Sudden Red Petioles in Flowering: The Root Cause?

I'm trying to get to the bottom of this issue which suddenly popped up; red petioles (leaf stems) appearing as soon as flowering started. I see much of the "conventional" wisdom suggests this is a genetic trait, however I'm not so sure about that. (in my case/my plants anyway)

As soon as my plants began to bud, I applied molasses and a high(er) phosphorus fertilizer. In addition the weather cooled down a bit. Rain happened. (my plants are outdoors, in soil)

One of those things seems to be the cause of the reddening petioles. They were completely green and 'normal' before any of that occurred. I'm thinking the real issue may be "elemental antagonism" (AKA "lockout"?) as opposed to genetic traits or temperature related physiology.

Another thing I'm noticing this year is that the buds haven't gotten that burst of growth they usually do. (where you can see obvious growth each day for a week or two)

I want to take an informal poll:

Did your plants suddenly develop red petioles as soon as you applied molasses and/or high(er) P fertilizer AKA "bloom builder", "bloom booster" etc?

Did your plants develop red petioles suddenly even if you did NOT use higher Phosphorus fertilizer and /or molasses?

I've also seen suggestion that use of molasses raises PH. Is there anyone who can confirm that?

And also, looking for any corrective measures which can now be taken to relieve the red petioles and/or slower bud growth, given that the season is near end. I have around 6 weeks or less frost free season to go.

Plenty of views and no comments?

Anyway, I'm reviewing video from past seasons. This (below) is 09-16 a couple years ago, when the nutrient strategy was simply to use a good soil mix in a prepared hole. I used storebought potting soil, manure and sand same as this year. Same spot too, different hole location within the small area. I also used songbird poop as a top dressing, and during veg it need epsom salts. No chemicals or commercial fertilizers were used, neither was molasses. There was hardly a hint of redness on the petioles, and the buds were larger +/- one week prior to the same date this year. same seed strain too BTW.

I'm open to any explanations or advice. But I'd also like to see if collectively we can draw any cause and effect relationships to red petioles and the use of molasses, and/or high P fertilizers etc. along with figuring out what threw this season out of whack.

Here are comparative photos of the exact same growing shoot/bud from this year, dates noted. The earlier one was when I first noticed clumps of pistils this year. You can see the red petioles have occurred relatively quickly and the bud growth is not very impressive.

I find when temps get lower, leaf stems get red/purple.
Also phosphorus lockout can be the cause, phosphorus isn't available to the plant at temps of less than 15C, Can't remember if this is air temp or soil temp.

a cold snap will indeed do it................