For an easy overview of the unfamiliar garden plants you're seeing, you might go to the local public library and look for books about garden plants for your region. And if you're looking for a particular book your library doesn't own, their Interlibrary Loan service can obtain it for you (sometimes charging a small fee). === "Plants for a Livable Delaware" talks about invasive plants which should be avoided, and those which might be substituted for particular invasives. http://www.dnlaonline.org/information/plants_for_delaware.php === The University of Delaware Botanic Garden has -- besides the garden itself -- plant info, events, plant sales, etc.: http://ag.udel.edu/udbg/ === NCSU has wonderful lists of garden plants in various categories (bulbs to trees, and everything in between). I've seen this information in the same format for other states, so I assume there's a USDA database which the states adapted for their particular climates. Unfortunately I could not locate such a database for Delaware (though that doesn't mean there isn't one). Anyway, NC's zones include DE's zones, so the NC database would be useful for you: http://www.ces.ncsu.edu/depts/hort/consumer/factsheets/index.html First, click on the category you're interested in. Then choose whichever arrangement of data presentation is most useful. Don't ignore the "By Scientific Name" and "By Common Name" at the top of each category.

White could mean residue from concrete work. That would be bad if it was shallow. Azaleas have shallow roots so you should be OK. Clay is a concern if there is poor drainage. The standard test is to fill the hole with water and see how it drains if it drains in less than an hour, that is good. Here is a link that might be useful: How to Grow Rhododendrons and Azaleas

I realized you posted 2 weeks ago. Just saw this today. I wonder how it goes. If still nothing, I think it's the seeds. I tried NG impatiens for the first time this year and had no problem in germination. The variety is called "Florific". Actually I think NG impatiens seeds are easier than regular impatiens because they are bigger. I use tofu container, peat moss + perlite, and salad box as the "dome". Don't have heating mat. Just stack the salad box near hot air vent. No watering until the seeds sprouted. The temperature was around 70-72 in the day and went down to 65. So it's definitely on the cold side and I assume warmer setup they should come out faster. Anyway, at 2 weeks my seeds have sprouted, not all of them but majority of them. I don't think they require light because I put my seed trays at the bottom of the stack. In the picture they are 3-week old. Hope you got the seedlings up by now. Otherwise it's probably a little too late to start over.

Where are you located? It could have a bearing on what sort of advice you might get. Ideally, heeling them in somewhere else in your garden would be the best choice. However, it is not the only choice :-) In my area - cool, mild temperatures and usually adequate rainfall - you could store them anywhere the roots are semi-protected. I move or cause to have moved a lot of shrubs due to my business and azaleas and rhodies are some of the easiest to deal with. They get watered well first and then the shallow root balls are lifted and loosely stored in big black plastic garbage bags or other size-appropriate plastic shopping bags, with the bag just loosely gathered around the root ball, leaving the top growth free. Punch a couple of holes in the bottom of the bag to provide drainage and stash the plants out of the way where they will be safe from construction activity and away from the hot sun. Check periodically for water - the roots need to stay just moist, not wet. I have successfully held plants in this manner for as long as 6 months.