the gutter has this underground tube that goes like 50 ft away from the house (idk why its so far out but it is lol) so that should be ok ?
excellent, it's that far out to protect the house from water damage, the flip side is that means one of two things; either somebody was into extra preventative measure or the rainwater doesn't tend to drain through your soil quickly &/or there is a high water table...any clue
the wall with the garage door on it is facing the south, and the other wall is facing the west. would hostas to well on the west side? i am also going to plant a bunch of these insane wild ferns my grandma gave us last year because they grow and reproduce so quickly that its not even funny, so im hoping to let them to over an area of the pin. hoping they'll do well on the west side and behind the tree?
Placement is good for sun exposure, as in lots of it, you can't pick a stronger direction, flip side, the water feature and shade plants are an absolute necessity for that placement, don't want to accidently dehydrate and cook your turt. You may have noticed that throughout the day that those are the two sides of the house with the least shade, assuming there are no shade trees in the yard you have picked a full sun location, not a bad choice, but a significant one. Most pond/outdoor water feature people plant for shade or only install ponds in part sun, full sun is algae city, but there are ways around that too. Floating plants water lettuce is nice, hyacinth is fast & easy but may be noxious where you are IDK, maybe check at a nursery near you for info or check online @ your state website.
HJostas prefer part shade, tolerate deep shade and some can be grown in sun but they will scorch and needs extra water. As to the ferns, assuming they're perrenial (dk of any that spread if they aren't) and they spead underground (most do by runners that grow new fern 'cones' but stay attached to the parent) they may be ostrich or lady ferns, any idea how tall they usually grow for you? As to what sun they'll take, ferns tend to like what hostas like, but some (especially the ones with runners like lady & ostrich) tolerate full sun with enough water. Best place to get a good plant list for that location is to look in your phone book for the nearest cooperative exention & see if they have a master gardner service, it's a nationwide free public service for plants & home garders - they'll have the best site specific info, if no luck and you can tell me your USDA hardiness zone (most who garden know that #) or pm me with your zip code (nothing too specific online) I can look it up for you, that # pretty well dictates your plant options. Given that it is a full sun spot, your turt would love a few stawberry plants (lanscape & luch in one tidy plant).
BTW you will want to check on the japanese maple for that spot too, they aren't really crazy about full sun & the smaller finely cut leaved, red varieties burn pretty quickly and often can't survive a full sun exposure.
All of the shady plants would do well under most trees shade wise but they'll need extra water to compete with the tree roots
Nothing not workable, just some thoughts