Marsh Marigold (Caltha palustris)

Are these aquatic plants.They are very lovely tiny things.

Yes Camillia, it's a 'marginal' plant that thrives in damp, wet places.
My garden is on a dry, sandy soil which would not naturally suit this plant, but I've planted it with plenty of compost to retain moisture at the spot where my pond's excess water overflows.

Like this..only buttercup I have and can't get rid of is the creeping buttercup..gets everywhere!

I know what you mean, had some when I lived in Dartford. Looks great in meadows, but a right pain in the garden!