Onions, garlic, and their kin are delicious, versatile staples of cooking and eating that are easy to grow in any garden. We tend to take these pungent plants for granted because they’ve been a staple in dishes around the world for thousands of years. (Be sure to check out our Roasted Garlic and Onion Soup recipe.) Allium species number in the hundreds, and include many ornamentals — think giant purple globe-shaped blooms held aloft by sturdy stems. Here, though, we’ll focus on the flavorful garden vegetables with edible bulbs, stems, or leaves.
You’ll often see onions listed for sale as “long-day,” “short-day,” or “intermediate.” Knowing your day length (the amount of hours of sunlight in a day) will determine which type will form the best bulbs in your geographical location. Long-day onions are best for colder, northern climates, and require a day length of 14 or more hours for bulbs to form. These onions are planted in spring. Short-day onions require a day length of 11 to 13 hours and are generally grown in warm, southern climates. They may be planted in fall and will grow through the frost-free winter months. (Most growers consider 36 degrees latitude to be the dividing line between long-day and short-day onions.) Intermediate (also called day-neutral) onions require 13 to 14 hours of daylight and can perform in nearly any type of climate.
Onions can be grown from seed or from a group of small bulbs, known as a set. Most heirloom cultivars are available as seeds. If you live in an area that isn’t frost-free, you’ll want to start your onion seeds indoors 10 to 12 weeks before hardening off the seedlings and transplanting them into warm soil.
‘I’itoi’ is a multiplier onion that produces many small bulbs in a clump (pictured below, right). It was brought to the Colorado basin in the late 1600s by Jesuit missionaries. The young greens pack a bit of heat, while the bulbs are mild and good for both cooking and eating raw.
‘Red Welsh’ is an extremely hardy bunching onion, grown for its large greens and white stem. Bunching onions do not produce bulbs. ‘Red Welsh’ is Asian in origin and was brought to England in the 1500s.
‘Tropeana Lunga’ is an intermediate onion originally from Tropea, Italy. Its elongated, reddish-purple bulb (pictured below, left) is widely used in Mediterranean cooking.
‘Bianca di Maggio’ is a long-day cipollini onion from Italy, characterized by its flat bottom; small (but plump!) size; and thin, creamy-white skins. This sweet onion is excellent for pickling or eating fresh.
Egyptian walking onions are often grown as annuals, and will produce small bulbils, which may be removed and replanted. In milder climates, you can grow the plants as perennials and allow them to “walk”: The top-heavy bulbils will bend the stems down and take root where they meet the soil. The greens of Egyptian walking onions are bold and mildly spicy; you can eat the bulbils as well as the bulb that grows underground.
Shallots (Allium cepa)
Shallots are typically classified as one of two types: true and hybrid. True shallots are the best selections for cold regions and are planted in spring for late summer or fall harvest. Shallots that are hybridized with onions are grown from seed, and are often categorized alongside multiplier or potato onions. Hybrid shallots are good candidates for warm climates and may be planted in fall. All types of shallots have a sweeter, milder taste than onions.
Dark, red-skinned ‘Prince de Bretagne’ shallots from Brittany, France, are coveted by cooks but hard to find in the United States. These shallots have a mild flavor suited to eating fresh in salads.
‘Zebrune’ is a so-called banana shallot because of its elongated shape (pictured below, left). In France, this hybrid’s resemblance to a chicken leg means that it’s called ‘Cuisse de Poulet du Poitou.’ The skins are brownish-pink in color.
Leeks (Allium ampeloprasum)
Grown for their tasty, enlarged stems, leeks may be started from seed indoors in winter for spring planting. They require fertile soil and generally prefer cooler temperatures. To obtain the desirable blanched-white stem, plant leeks deeply and mound soil against the stems as they grow taller.
‘Giant Musselburgh’ was first introduced in Scotland in 1834. This very large leek (pictured in slideshow) produces stems 2 to 3 inches in diameter. One of the most adaptable leeks to any climate, it performs best in cooler temperatures.
‘Bleu De Solaise’ is a 19th-century French cultivar. At 15 to 20 inches, the plants are shorter in height than many other leek cultivars, but produce very thick stems.
So-called “elephant garlic” is actually a leek relative. In mild climates, elephant garlic sets may be planted in late fall or early winter. You can choose to harvest plants the following summer, but the bulbs you dig may not contain multiple cloves. To consistently obtain more than one clove, allow the bulbs to continue growing into the following year. Elephant garlic is a perennial in warm zones. You can keep harvesting some of the bulbs of the ever-expanding plant year after year.
Garlic (Allium sativum)
Although a more specific classification exists for garlic, most gardeners are familiar with the general designations “hardneck” and “softneck.” Hardneck garlic (A. sativum subsp. ophioscorodon) is characterized by its scape, a curling, flowering stalk that issues from the center of the bulb. The scapes are edible and have a mild garlicky flavor. If the scape is left untouched, it will produce bulbils that may be planted. Hardneck garlic is best suited to cold climates. Softneck garlic (A. sativum subsp. sativum) rarely produces bulbils, has larger bulbs containing more cloves, and stores longer than hardnecks.
In regions that experience frost during the winter, garlic is most often planted in the fall for harvest during late summer or early fall the following year. As with other alliums, it’s beneficial to apply a layer of straw or other organic mulch to your new garlic plantings.
Hardneck ‘Chesnok Red’ originated in the country of Georgia. Its large, purple-striped bulbs (pictured in slideshow) are easy to peel.
Softneck ‘Lorz Italian’ was brought to Washington state from Italy sometime before 1900.
‘Spanish Roja’ is a spicy-hot hardneck garlic that reportedly arrived in the Pacific Northwest in the 1800s. It falls into the rocambole group of hardnecks, which are highly desirable due to their bold, complex flavor.
These seed companies are great sources for edible allium bulbs you can grow in your own garden.
Sheryl Normandeau is a freelance writer and homesteader from Calgary, Alberta. You can follow her gardening adventures on her blog, Flowery Prose.