Pistols turning brown at 5 week in Flower

[Dagmar]

I have three Black Jack plants who have been in flower for almost 5 weeks - Nirvana says this plant's flower stage is 9-11 weeks. The plants have been doing exceptionally well until today when I noticed that the pistols are beginning to turn brown on all the buds - both at the top of the plants and lower down (so it's not light burn). They are growing under CFLs, in Fox Farms Soil (Ocean Forest, Happy Frog, and peralite blend) and I'm using the Fox Farms Big Bloom and Tiger Bloom, along with CalMag, Black Strap Molasses, and Florilicious Plus. I defoliated about a week before flipping to flower, again a week into flower, and again three weeks into flower. I'm not a novice but I'm far from being an expert. I've been growing for over a year and completed half a dozen successful grow, but I haven't seen this before.

Has anyone seen this before? What can I do to fix/stop this from progressing?

[LuckyAcres]

I can't see much darkness on these pics dagmar but they look super healthy from here man! Halfway through their cycle I'd think they'd start turning brown about now, is it a different strain than what you've grown in the past? You looked at the trichromes with a loupe yet?

[007]

They're gorgeous! Nice grow! I wouldn't sweat it, unless they're not producing ANY new pistils at all.

[DW2]

Howdy Dagmar,
I will agree with LuckyAcres, I do not see the 'browning' that You are referring to. The plant looks healthy and good with only a little nutrient burn (the slightly brown and curling leaf tips). Can You post a closer photo showing the buds in question?

[Dagmar]

Here's a better picture. I've grown this strain before and the browning pistols didn't happen before. It's way to soon to be looking at the trichomes since it's only half way thru the flower cycle - these girls still have 5 plus weeks before harvest - the browning is not normal. Since they are in super soil, I didn't start giving them nutrients until about a week before flipping to flower and now they are only getting 1/4 of what Fox Farms recommends but still some nute burn is going on. I did some pretty serious topping and these girls have 20-30 colas each - could pushing these limits be the problem?

[Dagmar]

I'll try the flush - this hadn't previously occurred to me. Thanks

As far as bud rot, these buds are just wisps right now - doesn't bud rot occur when dense buds are too close to other dense buds and maybe poor air circulation? My buds aren't dense (yet) and the plants have good air circulation. Thanks, Tika, I'm going to read up on bud rot as I have no experience.

[LuckyAcres]

I only mentioned root rot as a back up explanation, nute burn is the most likely culprit.

[DW2]

Dagmar, the dark pistils seem to be the older (lower ones). Do You have access to a microscope? If You do, You could look closer to see if there is any unusual growth (something fuzzy) on the pistils, like a mold or fungus. On my past grows, the lower early pistils darkened first, but if this is a new thing, I do not know what it could be unless, it is a deficiency of some sort. Are You doing anything differently than the last time that You grew this strain?

[gagarin]

i have the same problem. my girl is in 6th week of flower and some of colas didn't produce enough pistils. some went brown. i flushed them because of the nute burn. i can upload pics if you want.

[Dagmar]

Have you figured out what the cause of the problem is and did the flushing help?

[Dagmar]

Have you figured out what the cause of the problem is and did the flushing help?

[gagarin]

they say its normal no need to worry. no my nute burn still slowly increasing.