Tree Onion. Sometimes a gardener stumbles across a plant so odd, yet so sensible it demands to be spread around to others. Introduced from Canada in the 1800's , the Egyptian Onion is truly a perennial onion, which is delicious in its green tender stage and is harvested like a green onion. As spring continues, it will form small bubils at the top of its 2 foot stems, which become so heavy they eventually pull the whole plant over. The bubil easily pushes roots into the soil and suddenly you have a new green onion a foot or 2 down the way!! The Egyptian Walking Onions will eventually stroll throughout whatever garden bed they are planted in, supplying you with plenty of delicious green onions and even small onion bulbs year after year!!! Onions are often ignored as a medicinal herb, although historically, their healing properties were quite celebrated. Externally, an onion poultice is used for tumors, ear aches, and chest congestion while the juice or syrup is helpful for coughs and the common cold. Edible landscaping at its best. Their unusual growth habit is quite pleasing visually, with vivid green foliage in spring. Egyptian Walking Onions prefer full sun and a richer garden soil. Perennial. Zone 5.