The USDA's gardening zones have shifted. (Interactive app and map) (2024)

comrade1234 7 minutes ago | parent | next [-]

I have property in NW WI and I planted 5 paw paw trees. I had heard that there's a paw paw in Madison so I had hope. I bought them from a tree farm in MI that said they had discovered a cold-resistant paw paw.

One of them survived over five years now! It's still really small but I think it'll make it. Even if it grows up there's two problems - the summer may not be long enough for it to produce fruit. And two, they reproduce by sexual reproduction. The only way it will produce fruit is if there's another paw paw in the vicinity.

I wanted to plant another batch of trees but when I went to the website of the tree farm there was an announcement that they retired - that they ran the farm for 50 years and it was time to retire. So no more cold-hardy paw paw.

I live in Zurich which is about the same latitude as NW WI and there's a bunch of paw paw trees at a tennis club near my house. They produce copious amounts of fruit. And there's constantly random new paw paw trees sprouting up. But the weather is much nicer here.

Maybe some day the weather in NW WI will be mild enough to match Zurich.

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starkparker 2 hours ago | parent | prev | next [-]

(2024), via https://www.npr.org/2024/05/13/1250855166/big-news-for-garde...

Further context from 2023: https://www.npr.org/2023/11/17/1213600629/-it-feels-like-im-...

	▲	altairprime an hour ago \| parent [-]
		(2 years ago, 218 comments) https://news.ycombinator.com/item?id=40342578

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nmbrskeptix 2 hours ago | parent | prev [-]

This is weird. This represents a change over a mere ten year period.

My zone hasn't changed (still 6b), but USDA states the lowest T has gone up 5F (-10,-5) to (-5,0).

Last winter we had -10F for a week. This winter we had -20F for a week.

What I find strange is that the interval from the last assessment is small, only 10 years. And yet in two of those we broke records in the opposite direction of that reported. Note that USDA is not reporting the average, but the coldest temps likely to be encountered.

Even if the winter is trending warmer, I would think two record breaking cold winters in a ten year span would change my local data downwards, not up.

This has affected me. For three years I have tried planting chicago hardy figs. For three years we've had chicago like winters and the figs didn't make it (chicago hardy needs a couple of mild winters to withstand chicago temps).

What do I know? YMMV

	▲	zamadatix 29 minutes ago \| parent [-]
		"Hardiness zones in this map are based on the average annual extreme minimum temperature during a 30-year period in the past" https://planthardiness.ars.usda.gov/pages/how-to-use-the-map... (the page also reflects this in one of the sections). So it doesn't matter if it was -20 F all year or for 1 day, either counts as 1 value of -20 F out of 30 annual measurements to be averaged. 2 record breaking cold winters out of 11 wouldn't necessarily imply much with over 1/3 of the averaged data being replaced (it'd depend more on the 11 years replaced than the 2 new extremes), and that should show in the graph of the exact yearly values used towards the middle. I do sort of wish it opened with the deeper explanation of what the data is first and then got to showing you the values second. Giving someone numbers, having them try to interpret them, and then telling them what it was the numbers were actually trying to measure is a recipe for creating confusion.