Each year, Thomas Jefferson competed with his neighbors to be the first to bring peas to the table, a horticultural and culinary victory he celebrated more than once with a dinner of fresh buttered peas at Monticello for the losers. His victory depended in large part upon early planting -- in 1819, he planted peas on Jan. 27.

We don't plant in January, but planting order in Maryland is the same as Jefferson's in Virginia. Peas, spinach and radishes are the first seeds to go into the ground in spring. St. Patrick's Day, March 17, is the traditional pea-planting date, though it can be earlier in mild winters.

"You can put peas in as soon as you can work the soil," says Gene Kelley of Kent County, who has been gardening for most of his 72 years. "Peas like it cold. If it gets too hot, they won't produce."

Peas can be followed in a week or two by leafy vegetables (like spinach, lettuce, chard, mustard and endive); leeks; root crops (including radish, beet, carrot and turnip); and the brassicas, which include cabbage, bok choy, kale and kohlrabi. Early herbs include parsley, cilantro, dill, chervil and chives.

Folksy axioms used to dictate when to put what into the ground. One old planting rhyme instructs gardeners to: "Plant kidney beans if you be so willing, when elm leaves are as big as a shilling" (a little larger than a quarter). Today, planting charts, usually based either on last frost date (air temperature) or on soil temperatures, guide gardeners.

Frost dates vary across Maryland by as much as two weeks. For example, the predicted date for Salisbury's last frost is April 10, while Cumberland's is expected on April 20. Seed catalogs and garden books often have planting charts, or you can call the Maryland Extension Service's Home and Garden Information Center (800-342-2507) for theirs, though it doesn't distinguish between Western Maryland and the southern Eastern Shore.

"The chart is prepared for mass consumption and is on the conservative side," says David Barylski, a horticultural consultant for the information center, which is in Ellicott City. Planting times must be adjusted for different locales.

Soil temperature is a more reliable guide than frost, but requires a soil thermometer, one of those things I always mean to get but never do. (I usually plant peas when the lilac buds begin to swell.) If you do have a soil thermometer, check before you plant. Too cold, and the seed may rot.

"We recommend that the soil temperature for peas be 40 degrees," Barylski says. "And it should be 45 for spinach."

Yet even experts don't always agree. Gurney's Seed and Nursery Co. chart suggests waiting until soil temperature is 50 degrees before putting anything at all in the ground.

Most seed packets indicate planting time, though directions can be vague. For example, the packet for Citadel petit pois (peas) from Pinetree Garden Seeds reads: "Plant 1 inch deep in early spring." For those who aren't sure what "early spring" means, garden writer and lecturer Tina James explains: "Early spring ... is six to eight weeks before the last frost. Mid-spring ... is about a month before the last frost. Late spring ... is the time from last frost until the weather warms up for good."

Some packets recommend planting peas and other early crops "as soon in spring as the ground can be worked." To test whether the ground can be worked, Kelley says, "Grab a handful [of soil] and squeeze it in your hands. If it doesn't stick into a ball, it's ready to work."

In planting any seed, but especially the early season stuff, be sure not to plant it too deep, or it will fail to germinate. As a general rule of thumb, the tinier the seed, the shallower the planting.

"Lettuce should be treated like grass seed," Kelley explains. "You plant it on the top and tamp it in just enough to keep the birds from getting it."

One nice thing about early crops, most of which go rapidly from seed to table (modern peas average 65 days) is that you can do multiple sowings several weeks apart right up until early May. So, if the first planting of peas rots, the next -- or the next -- may thrive.

Jefferson would approve.

Sources:

The Encyclopedia of Organic Gardening

Rodale Press, 1995 (paperback) Has several planting guides throughout

W. Atlee Burpee and Co.

300 Park Ave.

Warminster, Pa. 18974

800-888-1447

www.burpee.com

Gurney's Seeds & Nursery, Co.

110 Capital St..

Yankton, S.D. 57079

605-665-1671

www.gurneys.com

Planting chart based on soil temperatures

Southern Exposure Seed Exchange

P.O. Box 170

Earlysville, Va. 22936

804-973-4703

www.southernexposure.com

Mid-Atlantic planting chart based on frost zones

Pub Date: 03/14/99