sry for such a long response but i was just talking about this with someone so it was fresh on my mind and then i saw this thread...
sometimes taking a plant well into its later stages of flowering and going a couple extra days will help encourage a bit of color.
its certainly a genetic thing too tho.
ive been having alot of luck with purple lately. i have a couple strains that are pretty much purple unless they are just not in good enough conditions to do so/stressed out/heat issues, etc.
so i think that shows genetics have alot do with a plant being "very" purple. almost all plants/strains/phenos can get a bit of purple-ish color. but ive had a few that just would NOT go purple at all too. recently my last "over the summer" grow thiis past year, i had everything turning all sorts of colors except a GHS Exodus Cheese. i was suprised, it just would not turn purple at all... no matter the length of flower or temp.
PH also plays into this. there is a great article on cannabis being purple/colored and how it works etc... i believe its in Cannabis Culture magazine form back around 2005-6. they point out the old VISC strain "Fucking Incredible" which tends to need a certain PH level to show color. it tended to be fully purple and even show pink calyxes on the live plants when it would be all fancy and nice. the damn ghs exo cheese even had almost all pink hairs on the live plant. unfortunately those pink pistils will turn brown/red/orange/blue/purple... whatever they will.
a LONG time back around 2001 or so i had some bud a friend grew. it was good stuff, no idea what strain. it was nicely cured and everything, but was only about a month old from picking it or so at the most at that time. i left the bud sitting out overnight by accident, outside of any container, with normal temps and humidity etc... if anything a bit warm and dry.
the hairs(pistils, whatever u want to call them) had started to turn a very very blue heavy purple-ish color. it was mostly on the tips of the top buds. very awesome tho... i ended up showing the person who gave it to me. they let some sit out, and it did the same. ive also seen other buds that were green with purple hairs. one batch was even some "regs" or "mids" that were exceptional. just amazing bud that happened to have purple hairs instead of orange/red/brown. gave me wicked munchies!!
so in summary i feel that;
1. a plant first has to have the genetics that allow purple to happen. some will have much more than others, some none at all.
2. the plant needs to be healthy... not that sick plants dont ever have color. some look crazy!! but sometimes a plant thats very likely to finish purple normally, wont do so simply due to it having such poor growing conditions or something negative causing it stress. for instance, sometimes the bottom buds on certain plants, which typically purple easily, wont have purple on some of the buds/leaves that didnt get much light. typically the resin will be lacking in those same areas. not always tho, but just something ive noticed myself. or sometimes PH plays into it heavily.
3. sometimes purple can be from stress but its usually not an attractive purple when its from heavy stress and issues.
4. each single seed/pheno of a strain can be totally different. i grew 2 grape ape seeds from the same batch. one was ZERO green, still very nice. the other was nearly 100% purple, and is hard NOT to get to turn purple. It typically shows purple from the first signs of flowering. in this strains case, u can stress it into turning back green too by not picking it in time. looks so weird when it happens too.
ive had a number of plants turned purple that were only bagseeds from "regs" or "brick-weed" sometimes those seeds can produce nice plants!
GL getting the purple u want folks! ive seen quite a few fully purple Sour Cherry plants which are by the Breeders Boutique. they also carry a deep purple/querkle hybrid too. mostly a purple urkel strain. Ive also seen a number of purple trainwreck, bubba, la affie/la confidential, lvpk strains and hybrids all over the place. the new DNA tangie hybrids have nice pics that show some pretty colors. i want to try some of those!! the banana og/bubble gum one too! might make an order soon if i can!
happy 2014 RIU!
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