Someone please help!!

Hello,
I'm new to this site and need desperate help. I have ten mango plants outdoors in the ground(a little compost and humice mixed in). I've only fertilized a couple of times early on with a foliar spray. They get watered when mother earth decides to water them and they have been doing great all summer long. Now they are about three weeks into flowering. A little while before they started budding i noticed a purple like residue stating to show up on old and new growth. Now it is to the point where the purple (deep purple almost black in some spots) is starting to take over all new growth, even the white pistils are starting to turn purple. I tried scrapping it off but there's nothing to scrape off. It is the actual color of the leafs. New bud development looks slow and some leafs around the bud are a little gangley and thin. I know what some people are thinking and "no it is not a purple strain" i grew it last year and had nothing like this at all. I sprayed them with Bon-neem but it didn't do much. PLEASE!! anyone that could give advice on what I should do. I've worked way to hard this summer and don't want to have a shitty harvest because of some purple crap. Pictures will be up tomorrow.

Thanks

well sometimes when a plant is growing under stress it will start showing purple,,and also the purple could be resin(which is what i would guess) which will eventually turn into crystals,so i would leave it alone....just genitics doing its thing..

are they purple haze "mango plants"

No just regular ol mango