to toughen it up a bit, which makes it ideal for first time growers.

People who are over or under feeding or struggle with some basics might want to grow autoflowers. Their fast flowering time will allow you to continue to try if your plants die out.


Thank you for an answer! :)
 
It been shown that autoflowers can go seed to weed on only bloom nutes and thrive. Some pre flower as early as 16 days and finish in 60 so take A-trains life of an auto flower as basic generalities.
Yes photoperiod strains also don't mind flowering nutes all the way through. I prefer to do this as I don't particularly want overly lush, leafy plants.
 
I am growing autos for the first time under mh and hps I am wondering what's the best way to tell when you should switch your lights over is it same for lights and nutes wait till the stretch is over or slowed down?
 
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