New Grower The life cycle of auto flowering cannabis.

Another common question I see is when to switch autos from veg to bloom. Many people are under the impression that as soon as they see the first flowers it's time to switch. 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 time line.

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.

For more detailed information on when to harvest your plants, please see: https://www.autoflower.org/f44/when-harvest-autos-your-leaves-will-tell-you-4889.html.

NOTE: This is an informational thread. Do not post specific questions about your grow here. Please start a new thread in the appropriate forum.
 
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I did read through this thread, but decided to cut the nitrogen out when my first auto plant hit preflower. Now she looks like she's nearing completion at around day 55! I'll be sure to extend vertical growth as long as possible with my other auto girls. Thanks Muddy, great advice!
 
Hi Muddy!

I have 2 Skunk #1 Autos outdoor in week 4. I want them to get as big as possible, since we've been having shitty weather in Romania for the last 3-4 weeks.I have Biobizz Bio-grow, which is supposed to be a grow fertilizer, but has a npk of 4 -3 - 6. Is this fertilizer ok to use during weeks 4-6 or will it slow down vertical growth? Thank you!
 
That should be fine.

Hi Muddy!

I have 2 Skunk #1 Autos outdoor in week 4. I want them to get as big as possible, since we've been having shitty weather in Romania for the last 3-4 weeks.I have Biobizz Bio-grow, which is supposed to be a grow fertilizer, but has a npk of 4 -3 - 6. Is this fertilizer ok to use during weeks 4-6 or will it slow down vertical growth? Thank you!
 
what means 'vertical growth stops'? (for flowering mode)
ive seen that my plant cut on half her growth from 2 sm daily to 1sm. is 'vertical growth stops' means that or i should wait till she really stops growing at all. its a bit odd coz she's in week 7 now.
by now she flowers, but flowers are weak, not really growing in width but rather her pistils are getting more height.
what you think? is it the time to make change in feeding regime?
 
It means exactly what it says, when the plant stops it's fast vertical growth, usually sometime during week 5-6. It doesn't just stop overnight, but starts to slow, then stops. Often during weeks 4 -6 the plants can grow an inch or more a day. During this time there will be small buds, or pre flowers, as they are called. Those buds won't really start to fill in as long as the plant is still growing vertically. Once that vertical growth slows and stops the energy is transferred to the buds. At week 7 I would expect the vertical growth has stopped and it's time to make the switch to bloom nutrients.

what means 'vertical growth stops'? (for flowering mode)
ive seen that my plant cut on half her growth from 2 sm daily to 1sm. is 'vertical growth stops' means that or i should wait till she really stops growing at all. its a bit odd coz she's in week 7 now.
by now she flowers, but flowers are weak, not really growing in width but rather her pistils are getting more height.
what you think? is it the time to make change in feeding regime?
 
This tread seems more true then what seedbank sais thumbs upp and gj
 
I read this sentence, about an auto, on a website that sells seeds. "Feminized Little Dwarf is ready to harvest in 2 months regardless how much light she gets."

Now... to me this sentence tells me that I dont need any kind of special light, just let it be whereever?

*EDIT*

Oh! One more thing! Is it possible to take clones, cuttings, whatever, from an autoflowering strain, without disturbing the plants growth?
 
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I read this sentence, about an auto, on a website that sells seeds. "Feminized Little Dwarf is ready to harvest in 2 months regardless how much light she gets."

Now... to me this sentence tells me that I dont need any kind of special light, just let it be whereever?

They are referring to the amount of light per day, 24, 20, 18, etc. the plant is getting, not the type of grow light being used.



Oh! One more thing! Is it possible to take clones, cuttings, whatever, from an autoflowering strain, without disturbing the plants growth?
No. Autoflowering is genetically controlled so any clones or cuttings will be the same age as the donor plant. Plus the donor plant will take a week or more to recover and it's finishing time will be delayed.
 

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