wtf is this??

A friend of mine has 3 plants outside. Just started flowering last week. Two are the same strain. The two that are the same have purple or black colouring to the bud sites. We took a bud off and looked at it under a scope and see no bugs and to me it doesn't look like mould either. I have the same plants in my garden and they are fine. Here are a couple of pictures. Any help here would be appreciated.

What is the strain?

I don't know. Smells lemony or grapefruity. I got it last year and have been growing it ever since by cloning. I have one of the same in my yard and have grown many over the past year and none have done this. Could it be nutrients he's using? Here's a pic of my plant same strain outside as well.

Nobody has any input here??

The only thing that would discolor buds is mold or bud rot. If it doesn't smell bad (like rotting) than its probably just a strain thing. Some strains turn purple. Also when I started growing I had a few plants I overfed with too much nutrients. sometimes the stems would go purple.

Yeh looks like he has a problem with his medium/feeding....

I've seen outdoor plants discolour like that in extreme cold temperatures, but it appears you are in the same geographical area, so one would almost have to rule that out.

Like others have said... investigate the medium and nutrients.

-spek

Well we are letting them continue on as is. Why not right. We just moved the one plant that is showing no signs of this away from these two. The one plant is a different strain. We shall see what happens I guess. We are only really about a week and a half into flower here. No smell to them at all. I clipped off a bud and picked in apart looking under a scope at it and it simply looks like they are purple or back. Very odd. Given I have the same strain on my deck and she's a bear!! Green buds. But we are using different soils and nutrients.