Extension Educator, Horticulture
Iceberg lettuce is a lot like a red delicious apple. True to its iceberg name it has a lot of crunch but not a lot of flavor. Thankfully for our gastronomical pleasure, salads have drifted far beyond icebergs. Arugula to radicchio all kinds of leaves are appearing in salad mixes.
For growing most salad greens the trick is cool weather. Most thrive when the average daily temperature is between 60–70°F. At high temperatures growth is stunted, the leaves may be bitter and the unloved seedstalk forms quickly (called bolting). Early spring or late summer plantings are best.
Beyond iceberg few vegetables are as attractive, tasty and easy to grow as lettuce. The diversity is amazing with colors and shapes of leaves. Seed packets often contain a mixture of varieties.
There are five distinct types of lettuce. Leaf (also called loose leaf), Cos or romaine and butterhead are the most popular to grow in the garden. Crisphead varieties or iceberg types so commonly found in grocery stores are adapted to northern conditions and require the most garden care. Stem lettuce (also called asparagus lettuce) forms an enlarged seedstalk that is used mainly in stewed, creamed and Chinese dishes.
Leaf lettuce is by far the easiest to grow. Some of the most popular varieties of leaf lettuce are the green leaved 'Black Seeded Simpson' and 'Oakleaf' and the red leaved 'Lollo Rosso', 'Red Fire', 'Ruby' and 'Red Sails'.
Cos or Romaine lettuce forms an upright elongated head and is an excellent addition to salads and sandwiches. Popular varieties include 'Cimmaron' with a unique, dark red leaf and 'Green Towers'.
The butterhead varieties are generally small loose heading types that have tender soft leaves with a delicate sweet flavor. Suggested varieties include 'Buttercrunch', 'Nancy', 'Summer Bibb', 'Tom Thumb' and 'Merveille des Quartre Saisons'.
Salad mixes often contain the red leaves of radicchio. Their unique, tangy flavored leaves have been grown in Italy for years. The heads are used in salads, as mixed greens or may be grilled. Although there are many colors and forms of radicchio, the tight heads of wine red leaves with white midribs are most often seen. Radicchio is not the easiest of the leafy crops to grow due to its cool weather requirement. Recommended varieties include 'Rubello', 'Firebird', Giulio' and 'Caesar'.
Another favorite for salad mixes is arugula. As a spicy member of the mustard family it is also known as roquette, rocket salad and white pepper. Roquette was the common name until trendy producers decided arugula was a snappier name. It is commonly used in salad mixes, soups or as a cooked green. Unaccompanied the leaves have a biting peppery flavor that is a bit too much for most of us, but add a zest to otherwise bland foods.
As cool season vegetables most salad greens can be planted anytime in the spring when the soil is dry enough to rake the surface usually after March 1 and again in late summer as a fall crop. Whether you are a novice or experienced gardener, you are sure to appreciate all that growing your own salad greens has to offer.
Check out UI Extension website http://web.extension.uiuc.edu/vegguide/ Also UI publication Vegetable Gardening in the Midwest is a great resource available online at https://pubsplus.uiuc.edu/ or phone 1-800-345-6087.