Don't dig them up. For the most part, I amend my soil from the top down, and the more I do the more it pays dividends. No hard and fast rules, but I would sprinkle a thin (1-2") layer of either soil or leaf mulch now, and then when the hostas have emerged I'd spread the rest around them individually.

i would not do it ...

do it right.. or suffer the consequences ...

whether or not you MIGHT be able to get away with it.. do you want to risk the loss???

its one thing to throw them on the driveway ...

it another thing to bury a crown which is supposed to be on the surface.. 4 inches too deep ...

especially if you have any of the famous OH clay ...

ken

I can't agree strongly enough with Ken. The plant crown is designed to be at the soil surface, not 4" down. I understand that some people have discovered plants that, when planted too deep, attempted to grow another crown at the surface. However, to the best of my knowledge they were no more that an inch or so deep, definitely not 4 inches. I would think that the chance of survival would be practically zero. But that's just my opinion.

Mary

I don't mean to have given incorrect information. Let me try and be more specific and please correct me Ken and Mary if I have a practice that wouldn't be suitable for Ohio clay.

I would not dig up the hostas to replant on an addition of 4 inches of soil and I also would not pour 4 inches of soil on top of the hostas. My thought was to amend the areas surrounding the plants with soil, say an inch, and then when they have fully emerged I would mulch around them with 2 or so inches of chipped leaves. In this way the crown remains just at the surface, a bit of soil has been added to the bed, and the chipped leaves act as mulch and are wonderful for building the tilth and health of the soil. I'd give anything to see some eyes emerging in my garden right now!

I have done exactly what you are describing,and my plants do way better. The soil is no longer compacted, the soil becomes lite and airy, making nutrients easily available. You can’t go wrong.