Nitrogen depletion late flowering

[DocGee]

Thanks for the thoughtful reply, Muddy, and especially that second link was very helpful. I was starting to suspect that my trichs would never go amber with my last harvest of autoflowers. Very few did, and those plants were pretty used-up looking by the time I harvested. Because of the nute burn I experienced with that batch, I didn't see this natural yellowing off pattern by itself... and I know that I harvested my first grow too early, so this is the first time I'm seeing a healthy, generally well-tended plant go full cycle.

Yeah, I had a little brain fart there on the Phosphorus/red petiole thing. i've ended up doing different foliar sprays for different plants in the last couple weeks, the first of which was a dilute blooming nute (P-K) when the red petioles started bothering me. It wasn't in time for this RRF – which I still suspect just tends toward red stems due to genetics – but my photosensitive mother plant looks like she's back to green petioles. The abrupt yellowing leaves on the RRF is what got me thinking about CalMag, but I now understand she's just starting her death dance.

Thanks again for passing along the wisdom. I've been having almost as much fun learning about growing as I do enjoying the results. I said "almost."

 

[Muddy]

Very nice my friend. Looks like you're really getting the hang of growing autos, which doesn't surprise me in the least.

My Mi5's and Onyx's did just exactly as you've outlined Muddy. I stopped ferts about two weeks ago, just when the yellowing was getting started. And as you can see now, they have completely yellowed and the bulk of the leaves have been removed to the fire. On about half the plants the hairs are still clear, not having begun to get cloudy or brownish. The other half has stopped producing hairs and are definitely trying to finish. To my mind they can be cut at any time now, I enjoy them at all stages of flower. It's now 9 and 1/2 weeks from the Dec 11 seeding, and I'm a happy camper.

 

[Muddy]

You're quite welcome. You're not alone. Many people get confused and concerned when they see the leaves start to yellow. Glad I could help.

Thanks for the thoughtful reply, Muddy, and especially that second link was very helpful. I was starting to suspect that my trichs would never go amber with my last harvest of autoflowers. Very few did, and those plants were pretty used-up looking by the time I harvested. Because of the nute burn I experienced with that batch, I didn't see this natural yellowing off pattern by itself... and I know that I harvested my first grow too early, so this is the first time I'm seeing a healthy, generally well-tended plant go full cycle.

Yeah, I had a little brain fart there on the Phosphorus/red petiole thing. i've ended up doing different foliar sprays for different plants in the last couple weeks, the first of which was a dilute blooming nute (P-K) when the red petioles started bothering me. It wasn't in time for this RRF – which I still suspect just tends toward red stems due to genetics – but my photosensitive mother plant looks like she's back to green petioles. The abrupt yellowing leaves on the RRF is what got me thinking about CalMag, but I now understand she's just starting her death dance.

Thanks again for passing along the wisdom. I've been having almost as much fun learning about growing as I do enjoying the results. I said "almost."

 

[DocGee]

I decided to flush the soil in my RRF, since it seemed to be within a couple of weeks to harvest, given the yellowing leaves. The runoff was ridiculously acidic, in the 3-4 range! A lot more flushing later – with my tap water, which pushes 8 – I got it back to 6-ish. Hopefully the pH adjustment and all the chlorinated water won't cause a quickly fatal shock, but I have a decent grow in the existing buds even if it completely dies off now. (And some gorgeous, dark plump seeds.)

My other plants, all either younger or in much bigger pots, were headed the same way, though they showed no signs yet. The younger ones were developing a little slowly, albeit beautifully green, so hopefully they'll see a growth spurt in recovery. And my big photosensitive mother plant in a humongous pot – about 3 weeks into flower – had slower bud development than I was used to with autoflowers, but still ample, lush foliage. I didn't want to feed her too much chlorinated water – and her acidity was not nearly so urgent – so I'll get some real pH up solution tomorrow to add in with an aired out gallon.

And I'll surely be watering more deeply, less often, to generate runoff to test more frequently.

 

[JM]

sounds like you got a good handle on the problem mate! :thumbs: should be good... 2-3 days you should see the recovery results come on... :smokebuds:

 

[DocGee]

Quick updates...

Here's how my RRF harvest ended up, and early testing says it's very good.

https://www.opengrow.com/gallery/image/76304-rrf-carcass-after-harvest/
https://www.opengrow.com/gallery/image/76305-are-these-big-gorgeous-seeds-or-what/

A little off-topic for this forum, but my big photosensitive mother plant really appreciated the pH flush and deep watering that the issues on the RRF made me look into ... She already looked good at 3-4 weeks into flowering, but then came to life in a huge way almost overnight, piling on trichomes and now doing just spectacularly:

Bud close-up at 2/19, about 2 days after flush... https://www.opengrow.com/gallery/image/76200-21912-bud-macro-2/
Overview, 2/25... https://www.opengrow.com/gallery/image/76232-22512-wide-1/
Bud close-up at 2/25... https://www.opengrow.com/gallery/image/76240-22512-bud-macro-4/