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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quick question muddy.

how long after preflower show does vertical growth stop in average?

i know it depends on the strains -- and it says that its within 5-6 weeks (according to the life and cycle)

but lets say that the pre flower started on day 14
we would then add about 2 weeks for pre flower to flower transition = to day 28.

would be safe to start the flowering nutrients at the end of week 5? (day 35 or so) - that would be 3 weeks after the preflower
or
regardless of the number of weeks -- just wait until the vertical growth has stopped completely or slowed down?

----

i was thinking of not feeding my girls flowering nutes until the end of week 6 (day 42 or whenver the feeding is that week)

but to my surprise the girl is starting to slow down at day 29 (not sure if my eyes are playing tricks or its because shes tied down)
she is definitely drinking now tho! 5 days this time -- compare to last watering at 6 days apart.

i will see how she reacts and see if she continues to grow -- if not then id be ok switching to flowering nutes correct?

sorry for the long read muddy -- looking forward to your respond (or anyone else) thanks!
 
Sorry to be so long getting back to you, been busy with admin work.

Yes, when a plant shows sex can change the time frame. A plant that sexes at 14 days will more than likely stop it's vertical growth sooner than one that doesn't sex till 21 days. Best to just wait till you see the vertical growth slow, then stop. These are just general guidelines as it can be strain dependent. I've got some Black Skull Critical Ryders going right now that are a bigger plant than normal. They didn't show their sex till day 28, so I expect they will probably go around 7 weeks till vertical growth stops.

quick question muddy.

how long after preflower show does vertical growth stop in average?

i know it depends on the strains -- and it says that its within 5-6 weeks (according to the life and cycle)

but lets say that the pre flower started on day 14
we would then add about 2 weeks for pre flower to flower transition = to day 28.

would be safe to start the flowering nutrients at the end of week 5? (day 35 or so) - that would be 3 weeks after the preflower
or
regardless of the number of weeks -- just wait until the vertical growth has stopped completely or slowed down?

----

i was thinking of not feeding my girls flowering nutes until the end of week 6 (day 42 or whenver the feeding is that week)

but to my surprise the girl is starting to slow down at day 29 (not sure if my eyes are playing tricks or its because shes tied down)
she is definitely drinking now tho! 5 days this time -- compare to last watering at 6 days apart.

i will see how she reacts and see if she continues to grow -- if not then id be ok switching to flowering nutes correct?

sorry for the long read muddy -- looking forward to your respond (or anyone else) thanks!
 
will vertical growth stop if i switch from mh to hps but keep pumping veg nutrients?
 
will vertical growth stop if i switch from mh to hps but keep pumping veg nutrients?

Key growth organelles will recieve a greater ratio of red light, but still plenty of blue and nuetral PAR. Said organelles will also apparently recieve a greater PK ratio if you switch nutes. They will respond as well as you'd hope under the new circumstances.
 
Well Piggy you could have dished out more than one word. Lol. He's totally right though.
 

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