The Blackberry Tales 6 - X marks the spot

My garden is a constant source of amazement and wonder to me.  Not only does it contain the things I have planted and planned but then there are the inexplicable things that happen/grow and I know point to a more mystical/fantastical world that I can only imagine that is happening.

In the wild garden there are the patches of lime green grass.  Just a few tufts, but there they are, distinct and proud.
What do they mean?  They must signify something?

Does it point to where the gold seams are?
Are diamonds found underneath these areas?

Do they mark the ancient burial tombs of the little people?
 Who knows?  The less enlightened mutter things about self-seeded grasses from other parts of the garden, but seriously, how likely is that?