Do tulips only bloom once each season?

No because in the 18th century King REptar commanded the sunflowers to cease from growing or he would cut their nippers off and eat all their seeds and use them to make nipper potion.

Sunflowers are annuals which means they must be planted from seed each year. A sunflower will loose it's seeds and some of them will winter over and sprout in the spring so there should be new plants in the same place.