Put them in the compost heap or add to the soil. They have some nitrogen and will also help soil texture if you have enough of them!

Just going to say that Stera I put mine in my compost too :-)

I put the tea bags in the compost bin, but the sort my OH buys have non biodegradable bags so I have to remove them.

I'm still picking teabags out of my compost and I haven't put any on the heap for years! But I agree, used tea leaves are great.

Good around acid lovers such as camellia, rhodedendron/azalea and some hydrangeas. But use only the leaves - if you have tea bags empty the contents and dispose of the bag.

Thank you everyone.

As a child I remember my mother always emptied the teapot onto the same place on the garden. This attracted worms which she gathered for fishing trips.
Teabags were not available then. I begin to wonder why we have them now ? The tea experts say that inferior tea is put into them, the dust.
Think I will cut them open in future, and put on the garden.

I'm going to have a go, I'm saving all my used teabags.

I wonder if it makes a difference if its black tea or green - the black is fermented and the green isn't.