Hi. You've got your work cut out for you. Picking the right plants will be a lot of fun though, especially when you see the end results. You have a beautiful yard. Here are some flowers that I grow that you might like:
'Blue Pearl' Jacobs Ladder - mine flowered nearly all of June.
'Vanilla' Marigolds - I start mine about Mar. 15
White Cosmos
Catanache/Cupid's Dart - sky blue flowers, an old Victorian favorite
'Casa Blanca' Lily - white
'Muscadet' Lily - white with wine coloured spots
I bought seeds for a blue Sweetpea called 'Heathcliff' but never got around to planting them. They're supposed to be very fragrant
Cathedral Bells Vine - for your arbor?
White Columbine 'McKenna Giant'
I don't grow these but maybe white Snapdragons?
As for the rose question, I can't help but if you go to the rose forum I'm sure you will get lots of helpful advice. Hope this list is some help. Marg

Hi Marg,

Thanks so much for your reply :-) and yes it was a big help!!!

Blue Pearl Jacob's Ladder sounds wonderful! I have red and also white, but wasn't aware there was a blue variety! I just planted mine this past season (rescued plants). Do you normally start from seed or starts? If seed, have any idea as to the best time to start them for June flowering?

Will start the white Marigolds in March (great idea). I have Cosmos in a few beds in the backyard now... reseeds from last year, but they are just now coming into bloom, so would guess I'll add them to my greenhouse list to start blooming earlier. Would a March sowing be good timing for them as well?

I have several varieties of Lily planted (Casablanca and Stargazer included). This is their 2nd season in the ground, but are just finishing blooming now (Jul-Aug). Should I buy more and start earlier in the greenhouse? Sadly many of my Lily's became expensive gopher food, so will be planting in wire baskets from now on...

Cupid's Dart is a new one to me... so will be checking it out for sure!

I do have climbing roses planted for the arbor (planted this year), but doubt they will be large enough to put on much of a display by next June, so your idea of Cathedral Bells is a good one. Someone else suggested to me planting Hops to fill in for greenery and then adding pots of flowers... might also work...

I've planted several 'snaps' this year in hopes of their reseeding and do plan on starting many more in the GH... so we are on the same page there :-)

Heathcliff Sweetpea also sounds interesting!

I did come across another idea that I thought I'd try to incorporate... Tumbled blue glass. Thought I'd sprinkle it all around in the gravel area (steps and patio/landing)to add some blue sparkle... Of course I have to see 'if' I can locate some :-)
Thanks again Marg for your help! Much appreciated!
Connie

Oh my - of all the color possibilities, BLUE!!! Just wanted to mention to you a product that would be helpful. My niece chose as her wedding color "Victorian Lilac" -- sounds oh-so-easy but it was not. I found an interesting product at the craft store -- it is a coloring spray for fresh flowers. You most often see the florists using a gold spray at Christmas, but it does come in many, many colors (including several shades of blue). I used my "Victorian Lilac" colored spray on Queen Ann's Lace and it looked absolutely fabulous. Very natural and transluscent. Cheating? Yes, but they will never know... I applied mine several days ahead and it lasted through light rain, though you might want to test this out a bit.

How about some hydrangeas? Buy them just before. Endless Summer is a beautiful blue and you can have a hedge of them as a memory of the wedding afterwards.
Set them in pots near where the wedding will happen. Plant them out later. Lowe's has them for $15-$20 per plant.