Colorado Blue Spruce

When I first started growing bonsai some 20 years ago, the experts looked down their nose at this species. It was only used as a practice specimen for isolated beginners who couldn't get hold of anything better. Now they seem to be more popular. The convention in Denver is offering three workshops in them, selected yamadori at fancy prices, and pre-trained nursery trees for shohin. I know they want to showcase native trees, but still... Has there been a change in attitude toward Picea pungens?
Iris

I am new but I think people are more open minded now. They are willing to experiment and try native plants hardly used in bonsai before. Some work some don't...and maybe this spruce is one of those that works.

I believe having the open mind support from well known bonsai figure (like Walter Pall) opened the gates for other species. JMHO

I won't have one till June, but can anyone recommend a good solid article on the care of this species? I imagine it is little known in Europe, except perhaps by Walter Pall.
Iris

It is well known in Europe as many gardens have one. It is called "blue fir tree" and does well in central and northern European climate. The nursery trees very rarely are useful for bonsai though. We treat them just like our European spruce (Picea abies) of which we have tens of thousands as bonsai.

Thanks, but I could use more information. The only time I tried Picea abies (we call it Norway spruce) as bonsai, they died.
Iris

European spruce: well draining substrate with 20 % either rough peat, bark particles, every day lots of water, on hot days more than once a day, lots of feed about every ten days to two weeks, full sunshine in moderate climate, semi-shade in hot regions, overwinterning OUTSIDE - not in greenhouse, after repotting leave alone un tuoched for more than one year. Do styling step wise.
I suggest the same for Colorado blue spruce.

Walter:
With spruce;

After styling (wiring) in autumn should we wait a year and not repot and root prune the following spring?

If not can we gently slip pot upwards in spring if the tree is currently pot bound and having drainage issues?

-Jay

Jay,

Only one major insult per vegetation period. A major insult is repotting or serious styling.
Note that I clearly say 'vegetation period'. It is a common mistake to think that six months in between doing something seriously to a tree is fine. It depends on when these six months happen. Styling in fall and repotting in spring: what do you think happens over winter in six months? The answer is: 'almost nothing'. This measn it is the same as thinking you can style in spring and repot three weeks later. If you styled in spring and ask me whether you can repot in fall I would say ' well, if you can avoid it, don't do it, but you can do it with some risk involved.' The difference is that the tree had almost a full vegetation period to overcome the insult.
Slip potting by not doing anything to the rootball you can always do - any time, if you have a firm root ball. Often collected trees don't have a firm root ball for many years.

Thank you for the clarification, and advice Walter, Indeed it makes perfect sense.

I will merely slip pot it up in spring.
Best
-Jay

Thanks, Walter. So if I style it at a workshop in June, it gets repotted the following spring. I don't have a greenhouse. Most of my hardy bonsai are wintered in a sunporch, with wildly fluctuating temperatures between low thirties (around 0 C) to mid-forties (around 5 C). For winter I keep my American larch in the ground with a rose cone over it. I gather you suggest the same for the blue spruce.
Iris

You know Iris

My experience echos something else Walter recommends in that the one year I wintered my Spruce in an unheated green house the tree suffered. I wont do that again. The warm air temp on sunny days and the persistent frozen root zone lead to a lot of burned needles.

-Jay

Spruce have the habit to let die all tiny roots in winter. They bet on rain, fog, mist, general high humidity to get enough moisture for the tree over winter. They also bet on the tree just freezing stiff and waking up a couple of months later, not needing any fine roots anyway. In spring then the fine roots come back.
In a greenhouse environment the tree has big problems over winter. It is not humid, dry instead, the tree dries out much more then the rest. In spring the foliage, if still alive is very weak.
It is much better to leave the tree outside. It will not be hurt by freezing for a few months or by being buried under snow for a long time.
Or you mist the tree eery day in the greenhouse.

Walter Pall wrote:Spruce have the habit to let die all tiny roots in winter. They bet on rain, fog, mist, general high humidity to get enough moisture for the tree over winter. They also bet on the tree just freezing stiff and waking up a couple of months later, not needing any fine roots anyway. In spring then the fine roots come back.

Walter,
Thats fascinating;
I certainly never knew of that trait, yet it explains a lot of what have seen with regards to my Spruce in winter storage.

Are there other evergreen species that also do this in winter?
-Jay

Jay,

I don't know for sure about other families. This shold be researched really.

Walter Pall wrote:Jay,

Only one major insult per vegetation period. A major insult is repotting or serious styling.
Note that I clearly say 'vegetation period'. It is a common mistake to think that six months in between doing something seriously to a tree is fine. It depends on when these six months happen. Styling in fall and repotting in spring: what do you think happens over winter in six months? The answer is: 'almost nothing'. This measn it is the same as thinking you can style in spring and repot three weeks later. If you styled in spring and ask me whether you can repot in fall I would say ' well, if you can avoid it, don't do it, but you can do it with some risk involved.' The difference is that the tree had almost a full vegetation period to overcome the insult.
Slip potting by not doing anything to the rootball you can always do - any time, if you have a firm root ball. Often collected trees don't have a firm root ball for many years.

Best tip/guideline I've read so far. I am filing this info for future reference. Thanks Walter!!!

Here I am in Colorado, visiting relatives after the convention. My souvenir is a tiny 8-inch (20 cm) shohin spruce. I can't take credit for the work, because Lindsey Bebb wired the trunk for me. Mrs. Bebb wired all the branches because the room was too dark for me to see. I take credit for keeping the jin, without which I think it would be just a stick in a pot. Photos when I get home.
I didn't find as much information online as I thought I would. One tip, supposedly from Ryan Neil, is to let the shoots extend in the spring, then cut them back. This promotes back-budding.
Vendor room was better than I expected. I bought a pinch pot for my new tree from a lady from San Diego, but it may take two years for it to fit.
I am still not sure how much root pruning this tree will take, especially for its first potting.
I would be afraid to winter such a tiny specimen outdoors. I think it should do all right in the sunporch, which does not dry out that much. It is not a greenhouse.
It was interesting to see the native spruces & other conifers along Interstate 70 (main east-west highway across Colorado). The higher up they are (to 12,000 feet, the treeline), the skinnier they grow. Down around 10,000 feet, they are more pyramid shape. The end of June, there are patches of snow on the higher mountains. Funny, some of the Rockies remind me of their cousins in Ecuador.
Iris

Hi Iris,

There's a very good page of explanation on Harry Harrington's website.. It's about picea in general but the example photos are taken from a Picea pungens 'Glauca'.

I tried his advice on one of mine, and it worked well.

All of my bonsai are flourishing, deciduous and conifer alike and yes, they all abide in a greenhouse. High desert is often brutal, intense heat, sun, wind, fluctuating winter temps. This spring a Yamadori Colorado Spruce has joined the rank and file. I have good ventilation, a swamp cooler and heater (with thermostats), timer misting system, and my constant tending. So far, so good. The only bugs have been attracted solely to my wife's miniature roses, which I quarantined and sprayed and then searched every nook and cranny for the littlest signs for days. Am I happy with the greenhouse? Yep. Will I ever build another? Nope. Oh, and my spruce looks awesome...