What substrate for water lilies?

[sns26]

This is for my outdoor pond. I plant the lilies in smallish plastic tubs; the guys at lilypons gave me a bag of thick clay that I used for my first planting a few years ago but I'm way overdue for a divide-and-replant. I've seen the API pond media but it just looks like Turface...which is to say inert.

[Tim_Koles]

Inert is just fine. Water Lilies are heavy feeders and do best with tabs or granules mixed into clay. I have a pile of soil in the yard I go to but bagged clay products work well. Just don't go for potting soil or top soil. To many organics and stuff that will float. I imagine that Sean's mineralized soil would work well too. I get the pelletized ferts from Pondmegastore.com. These guys are associated with them and have a couple of good videos that I found helpful.

https://www.youtube.com/watch?v=GC8PaZCFLSg

[Linus_Cello]

Some folks use kitty litter.
I say use soil from your yard and sieve out large organic matter like sticks and leaves.

[sns26]

Some folks use kitty litter.

Interesting. The Lilypons guys just gave me clay--the same clay that lines their ponds. Because it's silty and messy if you disturb it, they told me to cap the pots with pea gravel. It has worked fine for the last couple of years but I'd love to be able to switch to a less messy media in return for regular tablet-style fertilization.