Leaves turning purple and dying?

I am growing Afghani on my balcony in Amsterdam. Flowering started about a week ago, I have noticed that some of the initial (oldest) fan leaves are beginning to curl and are turning a purpleish color. The stems are also turning purple. I read the post below and I am not worried about the stems, as I think it is all related to the Afghani strain, but I am a bit worried about the leaves.

Is this common for the older leaves to start giving up as the plant begins to move into the last stage of life? Coincidentally, I just started to use flowering fertilizer at the first sihn of white hairs, could this have anything to do with it?

The stuff I am using was bought from InterPolm and it is called Bio-Bloei. The chemical make up is (sorry this is Dutch);

2% Stikstof (N)
6% Fosfor (P)
3.5% Kalium (K)

I am watering about every 2-3 days and using 30-40 Ml to 5 liters of water. This is what was recommended by the guys at the grow shop. Does any one have any suggestions, or should I just mellow out?

Thanks!

 

Thanks Woody,

That is what I thought, but it was getting me a bit worried. The newer leaves appear to be nice and green, although they do see to be a bit lighter than the earlier ones. Will certainly keep an eye on it. I too am growing in 10 litre pots, so I think I am OK there.

About the water, I do not test the PH and I am using Amsterdam tap water. But, I always fill the bucket at least 2 days before I plan to water and let it sit. The way I understand it, that is plenty of time for the chlorine and chemicals to evaporate. The Bio-Bloei came highly recommended as it is 100% natural, and based on what they have growing in the back room at InterPolm, it appears to work very well.

Thanks again for the reply. And good luck with the PP.