I'm new here and new to gardening!
My wife and I recently purchased our home about four months ago. Once the weather started getting better (we're in Chicago), I went to Home Depot to get some trees and shrubs for our new place. That was prob 3 months ago? I try to water them twice a week but over the past month it seems like they are getting progressively worse. About two months ago I tried the fertilizers where you punch into the soil. Over the past months I've tried watering more (~3 times a week) and also bought fish meal to supplement (~1 weeks ago), but the plants don't seem to be improving and in fact seem to be declining. I'm wondering if someone more experienced can help with my questions/hypotheses:
1) How do I check whether issue could be soil quality? Most of the soil is from the developer.
2) The guy at Home Depot says they're spaced far enough apart -- does the spacing look correct?
3) What's the optimal watering interval? Is there an easy way to check whether the plants are getting enough water?
4) I think the plants are getting enough sun light (unit faces southwest). Does it look like it?
5) Any idea on whether one of the trees seem to be doing better than the other (in both locations)?
6) Is the space large enough for these trees?
I'm out of further ideas so any help or tips are welcome. Thanks so much!