When you say you fertilized, did you fertilize enough for what you planted? A soil test would have told you how much fertilizer you'd need.
I suspect you might have no had enough N in your first planting. When I plant I'll do an initial fertilizing similar to what you did, then once the plants are around knee high I'll top dress around 100 pounds of "urea", aka "46-0-0" per acre right before a big storm comes in (need rain to work the urea down in the soil).