Esther,

There is a variety of impatiens called "Sun Patiens" that does not get the powdery mildew. Along with New Guinea impatiens they do well in both sun and shade and are relatively disease free.

As for "big flowering" perennials, that's tricky. Most of the shade perennials don't have large flowers. Astilbe does. I think certain kinds of Astilbe goes well. Here's On Stage with Astilbe in the Cochato Nursery Display Garden. This might be a good combination to try.

As for 20" diameter Hosta, you're talking about smaller plants and you probably need the mini-heucheras to go with them. Rainforest Sunrise is a definite. Any of the Tiaras would work especially Grand Tiara with it's wide margins. Lakeside Paisley Print is a lovely small Hosta. And you may be able to use a large upright variety like Gold Regal. That might look nice underplanted with a few Pulmonaria (blue and pink flowers).

Have fun.

Steve

Corydalis, there are several varieties and colors. Corydalis Lutea, yellow, blooms all summer for me.
Brunnera, when it blooms sky blue forget me not type flowers, is unforgettable.
Astilbe, pinks whites or reds, stand tall love shade.
Cimicifuga come in tall varieties for the back of the garden, and smell heavenly. Lobelia Cardinalis another tallish, vibrant red, if your ground is damp enough.
Primrose, Epimedium (can be pricey), Pulmonaria, Anemone, Columbine, Ferns...

STEVE, thanks for your input. I already have Rainforest Sunrise in my own garden and I agree, it's a stunner. And Paisley Print is somehow gonna be squeezed into my garden as well. But those ARE the size I'm talking about, yes. I have 2 varieties of Astilbe, but their flowering period is really short, disappointing me.

UNBIDDENN, I am familiar with some of the plants you mention (thank you!), but I am going to run down info on all the others, plus sourcing. Our best Queens nursery has just sold itself to the city, the land to be used for an elementary school that no one seems to want in the neighborhood--go figure. So I will have to go out to Long Island to a venerable nursery to get some of the more "exotic" perennials, if my friend decides that's what she wants in the garden.

The picture you posted is just lovely. Just love your heuchies. What varieties of heuchie am I seeing?

Caladiums and coleus are two I use for different color. I am not sure how caladiums will do for you but it was an inexpensive color blast. Coleus would have to be replaced yearly but seeds freely here. Have fun with a new garden

Peach Melba right up front, Snow Angels behind it. Citronelles to the left of Peach, Raspberry Ice (purplish) behind Citronelle and in front of tiarella Pirates Patch. Pinot Bianco is a pale green next to a tuft of darker green, which are really three large Sashay. Above that you can barely see Hosta Pineapple Upsidown Cake. below the maidenhair fern is a paprika at its worst, to its left Sugar Plum, and left again Southern comfort you can barely see the edge of. Autumn Frost, a new division is kinda under the Japanese maple. Thats only what i can pick out to the left of the stepping stones, in the first picture I posted. I have heuchera issues, badly.

Above is Spellbound

Well, Unbiddenn, I adore heuchies as much as my hosta. I have Georgia Peach, Autumn Leaves, Marmalade, Paprika, Rio, Midas Touch and several of the Cuties (Frost, Peppermint, and sugar Berry. I hope that Terranova creates more Cuties for my small space so I can snap them up. I also want Ginger Snap (mine didn't make it) .

Nice garden pic, Unbiddenn! That's quite beautiful.

Don B.

ilovetogrow, please tell me, what is the upright, cupped hosta in the blue pot?

Ester, Asiatic lilies and Martagons grow in some shade, have big flowers and fit easily between hostas.

As for small hosta, of the ones I grow I recommend Tickle Me Pink and Tongue Twister.

Its always fun to think about a new project, thanks for sharing.

Beverly

Beverly,

Just an FYI. Here in the East it's difficult to grow Asiatic lilies due to the Red Lily Leaf Beetle. It can be done, but it involves a great deal of hand picking of some really disgusting fecal-covered larvae. If these are not removed they will eat the Asiatic foliage to the ground. Be thankful you don't have these pests (yet). I haven't tried Martagons, so I don't know if they are susceptible to the RLLB. Oriental Lilies are fine.

Steve

Terri that is a still unfurling Elegans. Here is a photo taken late in August. Thank you for asking. Paula

Sounds absolutely disgusting, Steve. Thanks for the heads-up about this nasty little insect, though. If my Asiatics start getting attacked, these'll be the first things I look for. Hope they don't make it this far west, but you never know, eh?

Don B.

P.S. As Beverly mentioned though, Asiatic lilies do grow quite nicely in part sun/bright shade. I was pleasantly surprised to find they will grow and blossom well right alongside hostas. Sorry the pic is a bit washed-out.

Thank you Paula. I do have Elegans--it was one of my first hostas. I will have to pay better attention to it when it unfurls this spring--yours was just gorgeous!
Terri

One hosta that can give a really lovely floral display is PURPLE LADY FINGERS. Talk about lovely! I only have two in containers (from Hallsons) and last year they put on a nice display for a couple of weeks. Of course, no reblooming. Not large hosta.

Then one which gets somewhat larger and has stunning bloom scapes is HOLLY'S DAZZLER.

Both are greenies.