The unusually high temperatures have made it feel more like spring than winter in recent days. People who enjoy milder weather love it, but it’s causing some concern for gardeners, and plenty of confusion for some plants, which have bloomed several weeks earlier than usual.

“Once it stays warm for a prolonged period of time, the plants break dormancy and they begin their spring growth,” says Paul Meyer, the F. Otto Haas Director of the Morris Arboretum.

Across the Philadelphia region, crocuses, daffodils, magnolias, and other plants have sprung up as if it were already springtime. But spring doesn’t officially arrive until March 20.

Meyer says any time the weather deviates dramatically from the norm, “it usually spells stress for plants.” If the weather turns very cold in the next few weeks, and there’s a significant snowfall before spring officially arrives, many plants could suffer damage.

Meyer says plants will be less tolerant to cold weather in March than they would have been earlier in the winter, when their embryonic cells were in a protective dormant stage.

People, plants, and animals are at the mercy of Mother Nature, but Meyer says there are ways to protect plants if the weather takes a glacial turn. To shield plants from the cold, Meyer says gardeners should cover them with a tarp or blanket in the evening to help retain heat and guard them from freezing. But the covers need to be removed in the morning to prevent the plants from suffocating.