So many great ones that are blue. Halcyon would be a wonderful start. If you have plenty of room Blue Angel is hard to beat. Powder Blue is a bit smaller and a favorite. Mystic Star is mid sized. Gemstone is a terrific small.

Since you are in 7a shade would probably produce the best results. utog and others in your zone would be a better judge.

Here is a link to the Alphabet just to make it interesting for you Hosta Blue 2020

If you have room, Elegans or Krossa Regal. If smaller suits your garden Halcyon

Krossa

Elegans in the back, Halcyon in the front

I agree with the great suggestions of oursteelers and peren.all..I'd also recommend Blue Hawaii and Bressingham Blue..both have done well for me..

Well nw I was going to say Blue Hawaii. But now I will say Blueberry Muffin, Yankee Blue, Waterslide, Prairie Sky, Parisian Silk, Skywriter and that’s all I got!! Lol

debra

I am in NC, 7B. Blues don’t stay blue, but some almost do.
Big: Elegans, Krossa Regal. These both turn green by June, but could last longer in good shady spot. Blue Angel will grow like mad, but will green up quickly. Blue Hawaii grows OK/slow, has nice form, and supposedly holds its blue well all season. My BH is going green already, but I have it part sun next to a brick wall. Jetstream is really good, grows well and holds color well.
Medium: here is where the blue almost stays. Halcyon! Mystic Star (my favorite), Summer Squall, and Tokudama, Camelot, Hovercraft
Small: Deep Blue Sea, Waterslide

Pictured are Summer Squall (front), Mystic Star, Waterslide, and Camelot this morning.

Ooh, yeah. I forgot Waterslide-it’s definitely a good one

Annette, I forgot to mention that Diamond Lake seems pretty awesome in 7B. It is gigantic. I got a little one last summer. It stayed blue until autumn. It is. It is big this year. Blue Tooth is a good small, medium.

I've got Am I Blue, Deep Blue Sea, Ice Palace, Blue Hawaii, Devil's Advocate, Clear Fork River Valley (somewhere) and others. They definitely do better in the shade. Diamond Lake looks interesting.

Diamond Lake yesterday next to Blue Perfection. I do like Blue Perfection as a strong growing fragrant, though I wish the blue lasted longer. Diamond Lake shows a lot of promise for such a young plant.

Rock and Roll. Comes up blue, stays blue, very blue, growing in partial shade here near Boston. It's a slow grower. It grows upright with heavy substance leaves, upwardly cupped and puckered.

I did something odd with this when I ordered it. I think I ordered three. I divided them into small individual plants and put them in the ground apart from each other, to give them room to grow. They have grown, but slowly, so they never filled up the empty spaces between them. I think I have nine separate plants in this photo. I may dig them up and bunch three, three, and three together to get a total of three larger plants, them move two of them to other parts of this big hosta bed.

Wonderful plant. So blue! The sun does not burn this wax off. The color I see on my computer screen pretty much matches what I see in the garden.

I love the blue of that Rock and Roll, I’m gonna have to keep my eyes open for it!

Beautiful cupped leaves on that rock and roll........here’s my Blue Hawaii. Good blue color, in shade so the color stays pretty well.

debra

Prairie Sky has been my best blue but I've got some other new ones I'm pretty excited about.

Waterslide is a good grower and nicely ruffled

Skywriter looks pretty interesting as well.

I‘m making a list. I have some space so will try a few of these. Waterslide, Praire Sky, Diamond Lake, Blue Hawaii, and Rock and Roll to start.

Annette, i tried making a post with pipictures but it didn’t work. will try later

debra

I can see three mentions of Sieboldiana Elegans so far in this thread. The advantage of getting this large blue species hosta is that its seeds are viable and they tend to produce more plants just like the parents. So you get more without having to buy more over the years.

Here's a line of mine on top of a large retaining wall. The left side is denser than the right because numerous seedlings have settled and grown over there, so I need to move some of the children over to fill the empty spaces. All it takes is a shovel, because the dirt here is good. One day soon....

I keep most all of my hostas in pots. This year I have a small blue grouping that hasn't failed to impress every time I go by this spot. It's 'Bulletproof', 'Hadspen Blue' and 'Camelot'

Here they are to the lower left of the picture. Some of the others in this shot are 'Queen of the Seas' which would make a marvelous specimen plant, 'Fragrant Blue' and 'Restless Sea'.. Not to forget 'Blue Mouse Ears' of course.

Here's a closer shot of 'Bulletproof' and 'Hadspen Blue'.

Pieter

Beautiful combination, Pieter.

Get Blue Arrow and stick it in full sun, you can thank me later....

Blueberry Muffin has been a winner in my garden

Okay here’s a couple that haven’t been mentioned yet:

This one is sooooo blue

This is in part sun, the greener parts are from sun.

Two of these have margins but are very blue.

Yankee Blue

debra

One more, My Elegans:

gets some sun

debra

This is Silver Bay. Bunnies really chomped it so looking rough. However its a nice silvery blue and performs well for me.