How can I save my grass from dog urine in the winter? Can I cover it ?

Try to take the dog to different areas so he doesn't overdo it in one spot. Also, you can take a pot of water to pour over the pee after he goes, to dilute it. Or put some hay or other absorbent material in that spot that can be removed after a few go-s. Just toss it around the yard and it will nourish the ground when it breaks down, or spread it on flower beds. If that's too yucky for your taste, throw it away.

I think plastic will only make for a nasty puddle if it holds the urine, and if it doesn't hold it, it's not doing any good. Maybe plastic with the hay on it?

We use sawdust it drys the urine and the feces easy to clean up safe for pets and if you call around to some farmers or loggers they will give to you free. If not still inexpensive in tractor supply or the Home Depot has saved my yard by giving my dogs this space just for this

Plastic will ruin your grass, too . I read somewhere to use something to neutralize the acid ( ammonia) in the urine , it was something you have in the house , I want to say it was milk or yogurt ??? I'm not really sure, you should look into how to neutralize urine.

Thanks for all responses they all are very helpful.

There is a product you can buy online that removes the nitrogen in the female dog's urine that burns the grass. It's called Grass Saver its all natural so it won't hurt the dog in any way. I have given it to all my female dogs and I have had green grass with no burnt spots. Go to grasssaver.com there are many sizes to the wafers and they are not expensive. You truly won't be disappointed. It also tells you how to remove the burnt grass as your dog begins the wafers.