Replanting Our Horsetail Tub
Placing a potted pond plant in the midst of our patio is a 'mind trick' - it makes it seem more natural that there really is a pond occuring in our backyard....
folks don't consider it human made....

This is the 3rd time in 17 years that our horsetail has become too crowded in its tub.
Twice it escaped the pot, but this time it just got so crowded that it looked ugly.
First we 'peeled back' the flagstone with the curves that surround the pot....they seem to make it look as if it 'erupted' from the pond!!
Then we needed to dig the root-bound horsetail masss out.
We used a saw to cut off about 1/5 of it, which will become the new plant. You can see how the root mass has taken the shape of the rubber tub.

We added a couple of inches of clay soil (never use potting soil, it is too light-weight and will float), and added the retained pieces of horsetail. We used a few rocks to hold the pieces upright and in place. Then we began adding water. At first the water is very muddy/milky, but within 24 hours it had settled.

Below shows how we have replaced the pieces of flagstone and already the water is clearing.

This image shows the 'throw away' root mass.

Here is a link to a 'finished' picture from 2013.