Darkening veins on gerberas

Hello!
I'm hoping someone out there can help me with this "problem" I'm having. Should I panic if I see this happening to my gerberas? The veins of the leaves are starting to purple! Have a look....



The plant shares a self-watering container with 2 other gerberas. The other two are OK, no such symptoms.
The soil is consistently moist -- so is this a symptom of root rot or something??
So far they've been very happy (been flowering and leaves are turgid), but this symptom seems to be spreading to other leaves.
Pls help...

Thanks a lot!!!
David.

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David

I haven't grown gerberas myself but those leaves look quite healthy apart from the dark veining. Could it be that plant is a different variety from the other two and the dark veining is normal as the plant matures? I've seen something similar with some nicotianas.

Alternatively, it might be a deficiency of some kind but the rest of the plant looks so robust.

Just keep a close watch on them, I think.

 

Thanks Flinty and Marley for your advice. At least I'm not overly worried for now.
Will keep a close eye on it, and give it a bit more phosphorus to see if it's a deficiency issue.
As for whether it's a particular strain of gerbera, I have no idea -- but the color of the blooms are maroon.

 

Those blooms are spectacular - I can see why you grow them.

 

Yes, I fully agree. They are a real joy! Especially when you see them growing and growing.
This is a before and after shot of a red gerbera over 2 months.



Another photo to share -- this pink one is planted together with the maroon (and veined) one. hehe...



And an orange just about to bloom -- the beginnings of new life. Also, notice the jagged edges of the petals... Wonderful, isn't it?



Hope they've brightened up your day!