New Grower When to harvest autos? Your leaves will tell you.

One of the most frequently asked questions is how do I know when my autos are ready to pick? The convention wisdom from growing photo period plants was to watch for color change in the trichomes, or crystals. For an uplifting high, harvest when the trichomes are all cloudy, for more of a stone, wait till a percentage have turned amber. Sound advice, for photos. But autos are a little different. While some strains have shown amber trics, many do not.

So how do I know when they are ready? I watch the the fan leaves. Over the past several years of growing autos I started taking samples at various stages of growth to evaluate the high. I tend to prefer my smoke with a little stone so began to leave them longer than the 8-9 weeks that are advertised. I find that around 11-12 weeks the plants are ripe for me. I also began to see a correlation between the color of the fan leaves, the color of the trics and the high/stone quality of the smoke at the various sample intervals. It seemed that the greener the fan leaves, the more clear trics the buds had. As the fan leaves started to yellow and die off, the trics became less clear and more milky. By the time that all the fan leaves had died off and the bud leaves were starting to yellow, I got the quality of smoke I wanted. At that time most of the trics were now milky with no, or only a few, clear ones. Here are some examples:

AA 2.JPGAA 011.JPGOnyx and AA 014.jpgAA 1.JPG

I've found this to be a very reliable method. It takes about 3 weeks for the fan leaves to die off. During that time the buds will continue to fatten up as the plant uses the energy stored in the fan leaves. So when I see my leaves start to yellow, I wait a week, then begin cleansing them. Two weeks later they will be well cleansed and read to harvest.

Of course there will be other factors such as genetics, lighting, nutrients, pot size, etc. that will effect how long a plant takes. But as a general guide for when to pick, just watch your leaves.

NOTE: If you have questions regarding your personal grow, please post them in the appropriate forum and not in this thread.
 
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When fan leaves start to go yellow still continue with ferts and gradually reduce. ... and when bud leaves start to yellow then we're one week out from harvest and water with just plain ph water and blackstrap molassas?

I hope muddy weighs in on this. From what I read, the first post said: "It takes about 3 weeks for the fan leaves to die off. During that time the buds will continue to fatten up as the plant uses the energy stored in the fan leaves. So when I see my leaves start to yellow, I wait a week, then begin cleansing them. Two weeks later they will be well cleansed and ready to harvest."

So, IMO you're off by a week. It doesn't say to cut back nutes. Just to wait a week from when fan leaves start to yellow, then water only for 2 weeks. That fits into his lifecycle post which says weeks 10 & 11 should be pure water.

You mentioned molasses. I'd like to know if that's ok during the "water only" period. I'd also like to know if a flush additive would be useful in the last 3-4 days. Like Clearex or FloraKleen? It seems like that's standard practice for photosensitives. I wonder if it's useful for autos.
 
Tomorrow, Tuesday will be Week 8, Day 1. I was going to continue with the nutes for 1 more week then start cleansing with plain PH water for a week or 2 until all big fan leaves go yellow or brown.

I'm using the Autopot like Duggy and Hazy so I'm feeding bottom up. I'll refresh the rez with plain PH water for the last 2 weeks or perhaps water top down with PH water and blackstrap. I did a one liter top down feeding PH water with a teaspoon of blackstrap yesterday hoping to sweeten things up or fatten up buds in the last phase of life.

I looked up flushing and Ed Rosenthal says flushing is detrimental before harvesting so I decided not to flush with a large volume of water but only regular feeding with 20% runoff.

OH BTW: I'm growing in coco so should I still be using nutes or for the last 2-3 weeks there will be no nutrients at all. What's the harvesting process for coco growers?
 
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I looked up flushing and Ed Rosenthal says flushing is detrimental before harvesting so I decided not to flush with a large volume of water but only regular feeding with 20% runoff.
Please correct me if im wrong but flushing for harvest and flushing for cause of deficiency is two different things, when you flush for harvest you just water it like always but with plain water or with molasses(?)
and if you are flushing to get rid of deficiency you will be flushing with more water to cleanse the roots and grow medium.
 
Please correct me if im wrong but flushing for harvest and flushing for cause of deficiency is two different things, when you flush for harvest you just water it like always but with plain water or with molasses(?)
and if you are flushing to get rid of deficiency you will be flushing with more water to cleanse the roots and grow medium.

Yes, I believe you have the right of it. As always the devil is in the details....
 
Took these fan leaves off today. Too soon? Also, does these top cola leaves still look green or are they yellowing? They look yellow me under the led, maybe its the color getting was washed out to me.

I think I'm 2 weeks out now, 10 weeks looks to be the right time.
 

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Yes, I believe you have the right of it. As always the devil is in the details....

Yea, I was referring to a couple videos on youtube where they showed flushing before harvest with large volumes of water, then I googled it more and found the ed rosenthal article on his website. Also found a good article about not putting molassas in your res tank, lol.
 
Took these fan leaves off today. Too soon? Also, does these top cola leaves still look green or are they yellowing? They look yellow me under the led, maybe its the color getting was washed out to me.

I think I'm 2 weeks out now, 10 weeks looks to be the right time.

My rule of thumb is to give the girls a good 8 weeks of flowering. If you veg for 4 weeks then the girls should be ready in 12 weeks. Now this just my way of calculating when they will be ready. I've had Short Riders take 13-14 weeks, when Nirvana says they would be ready in 8 weeks.
 
Please correct me if im wrong but flushing for harvest and flushing for cause of deficiency is two different things, when you flush for harvest you just water it like always but with plain water or with molasses(?)
and if you are flushing to get rid of deficiency you will be flushing with more water to cleanse the roots and grow medium.

Correct. It does get confusing, so we've been referring to the plain water at the end as a cleansing, rather than a flush.

https://www.autoflower.org/f2/flushing-vs-flushing-12578.html
 
60 Day Wonder - DNA Genetics. It really is ready in 60 days. I could chop down now and it still be great smoke. Gonna maximize her potential and let it go a couple more weeks. Still a lot of green leaves. I will post some pics to help others know the signs to look for. Took a few more yellow leaves today. The lower bud sites are opened up to more light now.
 
Leaves I'm taking next, a few more days and they will be sucked dry of nutes soon. Here some pics of yellowing leaves.
 

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