Everyone's buzzing about their peonies poking through the soil and magnolias in full bloom -- and it's only April.

Perennials are bursting out of the ground so early this year that many gardeners are sorely tempted to put their planting on fast-forward.

"I planted some radishes [in mid-March]; I've never planted that early before," said Lori Erickson, a Minneapolis gardener who starts most of her veggies from seed. "I might even throw some tomatoes out there at the beginning of May, just for the heck of it. Why not? I really feel like this year is going to stay warm."

Others aren't so sure.

"All my master gardener buddies are chomping at the bit," said Catrina Mujwid-Cole, who gardens at home in Minneapolis and professionally as Tinka's Gardening. "But I'm really trying to hold back." She's planted some cool-season crops, including chard, radishes, beets and peas, but will restrain herself from tempting fate with tender plants.

"I don't believe it's going to stay this warm," she said. "We're going to pay for our nice warm March."

Peggy Poore, owner of Uncommon Gardens in Minneapolis, also is wary. "The jury's still out," she said. "April can be kind of twisted."

This year's mid-April forecast includes a couple of nights with lows just below freezing. And Minnesota is still capable of throwing gardeners a chilly curveball; the last frost date as recently as 2009 was May 15.

"Everybody has to decide on their own risk tolerance," Poore said. If your beds are workable, you can try some early planting, she said, but "make sure, when you're buying stuff, that it's hardened off." How do you know? "You have to ask."

Some herbs, such as parsley, thyme, rosemary and chives, can take a little chill, she said. So can cold-season veggies, including peas and onions.

Soil temps

For those impatient to plant warm-season veggies, Shirley Mah Kooyman, botanist and Hennepin County master gardener, recommends first using a soil thermometer to make sure the soil is warm enough for vegetable seed germination.

"The air temperature may be warm, but the soil temperature may not have caught up," she said. Wait until the soil is at least 50 degrees before planting tomatoes, beans or peppers, she advised. (For soil temperature ranges, go to www.aces.edu and type "soil temperature" in the search box.)

"In the old days, we waited until Memorial [Day] weekend to plant," said Kooyman. "This year, the temperatures have been freaky."

Rather than rushing warm-weather plants into the ground, Poore advised taking advantage of the early spring to do other chores, so that you're ready when it is safe to plant.

It's a perfect time to divide and transplant perennials in your beds, said Lew Gerten, owner and greenhouse production manager for Gertens in Inver Grove Heights. "They haven't lushed up yet and you can move them without transplant shock."

Another benefit of this year's early spring: "We actually have a season for pansies so we can rationalize buying them," Poore said.

This year, she had so many customers clamoring for ways to fill spring containers without blowing their plant budget by mid-March that she put out a "garden heresy" press release advising gardeners to buy fewer plants.

"You can create a beautiful container with just a couple of plants and a little creativity," she said. She recommends plants such as tulips, pansies and primroses that can take a chill and find a future home in your garden beds. Then fill in the pots with reusable curly pillow and moss.

Gardeners dying to dig in have more than pansies to choose from. Due to the mild weather, Gertens, for example, plans to offer flats of dianthus, alyssum, snapdragons and other frost-hardy annuals for sale starting April 13, several weeks earlier than a typical spring.

"They can take a light frost," Gerten said. "But if the temperature drops in the low 30s, you should throw a blanket over them."

Protecting perennials

Some perennials also may need extra care if the weather takes a turn. Many peonies, for example, are a full month ahead of schedule, according to Harvey Buchite of Hidden Springs Flower Farm in Spring Grove, Minn. June brides who have their hearts set on peonies may have trouble finding them by then, he noted.

Garden peonies' growth has been erratic this year, he said. "Some are up 8 to 10 inches, and some are not poking up at all."

If we do get a late freeze, peonies will wilt and "look like they're melted," Buchite said. But peonies are cold-tolerant, and those plants will straighten up. "It's important not to touch them in that wilted condition. Leave them alone."

If you know a freeze is coming, you can protect peonies by tossing a sheet over them, or, if they're not very tall, by putting a cardboard box over them, with a weight on top, he said.

The unusual weather means the peony season is likely to be contracted, with more different forms blooming at once, Buchite said. "The neat thing is you'll see combinations of peonies you usually don't."

And if you need a fix of flowers, you don't have to tempt fate by planting your own. You can visit the Eloise Butler Wildflower Garden in Minneapolis, which opened early this year -- April 1 instead of April 15. "The wildflowers are going strong," Kooyman said.

Kim Palmer • kpalmer@startribune.com Lynn Underwood • lunderwood@startribune.com