dead zone

I seem to have aquired -for lack of a better word, a dead zone in my garden. My Poppies came up but quickly turned brown and faded away. Then the Daylilies nearby wilted and only a few came up. I dug up the rest of the Black- eyed Susan's bordering on that spot, replaced the soil and added peat. Then I planted Astilbe there (well established plants that were $$) thinking it was just not enough sun perhaps in that spot, but now they are turning brown as well. I have been watering everyday since planting the Astilbe. I also have no pets that are frequenting that area...any ideas?

Any chance there's a natural gas supply line in the immediate area? A chance that a vegetation killer (soil sterilizer, not Round-Up or equivalent) was used in past years - perhaps instead of Round-Up?

Al

Now that you mention it, my neighbors have started using TruGreen on their already dead grass. Seeing that my new "deadzone" is just on the other side of their fence might be a clue! Thanks, I don't know why I didn't think of that. But now what can I do?!

Try annuals in pots in that area or yarden art.