If you have folds in your liner they will use them to overwinter. Some people sink a basket of quilt batting weighted down with a rock/brick to the bottom of their ponds. I have never tried this because I'm afraid it will breed bad bacteria over the winter.

Jenny

dick, frogs wriggle down into the mulm at the bottom of a pond, if there is mulm there!? They don't really dig themselves away down into it, to become completely covered over, as they breathe through their skin while hibernating.
Depending on what type of frogs you have, depends on what method of hibernation they use. Leopard frogs will slip into folds in the liner or lie in between plant pots.
Bullfrogs and Green frogs usually like to settle into the mulm/soil.

Some people place shallow walled containers of soil at the bottom of their ponds for the frogs to settle into. The soil does not have to be deep, just and inch or so is plenty. I have placed a mat of quilt batting, weighed down by a couple of bricks and the frogs used that to winter into. Some folks don't bother to do anything at all and the frogs survive.

Of course you can put pots of soil or mats of quilt batting down there, but that is not going to guarantee that the frogs will use it.
Remember that whatever you put down there has to come out again in the spring and it will stink a bit, because of decaying plant matter and fish waste that goes into over winter. Take into consideration how your are going to pull the containers out again in the spring, should you opt to use that method. A couple of handles that you can hook onto will make it easier. The soil containers can be awkward and heavy to handle.
That's why I use the batting, I just hook onto it and pull it out. There is a bit of a mess as the mulm and junk falls off the batting and clouds the water as I lift it out, but it soon clears up.

"Horton"

Sorry Jenny, I just about stepped on you there! LOL
"Horton"

No problem Horton. Love to hear what people do to help their frogs overwinter. I don't use anything in my pond and the frogs seem to do alright. But, then again, I don't clean my settlement pond out in the fall so that may help them to overwinter. I was worried none of my green frogs appeared this spring and didn't think any of them made it. However, I did find seven green frog tadpoles who made it. To my surprise I even had a leopard frog survive the winter. Guess they were late coming out of hibernation with the brutal winter we had.

Jenny

I use a deicer in winter, along with pots filled with soil and sometimes quilt batting. The only time I seemed to lose alot of frogs in the spring, was when I would stop and start the deicer during the winter, when I thought it occasionally warmed up. But maybe it was the fluctuation in temps, rather than just stopping the deicer.
But pots of soil and quilt batting work really well.

thanks so much, everyone!!! This is a great forum, glad I found you all

I let a small amount of fall leaves settle to the bottom of the pond. I have about 4 frogs that overwinter in the pond, and I've never had an issue with either them or the leaves.

In the spring, I just pull out the leaves along with anything else that settles in the water.

This year we have a red-eared slider. I'm not sure if she will stay out or not over the winter.