Walla Walla sweets, Maui sweets, Vidalia: The names are synonymous with the delectably sweet spring and summer onions harvested for fresh eating.
Their high water content makes them milder than storage onions, so they're great in salads and lightly cooked recipes. Often fetching high prices at the supermarket, they're surprisingly easy to grow.
Onions are sensitive to day length, so pick a variety suited to your climate and plant this fall except in the mountains, where you set them out in spring.
Choose 'Walla Walla' for Northern California to the Northwest and Rocky Mountain regions; go for 'Yellow Granex' (considered a Vidalia if grown in designated counties in Georgia) or '1015Y Texas Supersweets' throughout California and the Southwest.
Sweet onions store for up to two months. Order plants from Dixondale Farms (877/367-1015); they'll be shipped in November.