Most edible flowers fall into what I call the "barely edible" category, meaning they won't kill you, but they don't taste especially good either. That said, there are a few flowers that are actually worth eating, look pretty on the plate and attract beneficial insects to the garden.
Some of the best edible flowers are simply the blossoms of vegetables and herbs, including mustard greens, arugula, dill, and mint. I always let these plants flower because they are pretty, attract beneficial insects and pollinators, and they taste good. Most edible flowers are too delicate to wash and do not store well. Instead, pick them just before you plan to use them, brush off any soil and check carefully for any insects hiding within.
Nasturtium
I sow nasturtium seeds at the edge of beds because they grow into pretty, blousy plants that spill over the margins. Both the leaves and the flowers of nasturtiums have a delicious spicy flavor that tastes especially good in salads. I also sometimes stuff the blossoms into sandwiches, along with herbed cream cheese, slices of tomato, and lettuce.
Calendula
The petals of calendula (also called pot marigold) look like confetti when scattered across a salad or plate. Calendula produces loads of flowers from spring through fall, though it helps to snip off flowers as they fade to encourage more blooms to form. Be sure to let some of the flowers go to seed, because calendula self sows easily, which means that it will come up all on its own the following spring.
Arugula
Arugula blossoms have pretty crepe paper-like white petals with dark purplish black veins. The flowers taste spicy and nutty--just like arugula greens--and make a pretty garnish. I like to scatter them over salads.
Squash Blossoms
Squash have both male and female flowers on the same plant. Female flowers have a little squash just behind the blossom. Both types are edible and taste delicious stuffed with cheese or added to a quesadilla. Pick the blossoms in the morning when they are just beginning to open. The blossoms taste like a very delicate version of squash and they will store for a couple of days in the fridge if placed in a plastic bag lined with a damp paper towel. You can eat the blossoms of any summer or winter squash variety, including pumpkins.
Dill
Dill flowers are actually an umbrella-shaped compound flower composed of many tiny blossoms. Dill is especially attractive to beneficial insects and pollinators because the flower's shape makes it very easy for them to access the nectar and pollen. The flowers have a light dill flavor and they retain their shape and color quite well when added to jars of cucumber pickles. They also make a pretty garnish in a drink or on a plate.
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Willi Galloway writes The Gardener column. She lives in Portland, Oregon and writes about her kitchen garden on her blog DigginFood. Her first book Grow. Cook. Eat. A Food-Lovers Guide To Kitchen Gardening will be published in January 2012.
(Images: All images by Willi Galloway)
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I just planted a bunch of Nasturtiums for the first time this year - really excited for them, and I've heard that they will re-seed and come back by themselves next year.
Rosie, indeed they will. The seeds form in three-chambered pods (like a trefoil). Just wait for these to fall to the ground, and you can gather the seed, which are somewhat like a wrinkled cherry pit, but a bit smaller. Let them dry and add them to your seed collection. They'll sprout easily.
Nasturtium produces a lot of seeds, and unless you get them all, some will stay around in the soil until next year. For this reason nasturtium is considered invasive. (However, the roots are shallow, and the seedlings easy to identify and remove when they sprout, so don't worry about it - it's not a permanent invasive like mint or morning glory.)