Overnight frost could imperil plantings

The National Weather Service issued a frost advisory for parts of Virginia and Maryland late Sunday into Monday and warned that “sensitive outdoor plants may be killed if left uncovered.” Temperatures were expected to dip to the low to mid-30s between 3 a.m. to 9 a.m. Monday.

In the Washington region, the advisory included Loudoun, Fauquier, Frederick, Carroll and Baltimore counties and the city of Frederick.

Depending on the plant, a blanket could help in such situations, according to Francesco DeBaggio, owner of DeBaggio’s Herb Farm & Nursery in Chantilly. “If frost forms on the leaf, it’ll burn that leaf, it’ll burn that tissue,” he said. “The blanket would protect that from frost.”

Still, “if it’s a plant that’s going to be just hurt by cold, you kind of have to cross your fingers,” DeBaggio said.

Zinnias, with their colorful blooms, don’t like the cold, he said. Heartier plants, such as parsley, could be in trouble if they were recently transplanted from a greenhouse, he said.

Many people plant tomatoes, peppers and basil too early, and frost is only part of their problem, DeBaggio said. Mid-May, when temperatures are settled in the mid-50s, is a better planting time, he said.

While a blanket or other cover could prevent frost, it might only raise the temperature a couple degrees. That’s not enough to protect a tomato plant from a blast of cold that, while leaving no visible scar, could stunt its performance later on, he said.

— Michael Laris

Vehicle slams into Metrobus; six hurt

A vehicle slammed into a Metrobus in Northwest Washington on Sunday morning, causing the bus to veer off the road and hit a tree. Six people received injuries that authorities said were not life-threatening.

Metro and D.C. police said the crash occurred about 6:35 a.m. at 34th Street and Woodley Road as the bus was on the 96 route, heading toward the Tenleytown Metro station.

Metro said four bus passengers and the drivers of both vehicles were injured. Officer Paul Metcalf of the D.C. police said no arrests had been made.

— Nick Anderson