Two "Left" Green Thumbs

We took a tour around our new home last night. Basically, this was a walk-thru of what's what in the house, what the sellers are leaving and maintenance information...especially for their professionally landscaped gardens. Their garden, which only is about half the perimeter of the house, is FULL of flowers. They made sure that something was blooming pretty much every month of the year, except for maybe December/January. We had a run down of what gets weeded, what gets cut, what doesn't get cut, etc. We even met the two plastic flamingos that grace the side of the house. The seller was very interested in knowing whether I would be keeping the flamingos where they were. I was actually shocked that she wasn't taking them with her....but I said, 'If you're leaving them, I'll let them stay where they are.' I was assured that if I didn't want them, our neighbors would be glad to have them. I'll have to ponder that one.
I was just so excited that there was a hydrangea plant in there - and I learned that if you plant copper (pennies) or nails near the root of the plant, they will change colors when they next bloom. You better believe I will be trying that out!
There had to be over 15 species of flowers/plants that surround this home. It's really lovely. But having never owned a home before, I'm afraid that these flowers are all going to wilt and die...as is the case with any houseplant I've ever tried owning. I have to say, though, that watering them will not be a problem as they have built some underground irrigation system using recycled house water....but the pruning and remembering which flower gets what treatment...I'm not going to lie....I'm scared. Scared that these guys are going to drive by in a year and take one look at the house and say, 'Wow, they really let it go to shit!'