What's your new gardening zone?

[Rhodie Ranch]

Mine didn't change. 8b

 

[digitS']

Really, @Rhodie Ranch ?

I guess that I hadn't noticed that in your location. You are a long way down the river.

The Dalles, just a hop and a skip upriver from you is the same as here, the map says, 5b.

Steve

 

[ducks4you]

I am still not gonna plant a crepe mrytle!!

 

[digitS']

I am still not gonna plant a crepe mrytle!!

The ones in this neighborhood are in the backyard of a home that I just happen to be able to see – despite their solid backyard fence. Actually, I can only see where they extend beyond the top of their fence. And, the backyard is small so that the trees are very close to a sliding door, also seen below a canopy that likely covers a deck.

It looks as tho they have a tough Winter sometimes. I don't know, probably below 50%. Nevertheless, the fact that they have grown as tall as they have and attract my attention as I drive by with blooms, suggests to me that it is very possible. Choose a protected location for you Mr Ytle ...

That spelling slip was just too difficult for me to resist.

digitS'

 

[R2elk]

Got this email from Montana Fruit Tree Company:

​ ​

​ Something is Not Right, Our Response, Free Talk, Trader Mulberries!​ Hello Growers! Something has been on our minds lately. In fact not lately…for years. But only lately has it begun boiling to the surface. So here it goes. THROW OUT THE USDA HARDINESS ZONE MAP! Right now! Whatever you need to do to get rid it. If it’s printed out and hanging on your fridge (not sure why?), destroy it. If it’s a file of the new USDA updated 2023 map then throw it in your computer’s trash, now! Okay…Whewww! There you have it. That feels a lot better now that that is out. You may be wondering if we are acting a little dramatic. Well, we’re not. All we are saying is BURN DOWN THE SYSTEM! The USDA zone hardiness system, that is. Here we are burning down the system! Well kind of…The USDA zone hardiness map system, that is…of course. You might ask, “But shouldn’t there be something better to replace that which you want to burn down?” The answer is there is! Well, almost. We are in the process of releasing our own hardiness zone map that will actually be of value. So before you take your uncle’s torch (thinking of you Uncle Jake and your 6 hoarded torches), sight tight for just a little longer because our new map should be out soon. But before we discuss our hardiness zone tool and map, let’s recap what the USDA zone system is. Even if you already know, which many of you do, don’t skip this part because there are some important details. Every few years the USDA (euphemistically referred to by Joel Salatin as USDuh) releases updated zone hardiness maps (USDA, 1990; USDA, 2012; USDA, 2023). Hardiness zones and their accompanying maps provide growers with a geographic area defined as having a certain average annual minimum temperature, a factor (apparently) relevant to the survival of many plants. But the key point in that previous sentence is average. This map and rating system has become the standard by which gardeners and growers can determine which perennial plants are most likely to survive the winters in a given location. USDA Zone Hardiness Map. Yeah, not all that helpful. Keep reading to see why it isn’t. However, basing a plant’s winter survivability on its ability to withstand an average annual minimum temperature has SIGNIFICANT downsides. Apart from the USDA’s zone hardiness guide not taking into account other relevant factors such as early Fall and early Spring frosts, the main downside to this approach is that, by definition, average annual minimum temperatures DOES NOT MEAN EXTREME LOWS. Given that extreme minimum temperatures set the range limits of cold hardiness for plants (Strimbeck et al 2015, Geange 2020) and that frequency of extreme winter temps is increasing in some regions, (i.e. through disruption of the polar vortex driving cold cells towards temperate regions (Kretschmer et al., 2018), a hardiness map that takes into account such extremes may provide a more useful tool for northern growers. You see, we have always determined the hardiness of all our trees, shrubs, vines, etc. by the extremes low temps that we know the plant has been able to withstand. But when this number is different from what the USDA’s map says, again because they take the average and not the extreme, then the area where the plant is grown may see much more severe winter temperatures. For instance, Missoula is now rated a zone 5b (and zone 6a in some parts!), which would mean that we see on average between -5F to -15F any given winter. But we just nearly touched -30F in Missoula during the wee hours of Jan. 13 of this year! And we often don’t see -30F temps so that average is pulled up much higher. But all it takes is one winter and your beautiful fruit trees can be toast. So, we must know the extreme low temperautres of a given area, and then couple that with what we know the plant is able to withstand. We monitor all our trees with weather stations so we know exactly the temps they face and what their responses have been. This is where our new tool comes in—a map that users can interface with and see what their minimum low temperatures have been, especially due from severe, advective frost events. We will also include microclimate information. We have run this idea behind several of the top cold climate pomologists (fruit tree researchers) and horticulturists in the country, our friends Bob Purvis and Dr. Jim Walla, and have been affirmed that this tool is much needed. So using Luke’s insight and training from his graduate research in System’s Ecology, as well as help from Dr. David Ketchum and others, we are employing the usage of over 65,000 weather stations across the country to create a hardiness map that better reflects these extremes. So stay tuned for updates as we share this important, much needed improvement to the zone map system and how we think about cold. Two Final things: Luke’s free talk titled Frost!: Growing Fruit Trees in a Cold and Erratic Climate” is coming up! It will be on Fe. 26th at 6:00 pm at the Missoula Library Cooper Space A. RSVP Here We have also added a couple apples to the website including the heritage Winesap apple and McIntosh apples (these were mistakenly never added). Finally, our Trader mulberries are ready and on our site for Fall Shipping. These are perhaps the world’s most cold hardy mulberry and they may go fast! These were selected by the previously mentioned Dr. Jim Walla. Walla had “discovered” and selected these near Oriska, ND from a 150 year old mother mulberry, which was brought over from Germany in 1882, and has survived -44F low winter temps.! Did we say they are delicious! Enjoy the weekend everyone and stay warm! MFTC References: Geange, S. R., Arnold, P. A., Catling, A. A., Coast, O., Cook, A. M., Gowland, K. M., Leigh, A. et al. 2021. The thermal tolerance of photosynthetic tissues: a global systematic review and agenda for future research. New Phytol. 229: 2497–513. Kretschmer, M., Cohen, J., Matthias, V. et al. The different stratospheric influence on cold-extremes in Eurasia and North America. npj Clim Atmos Sci 1, 44 (2018). https://doi.org/10.1038/s41612-018-0054-4 Strimbeck GR, Schaberg PG, Fossdal CG, Schröder WP and Kjellsen TD (2015) Extreme low temperature tolerance in woody plants. Front. Plant Sci. 6:884. doi: 10.3389/fpls.2015.00884 USDA Plant Hardiness Zone Map, 2023. Agricultural Research Service, U.S. Department of Agriculture. Accessed from https://planthardiness.ars.usda.gov/

 

[flowerbug]

Got this email from Montana Fruit Tree Company:
....

while i generally agree with the sentiment they really needed to proofread it.

 

[digitS']

It's understandable.

Who wants to see the fruit tree, cared for over a decade, destroyed by cold. (And, if that is a recent company statement – Montana had some absolutely SEVERE temperatures this Winter!)

It's like for here. It's one thing to buy a couple of geraniums that are supposed to be fine with a zone 5 Winter and quite another thing to put in a 50' hedge of plants with a similar rating and we have a one-in-ten years Winter with minus 20f (-29°C) weather destroy 80% of them.

Steve

 

[Carol Dee]

It looks like I am right on the border of 5a and 5b. Playing it safe we usually plant like we are zone 4!

 

[ducks4you]

I wouldn't trust this as far as I can throw it!
I am 5b6a, NO CHANGE.
I still won't plant a 6b perennial, and you shouldn't jump zones either.
Our latest winters and latest summers have Both been milder than in previous years.
It was back in 1995 that we had a super hot summer, and also in the 1990's that we dipped below -20 for about a week.
Haven't had to use our snowblower this week despite about 5 inches of snow yesterday. Today is cold and sunny, but by Wednesday we will back in the 60's for highs, so everything on the ground today will have melted.

 

[flowerbug]

It looks like I am right on the border of 5a and 5b. Playing it safe we usually plant like we are zone 4!

right, that is why the crocosmia (red lucifer) may not survive in a more open space but will do ok in a more protected spot. ours has now survived over 10 years in the same spot but we did have to replant twice before they survived. i think that is because the bordering cedar trees which block the really cold winds were still small. now they are larger and that creates a warmer microclimate and we have a huge bundle of them now. some sites have them zoned 6-10.

we did have some severe cold snaps for an extended period of time a few years ago but there wasn't any damage i could tell. perhaps the snow cover was deep enough... we've never mulched them.