Egyptian Walking Onions (also called tree or top onions) are wonderful, unique perennials. These alliums are unique in the way they produce bulblets on the top of their stalks, where most relatives would instead produce just flowers.
The bulblets are edible, as is the stalk, and of course the larger bulbs below the ground. Slightly spicier than typical onions, they may be substituted in most any case for onions when preparing recipes. The stalks are thick and hollow, and similar to scallions. Some gardeners even like to snack on the bulblets while working in the yard!
These heirloom onions get their name from the way they produce their seeds at the top of the plant. As the tops get heavier, they pull the plant down toward the ground and seed nearby areas.
Eventually, this process causes the plants to “walk” farther and farther away from where they started. Left unchecked, these plants will continue to spread and grow, but there are simple steps gardeners can take to control or eliminate the spreading.