MELISSA BLOCK, HOST:
From NPR News, this is ALL THINGS CONSIDERED. I'm Melissa Block.
ROBERT SIEGEL, HOST:
And I'm Robert Siegel.
If you live in the Northeast, this has been one wacky winter. And as some of you may be noticing in your own front yards, plants are responding.
NPR's Margot Adler lives in New York, where temperatures have risen into the 50s, and she went in search of February flowers in bloom.
MARGOT ADLER, BYLINE: At the New York Botanical Garden, I was not disappointed. There were bushes of red camellias and gorgeous yellow flowering Adonis. Kristin Schleiter is the acting director of outdoor gardens here. She's taken me to an outdoor test garden.
KRISTIN SCHLEITER: This is our ladies border, which was planted beginning in 2001 with the idea of trying to sort of push the zone and see if we couldn't get some plants through the winter that maybe don't typically come through the winter.
ADLER: And we are looking at all this flowering beauty.
SCHLEITER: A good proportion of the things are doing fabulously.
ADLER: The garden is south facing and a bit sheltered, which makes it more possible for plants that normally thrive in Maryland and Delaware to thrive here in New York. A Japanese apricot tree has been blooming here since the last week in January.
SCHLEITER: And it is a beautiful middle pink. It's fragrant as all get out, and the bees love it. They're just all over it.
ADLER: Even now.
SCHLEITER: Even now. As soon as it started opening, the bees appeared.
ADLER: You can't judge anything long term by this warm winter. Last year was bitter cold. But looking at these flowers and trees, some thriving for 10 years, gives pause.
SCHLEITER: There is a shift to the warmer. Absolutely, yes.
DAVID WOLFE: We're having earlier springs.
ADLER: David Wolfe is a professor of plant and soil ecology in the Department of Horticulture at Cornell University. In his own research...
WOLFE: We looked at historical records for the first bloom dates of apples, grapes and lilacs, and documented that all of those species were blooming four to eight days earlier, going from about 1960 to 2005 or so.
ADLER: You may be wondering how all these earlier springs relate to the new USDA hardiness map that just came out. They don't.
KIM KAPLAN: You can't use this map to judge climate change.
ADLER: Kim Kaplan, a spokesperson for the Agricultural Research Service of the USDA, says it's simply not the appropriate tool for that. The new map does put many areas into a warmer zone than previous maps. The map uses data collected over 30 years. The previous map only looked at 13 years.
The map only gives measurements for low temperature. You need lows and highs to really measure climate. And the map is so nuanced and covers bodies of water and different elevations with a complicated algorithm, so there isn't anything to compare it to.
KAPLAN: Is a change in zone due to the greater accuracy, because of the algorithm, to the greater resolution, because it represents a hotter spot or a cooler spot that we couldn't pick up before? Or is it due to the additional years of data?
ADLER: So better indicators are the patterns of insects and birds and plants over years. David Wolfe says while farmers have to be careful - their livelihoods often depend on being right on what and when to plant...
WOLFE: You know, I think it's definitely time for gardeners to think about experimenting in the garden.
ADLER: Gardeners could take a few more risks, he says, and be at the forefront of the great experiment in finding out what's now possible to grow.
For the rest of us, a winter garden in bloom may fight winter blues.
SCHLEITER: So there's a late winter, early spring place to come at the New York Botanical Garden when you're just - really need some flowers.
ADLER: Margot Adler, NPR News, New York.
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