Mugo Pine conflicting grow zone info.

[AcerAddict]

Some websites say standard Mugo (Pinus mugo) is only suitable up to USDA zone 7, but other sites say zone 8. NC State University's info page (link) says Mugo is OK up to zone 8a, which is where I'm located. I worked at NC State for a number of years when we lived in the Raleigh area, so maybe I'm a little biased, but since I live in NC, I want to trust their information. I've found the same conflicting info for Dwarf Mugo (var. pumilio) as well, with an almost even split between zones 7 and 8 being recommended as the max. Is standard or dwarf Mugo preferred over the other for bonsai use?

It gets too hot and humid here in the summer for a lot of pines, so I'm trying to make a short list of what would be OK for me, just one mile from the Intracoastal Waterway. Other than the obvious Long Leaf Pine (whose leaves are TOO long!), I've found that JBP, Shore Pine, and Ponderosa get the green light for zone 8. Shore Pine in particular can handle salty air without skipping a beat.

@Vance Wood, I'd like to know your thoughts on this as well please.

 

[Potawatomi13]

These northern European trees. Considerably colder than zone 7. Everybody grows these here in yards. If your area very humid "could: be a problem.

 

[ShimpakuBonsai]

I don't have any Mugo growing as a bonsai but I have a few growing in my garden for the last 25 years.
I treat them as Niwaki trees and I cut the candles every year to compact those trees.
Mugos are sold in almost every garden center in the Netherlands and most of the country is zone 8.

 

[Shibui]

The conversion calculator says I am in zone 9, possibly even 10. Pinus mugho grows quite happily on my benches. Mine has grown here for around 25 years since I struck it as a cutting. I'm currently looking after another older one for a friend so that's 2 votes for mugho tolerating warmer zones.
Summers here are hot but usually quite dry which could make some difference

 

[AcerAddict]

Thanks for the feedback. I think the humidity may be the deciding factor here as opposed to temperature. We frequently have humidity in the 80% and even 90% range during June, July, and August. While this is great for sub-tropical species like Crape Myrtles, it's not really good for most pines unfortunately.

We only have six species of pine that grow natively in North Carolina (link), and out of those, only three grow naturally here at the coast where I live. I've only ever seen one of the six made as a bonsai, which was a Loblolly Pine.

 

[Colorado]

Thanks for the feedback. I think the humidity may be the deciding factor here as opposed to temperature. We frequently have humidity in the 80% and even 90% range during June, July, and August. While this is great for sub-tropical species like Crape Myrtles, it's not really good for most pines unfortunately.

We only have six species of pine that grow natively in North Carolina (link), and out of those, only three grow naturally here at the coast where I live. I've only ever seen one of the six made as a bonsai, which was a Loblolly Pine.

I have seen a few Eastern White Pine and Pitch Pine also.

Never even heard of Pond Pine but sounds interesting.

I feel like we are going to see more and more of these Eastern US species being explored in the coming years.

 

[A. Gorilla]

Hey bucko, why don't you just stay in your lane and spare us all future whining about a tree in mysterious decline?

I dont screw with JPB, olives, trident maple, azalea, etc, so how about you leave the frigid species to those who can unambiguously accommodate them?

Peak millennial. Have your parents ever said no to you?

Fight me.

I'm sorry, that was harsh.

I do want to fight you though.

 

[PA_Penjing]

The hardiness zone is no indicator of whether or not it will be happy. If you can find an upper limit to the heat zone that will tell you more. Zone 8 Oregon is probably great for mugo, well it might be a little too wet... but regardless zone 8 NC is going to be a lot hotter. And the heat is the issue. I don't understand why the hardiness of trees is described in a cold hardiness limit and then max. For example there are palm trees growing in the ground in Whitstable, England because the winters aren't very cold. But the summers are super low key, like room temprature. My best advice for Northern species is to get them in full sun while they break bud and harden off, then move them to dappled shade for the summer and cover the pot with a breathable material when temps get real high. That way they keep compact growth while staying somewhat cooler. I have only done this with spruce so mugo might be different

 

[AcerAddict]

The hardiness zone is no indicator of whether or not it will be happy. If you can find an upper limit to the heat zone that will tell you more. Zone 8 Oregon is probably great for mugo, well it might be a little too wet... but regardless zone 8 NC is going to be a lot hotter. And the heat is the issue. I don't understand why the hardiness of trees is described in a cold hardiness limit and then max. For example there are palm trees growing in the ground in Whitstable, England because the winters aren't very cold. But the summers are super low key, like room temprature. My best advice for Northern species is to get them in full sun while they break bud and harden off, then move them to dappled shade for the summer and cover the pot with a breathable material when temps get real high. That way they keep compact growth while staying somewhat cooler. I have only done this with spruce so mugo might be different

The more I research and learn about pine bonsai in general, the more I wonder if they are really worth the challenge of getting them to thrive here. The summer heat is definitely the deciding factor. You give good examples of cold hardiness vs heat tolerance too. Another one is the difference in weather here in NC. In Raleigh, where I used to live, their zone is 7b, whereas mine now is 8a. Raleigh gets a bit colder in winter than here in southeast NC, and they often have snow in the winter, compared to VERY rare snowfall where I am now. However, during the summer, Raleigh can regularly have temps in the mid- to upper-90s (Fahrenheit), with occasional 100+ degree days. A few years ago, they had a streak of like 20+ straight days where the high temp was 90 or higher. Here at the coast though, our hottest day this past summer was 87 or 88 degrees, I believe. If we broke 90, it was only one or two days.

Day by day, I lean more towards wanting to spend money on tropical species as opposed to pines to keep me occupied during the winter. At least I can keep those indoors under a grow light during the winter while my deciduous material is dormant. Then they can just go back outside with everything else in April when we've warmed up again.

Hey bucko, why don't you just stay in your lane and spare us all future whining about a tree in mysterious decline?

I dont screw with JPB, olives, trident maple, azalea, etc, so how about you leave the frigid species to those who can unambiguously accommodate them?

Peak millennial. Have your parents ever said no to you?

Fight me.

I'm sorry, that was harsh.

I do want to fight you though.

You talking to me?!?! I'm fully within my rights to investigate your so-called "frigid" species! I'm Gen-X, my friend. No Millennial nonsense here. My parents said "no" to me far more often than I wanted them to.

I will straight up fight you. Meet me on the playground at noon by the monkey bars. Bring your Nerf bat and bring your mommy too, so she can put an ice pack on your bruises!

For the record, it's very likely too hot here for olives, so you can't use that against me. However, I will take my Azaleas and rub them in your face!

 

[sorce]

This truth from another thread is why what @Shibui finds true to be true.

When I do ask for details it often turns out the advice is based on a single bad experience so not really rigorous testing of the theory. Just because something has not worked once does not mean it can never work. Often a minor cahnge to conditions or technique will make a big difference so generalizations are difficult.
Many of the theories I see appear to be based on unsound conclusions.

It's this terribly crippling phenomenon where a newb thinks thing 1 of 85 is not safe because they also did the other 84 at the same time, then remove a good action from the toolkit.

Everything and Nothing is always true.

Deploy.

Sorce

 

[MaciekA]

The more I research and learn about pine bonsai in general, the more I wonder if they are really worth the challenge of getting them to thrive here. The summer heat is definitely the deciding factor. You give good examples of cold hardiness vs heat tolerance too. Another one is the difference in weather here in NC.

This is 100% speculation, but I sometimes think the reputation of pine cultivation difficulty vis a vis climate in various geographic areas of the US is strongly connected to the availability of pumice and the willingness of grower culture within a geographic region to grow pines with a laser focus on transpiration.. In other words, high oxygen, high drainage, inorganic/non-decomposing soil, very strong sun, good air flow, etc. All this, and a respect for the annual lifecycle of a pine, knowing the difference between development and refinement, and understanding how pines build up a battery of energy over time and carefully working with that.

As far as I've seen, pines need sun and heat and that is when the bulk of their growth happens. But many growers seem to ignore that pine roots need to breathe and that seems to be the source of most problems. During this summer's PNW record-setting heat waves, much hotter than NC has ever been, I had some of the most outrageous and frankly amazing growth I've ever seen in my pines, but at no point were any of my pines' root systems a hot persistently soggy mess. I think that's the difference (all other things equal) between trees that thrive through a hot summer (humid or not) and ones that crumple and die.

If the soil conditions resemble a bunch of cool, moist but also airy, structurally-sound caves, a pine will do fine in heat. If the soil conditions resemble a collapsing heat-trapping wet mess of a compost pile, then that pine probably won't be able to transpire well and won't cool itself well, leading to the impression that pines just don't enjoy hot weather. Yet they're all over the southwest and south. Mexico alone has the largest diversity of pines in the world and those mountain sides absolutely roast in the summer.

With respect to your climate, consider that many pine-growing parts of Japan are both brutally hot and brutally humid in the summer and pines are successfully grown there (and that their grower culture reflects lessons learned about what works soil-wise -- it's always airy/porous volcanic particles, even in field growing). Your own neck of the woods, NC, is even home to a JBP-like coastal pine species that does incredibly well with your climate, as long as the soil conditions are correct (i.e. well-draining). Pines do well in hot humid summers as long as they are able to continue to cool themselves with transpiration. This is a fact easily verifiable by looking at Japan, but also growers in your region, some of whom are on this forum. I think you can grow world-class pines in your climate. Your natural environment is doing that already, after all.

 

[leatherback]

You give good examples of cold hardiness vs heat tolerance too.

I think it is important to realize that the USDA hardiness zones are indications of winter cold. It tells you, afaik, nothing about the heat acceptance. It was developed to decide in which areas plants would survive the winter, and is a rough estimate, not taking into account very local microclimatic variations.

 

[AcerAddict]

OK then, to summarize the last few posts, I need to:

1. Quit overthinking it, buy a damn Mugo already, and then see how it goes. (@sorce)
2. Make sure it doesn't overheat and/or drown next summer. (@MaciekA)
3. Use the zones as a guideline, and not an unbreakable rule. (@leatherback)
   
   
   
   
   
   
   
   
4. Fight @A. Gorilla on the playground.

 

[Moridin]

Fwiw my mugo seems to be doing fine in zone 9

 

[Leo in N E Illinois]

OK then, to summarize the last few posts, I need to:

1. Quit overthinking it, buy a damn Mugo already, and then see how it goes. (@sorce)
2. Make sure it doesn't overheat and/or drown next summer. (@MaciekA)
3. Use the zones as a guideline, and not an unbreakable rule. (@leatherback)
   
   
   
   
   
   
   
   
4. Fight @A. Gorilla on the playground.

As @MaciekA mentions, a proper media for pines is crucial to their survival. Roots need to be in good health to survive heat stress and or cold stress depending on your climate.

I live in zone 5b, an area too cold for JBP to reliably survive. Sometimes they make it, sometimes they don't. If I lived anywhere where JBP thrived, like coastal NC, I would grow just about nothing else. You are a fool if you let yourself get distracted from learning how to grow JBP well. It is perfect for your climate, it can do a double flush, meaning rapid development. Damn it man, quit mucking about and get into JBP. There is no pine better documented for bonsai than JBP, your climate is similar to JBP territory in Japan, coastal, subtropical. JBP will even survive a certain amount of salt in the air. So focus on JBP.

Your other NC native pines that you mention, the Loblolly Pinus taeda, and pitch pine, Pinus rigida have somewhat good track record for bonsai. Both have been used with success, in that they have had entries in the Rochester NY, National Show, or specimens at the National Collection in DC. The pond pine, Pinus serotina, is closely related to taeda and rigida, so I would expect similar results from it. Because your growing season is long enough, you should be able to get double flush growth behavior out of all three species. All 3 species are in the Australes sub-section of Pinus, meaning they are fairly closely related. It may be difficult to tell them apart in the field.

Mugo is a single flush pine from high elevation Europe. What does this mean? It means that all the buds that will become the new growth for the year open in a couple weeks. That's it. It is a slow pine to develop. Growth will keep extending for part of the summer, but usually by end of July growth is hardening off. No new buds will pop open July or August. A mugo will require 2 decades to do the amount of growth and ramification you could get out of a JBP in zone 7 in one decade. It develops at half the speed of a JBP. A JBP keeps opening buds all summer long. Mugo can tolerate extreme cold, it normally does not experience extreme heat. Those zone guides are really guess work when it comes to the warm end of the ratings. One problem is that winter might not be cold enough, long enough to release hormone control blocking new buds from sprouting over winter. If you do not get enough "winter chill hours", new buds won't open in spring. So the issue is more the number of hours below 40 F in winter rather than actual high temperatures in summer. This chill requirement is the reason pines are not routinely grown indoors, they can't get the chill they need when inside. But you won't know for certain unless you try. So give one or two a try.

Another NC native pine, Pinus resinosa, the American Red pine, also called Norway pine (even though it is not native to Norway, go figure). Resinosa is technically in the same sub-section of Pinus as mugo and thunbergii (JBP) but resinosa looks pretty different. It has fairly bright reddish, plated bark, long needles and is strictly a FULL SUN pine. It is a pioneer species, colonizing burned areas and sandy areas, it is a tree of the barrens. As bonsai red pine, P. resinosa, is noted for dropping branches as soon as they get a little shade from the branch above. They are difficult to style for bonsai because they don't keep branches. Tall poles, branches only at the very top.

American white pine, Pinus strobus, has been discussed at length here on BNut. Most of us find it difficult to use for bonsai. Pompoms of needles at the ends of long branches, with no back budding. Walk away from it is my advice. I will admit, there is one P. strobus that is outstanding, the tree belongs to Vance Hanna, and has been in training for 40 years. It took at least 20 years before it began to look like anything. Now it is a top ranked tree. So there are exceptions, but generally Eastern White Pine is an exercise in frustration.

So given you are in an area where JBP grow well, you would be foolish to distract yourself with other species of pines when JBP does so well where you live.

 

[AcerAddict]

Wow, thank you VERY much Leo. Great info there. Sincerely appreciated.

I actually got a trio of 2-year-old JBP seedlings last week, so I'm not completely empty-handed when it comes to those. I definitely want some older material though, and I'm still on the lookout for something that checks most of the boxes for me. It's likely I'll plant the seedlings in the ground here on our property and let them grow up for a while.

I have to say that I don't share your passion for JBP. At heart, I'm a maple guy (hence the username), but I do enjoy pines as well, and it would be good for me to know how to work on them. More tools in the toolbox isn't a bad thing. I have a Dwarf Alberta Spruce in addition to the JBP seedlings, but that's where my pine collection ends.

 

[Adair M]

Wow, thank you VERY much Leo. Great info there. Sincerely appreciated.

I actually got a trio of 2-year-old JBP seedlings last week, so I'm not completely empty-handed when it comes to those. I definitely want some older material though, and I'm still on the lookout for something that checks most of the boxes for me. It's likely I'll plant the seedlings in the ground here on our property and let them grow up for a while.

I have to say that I don't share your passion for JBP. At heart, I'm a maple guy (hence the username), but I do enjoy pines as well, and it would be good for me to know how to work on them. More tools in the toolbox isn't a bad thing. I have a Dwarf Alberta Spruce in addition to the JBP seedlings, but that's where my pine collection ends.

I second Leo’s advice.

Dwarf Alberta Spruce are not very adaptable for bonsai culture. And they are not a “pine”.

Look, if you seriously want to learn about JBP, working with a 2 year old seedling won’t teach you anything. It needs about a decade to grow a trunk and a few branches. Spend a couple hundred dollars and get a nice starter JBP that has a decent trunk, and where you can learn to wire the branches, learn how to set pads, and begin ramification by decandling, and balancing by learning about needle pulling. That’s the fun part! Not sitting around for ten years waiting for a trunk to develop!

Mugo are MOUNTAIN trees. So are Scots pines. You live in a COASTAL region. JBP are coastal trees. See where I’m going?

There’s a lot of posts about Mugo on this forum because they’re cheap. Problem is, the nursery Mugo have been pruned to make shrubbery! You will spend years trying to convert it back from a shrub form into a tree form.

Your time would be far better spent using a JBP raised by someone who grew it intending for it to be a bonsai. Yes, it will cost more. But it’s worth it because you will have more fun with it! And learn all those things I mentioned before: wiring, decandling, etc.

 

[AcerAddict]

Dwarf Alberta Spruce are not very adaptable for bonsai culture. And they are not a “pine”.

It was an impulse buy at Lowe's because it was just $12. I plan to use it for wiring practice. I meant to say where my "conifer" collection ends, but couldn't edit the post. Obviously a spruce it not a pine. It's a spruce!

Look, if you seriously want to learn about JBP, working with a 2 year old seedling won’t teach you anything. It needs about a decade to grow a trunk and a few branches.

Agreed, which is exactly why I said "It's likely I'll plant the seedlings in the ground here on our property and let them grow up for a while."

Spend a couple hundred dollars and get a nice starter JBP that has a decent trunk, and where you can learn to wire the branches, learn how to set pads, and begin ramification by decandling, and balancing by learning about needle pulling. That’s the fun part! Not sitting around for ten years waiting for a trunk to develop!

I've been searching for exactly that type of material, believe me. Every week, I'm glued to the bonsai auction/sales groups on Facebook, and visiting every retailer website I can think of to see if there's anything new available. Like I said before though, I'm a maple guy before anything else. It really put a dent in the pine budget when I spent $350 on a new maple and $200 on a new elm just in the last three weeks. Plus, when I sift through the auction and retailer sites looking for suitable JBP material, I'll see a Zelkova that catches my eye, or a Hornbeam, or a Cryptomeria, or a Cypress, or a...see what I mean? Pines are simply low on my list of material priorities. Not sure if you're a gun guy or not, but it's often said that every gun owner needs to have a 1911 in their collection. It's a timeless classic that's been popular for over 100 years. I have a 1911 that I'm in love with, and I can't imagine not having it now. In similar fashion, I feel like I need to have a quality JBP in my collection because it's the quintessential pine for bonsai, but I guess right now I'm not sure if I actually want a nice pine before I obtain some of these other trees I've mentioned.

Mugo are MOUNTAIN trees. So are Scots pines. You live in a COASTAL region. JBP are coastal trees. See where I’m going?

I do, yes. This thread has without a doubt cleared that up for me.

 

[A. Gorilla]

FWIW, a bonsai teacher of mine had a bomber formal upright DAS which put to rest any doubt about their suitability.

He gave it what it wanted and it was TIGHT... TIGHT-TIGHT.

 

[MaciekA]

I have a Dwarf Alberta Spruce in addition to the JBP seedlings, but that's where my pine collection ends.

Interesting that you mention DAS in the context of this thread -- I've personally found that spruce, specifically alberta spruce in my case, is one of the only species in my garden that gets properly stressed by the oven-dry heat / sun of PNW summers, and requires a lot more work (rotation / cooling / shading on severe heatwave days) to protect from foliage damage in the hours/days after peak heat. They can definitely live on the coast and in the mountains, but valley climates are a bit of a challenge. Heat waves eviscerate the canopies of suburban landscape alberta spruce in my neighborhood. Those do fine, but they're big beefy landscape trees.

I agree with @Leo in N E Illinois 's characterization of JBP. It is a sublime species and because it is so well documented, with so many mentors to turn to for advice, you will develop an excellent mental model for the species pretty fast. I think if one knows how to grow JBP very well, then other pines and eventually other conifers become easier to reason about over time.