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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Wow thanks Muddy! I was wondering how to go about the nutrient schedule since I'm new to autos, and this really helped me out. I planned on making the switch to flowering nutrients during preflowering so you have saved me some trouble. I'm debating giving one of my plants flowering nutes during preflower and the other one not, in order to compare results, but the two I have are already significantly different from one another so I don't think I could achieve anything conclusive. Thanks again for the awesome info!
 
I'm new to Auto's & here's my question, my friend has grown from the same seeds & his plants show sex already, mine are still an unknown. He grows in coco & I do in soil. Is that the reason this is happening? Both have 300 LEDs, have temps of around 78f & the same genetics, White widow x Diesel ryder. Starting to panic :D
 
I'm new to Auto's & here's my question, my friend has grown from the same seeds & his plants show sex already, mine are still an unknown. He grows in coco & I do in soil. Is that the reason this is happening? Both have 300 LEDs, have temps of around 78f & the same genetics, White widow x Diesel ryder. Starting to panic :D

Different types of genetics begin to show their ladie parts at different times but patience Is the key


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No two plants are the same, even clones can vary. Just like children learning to walk, some do it early and some later. with autos, depending on strain, they'll flower at 20-40 days, and I've had strains at both ends of that range.

I'm new to Auto's & here's my question, my friend has grown from the same seeds & his plants show sex already, mine are still an unknown. He grows in coco & I do in soil. Is that the reason this is happening? Both have 300 LEDs, have temps of around 78f & the same genetics, White widow x Diesel ryder. Starting to panic :D
 
This thread is amazing. It helped me to clear so many doubts I had about the growth cycle.

I have one doubt though. It has been established that the switch from veg nutes to flower nutes should be done around week 5/6 when the vertical growth slows down, but what about a flower stimulant like Delta 9? Should I wait for week 5/6 as well or it has to be used earlier?

best regards and have a great growing year!
 
I would stay with the same , switch when vertical growth has all but stopped..... don't confuse pre flower with flowering?
 
Correct u will see preflowers on autos shortly after she had shown sex.this is not the beginning of flower.alot more growth to come.stretch will follow and when stretch is over then bud mode begins.u need to keep feeding ur auto on veg feed until stretch is over .as the plant will need the nitrogen in the veg feed to finish veg growth is over.when u see stretch is over then switch to bloom;) happy growing
 
hey beast! not to hijack this thread but I'm in my own rut. my plants are at day 43 and still about 12in. messed up and under fed at the beg. n.l autos . I'm still feeding early bloom. should i be starting late bloom nutes next feeding? trying to get them to grow more but maybe i should try to build buds. they're pitifully small. they're already getting sticky too. lst ed them so i have 8-12 buds per plant.
 

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