Though not exhaustive, what follows is an example list of vegetables, flowers and herbs typically available in the Spring.
Swiss Chard
Kale
Collards
Mustard Greens
Snapdragons
Nigella
Lamb's Ear
Kohlrabi
Garlic Scapes
Turnips
Radishes
Chamomile
Dill
Cilantro
Head Lettuce
Spring Onions
Arugula
Calendula
Salvia
Bachelor's Buttons