My azaleas did not do well near my moisture sucking maple. Lost two and moved the third...its is now much happier. Live and learn :/

you are asking such.. as a designer might place pillows around the room ...

i am a collector... i would only want one of each ...

so basically.. its all up to your whim ...

BUT!!! .. what ho said about digging in plants under huge old maples ...

try once.. but dont keep throwing money at the project.. if they fail ...

ken

The oak would be fine, the maple may give you problems in trying to establish azaleas since both are surface rooting...

But you're in a Z5? I don't grow the Bloomathon, and suspect with my mild climate they wouldn't live up to their name, but the first three descriptions googled show hardy to Z6, indicating you could expect at least some winter damage annually.

With azaleas, I think of an all-one-color planting as a formal one & a mix of colors as informal, more playful. The single color is always safe & uniform, but can be rather boring to me, too, unless the color sings to me. Picking a single or mixed colorway, always helpful to imagine how it will play with other colors in visual range, repeating the color or contrast with other elements. Also consider the strength of the color in various lighting. White shows up in any light, as do those shades of pink & lavender. Red can "disappear" in evening or moonlight, but the cherry & salmon reds often sidestep that issue. When I'm unsure how colors will act, I'm apt to buy the plants in bloom, arrange them & eye them from various vantage points & light exposure until I find what I like best. I'd buy two of each of the colors you're considering from a merchant with a good return policy, explaining why, and give them a tryout in their pots in my yard, returning those unwanted within a day or two. Might buy a few more to land in mixed beds for repetition to knit the garden together.

Also, looks like the size of each is different. Double Pink grows 42-54" high by 36-48" wide, as does Lavender (which you didn't mention). Red grows 36-48" high & wide, so 6" less in height with the same width as the first two. White is the smallest at 30-36" high & wide. so you need to know how much garden space you have & plan on how many of each would mature to that area, whether you want them to touch or stand apart. http://tinyurl.com/ojff984

Various sizes & colors of azaleas planted 20 years ago by the original owner here. There's a long double white hedge along the drive balanced by a triple planting of the same on the opposite corner of the house. Several low-growing reds in a similar shade to the one you're considering were planted along the porch with other low evergreens. We removed & redid that bed years back & carefully relocated some of those azaleas below a clump of mature maples halfway between the trunks & the canopy. They didn't thrive there & were later moved to another location. Keep in mind these had huge rootballs when transplanted, and when removed again two years later, tree roots hadn't grown into their root space. Would think younger plants would grow more easily in a similar situation, since other perennials planted within the roots of the maple clump have done well for years. There was one area where the individual tree roots overlapped & I couldn't find space to plant anything but bulbs (which have flourished & colonized). Planting between major roots has worked fine. If I were thinking about what you're considering, I'd first explore between the roots by digging to find out if planting there would work. When planting in those rootzones, I didn't chop off any roots, anchor or fibrous. Instead dug around them to expose them & held them to the side, putting them back in place as I planted. Knowing wherever you prune a root, more will grow, took this tack. Another mixed perennial bed skirts a large oak & the same strategy was used creating that bed & planting its roses & companions years back.

In my experience, white azalea blooms age the least gracefully, often browning & hanging on - the dirty kleenex effect - and often need to be removed for appearances sake, especially in wet weather. Colored spent blooms are barely noticeable & can be plucked or left for the petals to fall on their own. My favorite azalea planting here is a large mixed bed of reds & pinks & whites around an old apple tree. It's an entire symphony in bloom. Depending on the weather, I often need to deadhead the whites, but they do highlight the other colors & shapes beautifully. If you go with the pink, red & white mix, might place the white in the center for its smaller stature & plant the pink & red at an angle on the sides to fill in with their larger branches. If you want plants of a similar growth habit, you could center the red between the lavender & pink or bookend it with the pinks. If you prefer uniformity, you can always prune the larger ones to shape, but I rather prefer the natural look. If you can swing it, choose several of each in bloom to audition placement till they please you. You could also opt for heavily insulated individual pots or urns to bypass the planting & tree roots issue. Let us know what you decide...

boy did you hit vasue's muse... lol ...

ken