This doesn't seem right...

[SGD]

I noticed a few days ago that one of my plants has the pistils turning brown. I've just got around to looking up what that indicates and, according to the info on this site, I should be ready to harvest but my buds are still very small and I only switched to 12/12 about 25 days ago.
Do I harvest or leave it?

[SoOrbudgal]

Something ain't right for your time frame is what i'm seeing else your plant is too close to the light? Too warm or too close?

[SGD]

I moved the light up as far as it would go when I switched which is around 18-20 inches of space and the temp is steady between 20 22 deg C.

[Eliot Pryor]

I have an Acapulco Gold that is doing the same thing. It also isn't showing trichromes yet.

[Xena]

Not sure what info you read. You either misunderstood or it was just flat wrong. 6 to 7 weeks is the shortest flowering time I’ve seen a breeder claim and to to best of my knowledge, that’s from when they start to flower not when you switch to 12/12. Three and half weeks from switch I don’t think you’ll be chopping before Christmas......maybe not even this year.

[ChadWestport]

The plants certainly can't be near harvest at day 25, that would be a very special plant if it were. SoOrbudgal mentioned the possibility of the light being to close and that has caused the pistils to turn brown, definitely could be it.

Another thing to consider, is that they may be showing signs of pollination. When the pistil catches pollen, it turns brown and then withdraws. At day 25, it would be good to check for little hermie bananas. I've found that if a plant is going to turn herm, it's usually around week three, which you are in. Check the plant for any signs of male sacs.

[SGD]

Not sure what info you read. You either misunderstood or it was just flat wrong. 6 to 7 weeks is the shortest flowering time I’ve seen a breeder claim and to to best of my knowledge, that’s from when they start to flower not when you switch to 12/12. Three and half weeks from switch I don’t think you’ll be chopping before Christmas......maybe not even this year.

I read this https://www.growweedeasy.com/basics#when-to-harvest , scroll down a couple of pages.
I didn't make any claims about flowering times

What is the safest distance my LED light should be from the top of the plant? I have 2 plants in my tent and the other one is slightly taller and closer to the light but the pistils are still white.

[ChadWestport]

What is the safest distance my LED light should be from the top of the plant? I have 2 plants in my tent and the other one is slightly taller and closer to the light but the pistils are still white.

Safe would usually be 24". But the more specific answer will depend upon what light you are using and the intensity of it. I can get my 100w LED a lot closer than a 600w LED. The stage of growth also plays a part in light distance. Seedlings being further, flower being closer.

[SGD]

Safe would usually be 24". But the more specific answer will depend upon what light you are using and the intensity of it. I can get my 100w LED a lot closer than a 600w LED. The stage of growth also plays a part in light distance. Seedlings being further, flower being closer.

I measured the distance at 17" which is as much as the tent will allow. My light is 600W but the actual output is around 130W apparently. My other plant is still thriving in the same environment.

[ChadWestport]

I measured the distance at 17" which is as much as the tent will allow. My light is 600W but the actual output is around 130W apparently. My other plant is still thriving in the same environment.

That sounds about right. I run my 100w about 12-18" from canopy top. 12" does produce some light burn, but I only do that the last few weeks of flower. When limited on headspace, training the plants early can be a huge benefit in the end. I've had to do that plenty.