When you think of fall-planted bulbs, it's usually the flowering kind — old standards like daffodils, tulips and hyacinth.
But edible bulbs, particularly garlic and shallots, also are becoming popular with gardeners looking to save money and flavor menus.
Good taste is all in the timing for these versatile recipe essentials, especially garlic, which takes months to mature. Depending on location, any time after the first frost or deep into November is the best time to plant.
Temperatures are critical, said Stephen Ward, a horticulturist with Penn State University Extension.
"It has to be cold enough for the bulb not to grow upward, but warm enough so it can grow down into the soil," he said.
That means providing enough time for the roots to develop, yet not enough time for leaves to appear. Mulch with at least 6 inches of straw or leaves to protect the bulb from winterkill. Weed and water throughout the growing season, and harvest when the stems and leaves turn brown in July.
For best results, plant a mix of garlic types and varieties, Ward said. That provides the opportunity to measure their performance under your particular growing conditions.
Garlic comes in as many as 300 different strains from five basic varieties. The varieties — artichoke, silverskin, porcelain, purple stripe and Rocambole — are in turn divided into softneck or hardneck garlic.
Soft-neck garlic has large cloves, robust flavors and tender stems, and does not produce seed stalks. That makes it easy for braiding or tying several tops together, a popular way to dry garlic. Braided strands are attractive, making them practical gifts, too.
Hard-neck garlic is generally mild in flavor and its bulbs are easier to peel. "They are cold-hardy but do not store as well," Ward said.
Garlic can be grown outdoors anywhere in the United States with the possible exceptions of Arctic and Interior Alaska. Some hard-neck varieties can tolerate zone 2.
Shallots, meanwhile, have been described as the gourmet member of the onion family. They need a well-drained site with full sun, since shade slows growth. They don't compete well with weeds and can be grown from seed, but bulbs, or sets, are easier and faster.
Shallots resemble garlic, with heads divided into multiple cloves rather than single bulbs, like onions. They can be eaten as young as 60 days after planting, as you would green onions, or later, like garlic, after the tops die back and the bulbs dry.
Their flavor is described as a mild, subtle blend of sweet onions and garlic. The longer they grow, the stronger the taste. Their foliage also is edible, much like green onions.
Garlic and shallots can be pricy when bought kitchen-ready from supermarket produce shelves. But they come cheap as seeds and sets, said Leonard Perry, a horticulture professor with the University of Vermont.
"Reasons to grow one's own edible bulb crops are the cost savings and even availability — especially with shallots," Perry said. "Also, knowing where your food is coming from and how it was grown, and the ability to try new varieties that just aren't available in stores or even farmer's markets."