Polly..I am not certain that there are many hosta that I would call a "good spreader". I think there are a few that spread by rhizomes but not many. I think what you may need are ones that increase quickly so that you can divide the clumps often and get more coverage. There are a number of nice blues that are medium small...I like 'Blue Cadet', 'Camelot' , 'Blue Jay', and 'Kiwi Blue Baby'..Look at them on the Hosta Library. Eric Smith developed the Tardianas and there are good blues from this breeding...also Halcyon. Here is 'Kiwi Blue Baby' peeking out from under 'Dick Ward'. I have pictures of other good blues in a friends garden but need to have him come and ID them.
'Dick Ward' and' Kiwi Blue Baby'
I need to ID the rest but you can see there are some nice blues.
'Dick Ward' and' Kiwi Blue Baby'
