Can you grow ponderosa pines in hot climates?

[wireme]

In my neck of the woods Pondys are a low elevation species, growing in the hottest and driest parts of the province.
It gets pretty darn hot on the hottest summer days where they grow. It's probably a winter chilling requirement thing. They like low humidity here too I think, very dry air where they grow.

 

[0soyoung]

I'm scratching my head after reading this thread.

• @Eric Schrader says he's got ponderosa in San Francisco, which is USDA zone 10a.
• Portland, OR where there are many outstanding yamadori is in USDA zone 8.
• Houston is in USDA zone 8b.
• Northridge is in USDA zone 10b.
• NEGeorgia is in hardiness zone 7a.

From this I would say that ponderosa ought to be fine in Houston (as far as cold/chilling needs are concerned).

• San Francisco is in heat zone 1 (<1 day above 86F)
• Portland, OR is in heat zone 1 (<1 day above 86F)
• Houston is in heat zone 9 (121-150 days above 86F)
• Northridge, CA is in heat zone 8 (91-120 days above 86F)
• NEGeorgia is in heat zone 7 (61-90 days above 86F)

Given Eric's failures in SoCal, It looks like the heat index may be key. In simple terms, this suggests that in Houston one should keep ponderosa like they keep japanese maples. Gotta keep those roots cool and the entire tree in the shade when temperatures are near 90F and above. We know, of course, that most trees stop growing when the temperatures nears 95F.

One might speculate that the failures in southern locales because day lengths don't vary enough for growth regulation, but the natural stand in the Chisos Mtns suggests that this isn't a problem (there are, in fact, natural ponderosa stands considerably south, in the mountains south of Monterrey, Mexico). As best I can tell, the ponderosa in the Chisos are in heat zone 5 (31-50 days above 86F).

 

[justBonsai]

I was trying to look if I could find local ponderosa from the San Bernardino mountains, but the variety there on average has among the longest needle length when compared to other cultivars.

Looks like I'll just stick to black pines. Thanks for all the info everyone.

 

[mcpesq817]

In Larry Jackel's book, I believe he has care notes from someone in Texas - I forget which city though.

 

[Eric Schrader]

I'm scratching my head after reading this thread.
Given Eric's failures in SoCal, It looks like the heat index may be key. In simple terms, this suggests that in Houston one should keep ponderosa like they keep japanese maples. Gotta keep those roots cool and the entire tree in the shade when temperatures are near 90F and above. We know, of course, that most trees stop growing when the temperatures nears 95F.

Having learned bonsai watering in SF, heat dormancy was something that I didn't really understand until I experienced it. Even so, I don't think shade cloth is a good idea except under extreme circumstances. I have used white cloth on pots to keep roots cool, there are many options that don't involve shading the foliage. And, the cloth may or may not affect heat dormancy. With the Ponderosa's I lost I believe it was roots sitting in wet soil while the tree was heat dormant. Hot-wet roots are obviously prone to rot.

I think Pondy's can take heat, just be aware that they may need less water than you think during prolonged hot weather.
And, I think Ponderosa do not require a hard winter dormancy....but Ryan Neil is on record saying they do. (video from a Chicago demo on YouTube I believe) For the record, we do get about 6 weeks of dormancy on almost all trees.

 

[markyscott]

Thank you Oso - it may work. I like your thoughts about summer protection I'll think about that a bit. In any case, I'll know in a few years - it takes a few before things collapse from exhaustion. My benchmark is 3 growing seasons with a sapling. If I have solid spring growth after three full growing seasons, I'm feeling kind of punchy. If things are still looking good after the fourth growing season, I'm starting to think about an upgrade.

In terms of dormancy, on average, Houston gets 41 days a year where the minimum temperature dips below 40F. On most of those days, daytime highs are in the 50s or 60s - there are very few days were the daytime highs do not exceed 40F. Those days are generally not consecutive either - we'll get a few, but then the cold days are separated by days with temperatures in the 70s or 80s. Always a challenge to know if temperate trees will grow well in Houston. But I know now that there are a number that I wasn't sure about that do well for me - California juniper, Japanese maple, Korean hornbeam, etc. In a few years I'll know about Ponderosa.

 

[milehigh_7]

Having learned bonsai watering in SF, heat dormancy was something that I didn't really understand until I experienced it. Even so, I don't think shade cloth is a good idea except under extreme circumstances. I have used white cloth on pots to keep roots cool, there are many options that don't involve shading the foliage. And, the cloth may or may not affect heat dormancy. With the Ponderosa's I lost I believe it was roots sitting in wet soil while the tree was heat dormant. Hot-wet roots are obviously prone to rot.

I think Pondy's can take heat, just be aware that they may need less water than you think during prolonged hot weather.
And, I think Ponderosa do not require a hard winter dormancy....but Ryan Neil is on record saying they do. (video from a Chicago demo on YouTube I believe) For the record, we do get about 6 weeks of dormancy on almost all trees.

Ryan's a Colorado boy so I trust him...

 

[Potawatomi13]

Here I have 10 Yamadori Ponderosas from Andy Smith , Back Country Bonsai and Randy Knight(collected same areas as the preceding)also Ryan has many very healthy from these same areas in his school/collection. We are Zone 8 here same as portland. There is also a subsp of Ponderosa that actually is adapted to our relatively wet and low altitude Willamette Valley. We do get(too)many freezing nites here with some below double digits and some days below freezing. Randy pots collected trees in pumice and it surely would help "wet feet" problems.

 

[Potawatomi13]

I was trying to look if I could find local ponderosa from the San Bernardino mountains, but the variety there on average has among the longest needle length when compared to other cultivars.

Looks like I'll just stick to black pines. Thanks for all the info everyone.

Washoe Pine, considered by some as subsp? of Ponderosa or Jeffrey pine have shorter needles and smaller cones than either. Can get young ones from ForestFarm Nursery.

 

[Bonsai Orange County]

Hello, this is a thread I’m interested in following up on. Might any of you guys who were going to try growing Ponderosa had any luck to this point 5 years later?
I have the ponderosa in the photos attached (acquired from someone in Portland, OR (oddly enough since I live in Colorado now) and am moving to Southern California (Orange County) next month and want to see if it will make it, and if not is it the heat dormancy or winter dormancy issue or something else. I don’t want to sell the tree and in fact, have only had it for a month, so if anyone feels they’ve dialed in the issue, maybe I could figure out a plan for mine during these times in the future.