i would diversify any planting ... you seem focused on all of one kind.. whatever kind that might be ... plant one of each.. and in 3 years.. remove the ones you dont like ... or come to love them all ... ken

Wow! Now that's a 'timber-type' pear! Boy, if there was an instrument-maker or wood-worker in the neighborhood, and you could have that sucker sawninto veneer-quality lumber, it'd possibly be worth something - but most timber-cutters wouldn't want to come within 20 miles of trying to extract that sucker from that spot. Looks like a job for an accomplished, bonded/insured arbor service - not just cuz'n Bubba with a chainsaw.

Hi - I just brought home yesterday a #3 pot Annabelle as I'm probably the only one in our z5 (I'm just 30mi S of z4b) without one. Annabelle, from reading testimonials in this forum is a trooper even for z3 & can take both sun & shade. Silvergold has one and looks gorgeous with her other H paniculata - also hardy for our zone (seen pics). Also fits your bill for 5'hgt limit. I'm sure your "landscape guy" will know where to put the Hs. I love my 2 Tardivas - known for their late blooms but because both of mine are in full sun exposure (planted with blooms in '05) in '06 & '07 both started flashing with their airy, creamy white, panicles in mid Jul, does not flop down either and also easy maintenance ... no Winter cover-ups needed! One of them is a bit over 6'tall x 5'wd, the other is 5.5'tall x 4.5'wd. I have no experience with Unique. BTW ... "Can a 'brown thumb' gardener grow hydrangea ..." Here's a LOL analogy ... I was just clipping the old brown canes of my hydrangeas yesterday (given up for dead) ... found that underneath the brown skin was the greening, live, inner skin. So your 'brown thumb' may exfoliate & won't be long, before your 'green thumb' may just surprise you. You see Hydrangeas have a way of working on the most doubtful of Thomases!!! Good luck & have lots of fun with your new foundation bed!!! :-)

Typically, as soon as the foundation is built and braced or the first floor is on, it's backfilled for the safety of the trades on-site. When it comes time to install drains and the water line, which often run together, the backhoe digs and backfills again. No big deal, no placeholders needed. BTW, that seems a problematic place to run a water line, where it may be vulnerable to backfilling damage and frost if you're in a cold or very cold climate. In any case, check with whomever brings in the supply what their procedure is, listen and follow it.