When I started my garden here 30+ years ago, the internet was not built out yet, so I much have gone through $1,000 worth of plants and shrubs the first couple of years, only to find them eaten to a nub or torn up out of the ground. But the two types of daffodils were never touched!—even the ones near the woods. I feed them occasionally and they are still thriving and multiplying.
The only other reliably deer proof flower is the marigold, but they are only annuals. However, they produce abundant seed and even self-sow here and there. Oh, and don't let me forget my gorgeous bugleweed ground cover. It only blooms (to a height of maybe 5 inches) for about three weeks, but it spreads prolifically and soon you will have lots to share. The rest of the year it is a hardy groundcover (Baltimore area). Look here:
