Spruce heat tolerance

[Kodama]

Hello BNuts... having troubles with spruce. The birds nest spruce didn't make it through winter. The two Alberta's are suffering same die back. I realize this starting occurring in the fall. While all were well watered the summer/fall of last year was hotter than usual with hot dry winds.

I think the roots got way too hot even though I maintained water and didn't let dry out. Are spruce more sensitive to heat? Maybe I should shelter during hot spells. Hmmmm.

 

[Scorpius]

I'm in northern Indiana and Alberta Spruces do terrible in my area. They hate the dry humid summers I have. Blue spruces grow well in our area and I've had no problem growing them in pots.

I have a real nice ezo spruce for its first summer with me and I'll definitely be giving it afternoon shade once July hits.

 

[Colorado]

Spruce can definitely be sensitive to heat. I usually provide a bit of protection from the hottest sun in the summer.

 

[Tieball]

Alberta Spruce bonsai tree….I’ve only had one….died after the first winter. Maybe they do better growing in the wild. The tree did not grow for me. I just moved on to other tree species and didn’t look at another Alberta Spruce.

 

[Shogun610]

Well first share what your order of operations were.. what would be your process / timeline for how long you’ve had this tree(s) and what was down to it leading up to its death/ decline.

 

[Kodama]

I appreciate the thoughts. Had the bird nest 2 years. Repotted it from nursery can last year early spring. Chopped 1/3 roots and 1/2 bare root around the edges and potted into 1:1:1 APL and some bark. I kept the core soil with plan to change that the following year. Seemed to grow fine as I did shelter for two weeks before moving to full sun.

Perhaps I should have put some organic soil in the mix to help retain moisture. I did notice that pot seemed to retain alot of heat in the summer.

The decline was starting to be noticed in early winter and thought maybe it was the cold snap we had last year but trees were tucked away under mulch bed and protected from the wind.

That's why I think it was the brutal heat and dry winds as the Alberta's were not repotted but all were not sheltered during summer / autumn heat.

 

[Shogun610]

I appreciate the thoughts. Had the bird nest 2 years. Repotted it from nursery can last year early spring. Chopped 1/3 roots and 1/2 bare root around the edges and potted into 1:1:1 APL and some bark. I kept the core soil with plan to change that the following year. Seemed to grow fine as I did shelter for two weeks before moving to full sun.

Perhaps I should have put some organic soil in the mix to help retain moisture. I did notice that pot seemed to retain alot of heat in the summer.

The decline was starting to be noticed in early winter and thought maybe it was the cold snap we had last year but trees were tucked away under mulch bed and protected from the wind.

That's why I think it was the brutal heat and dry winds as the Alberta's were not repotted but all were not sheltered during summer / autumn heat.

hmm okay your root work seems to be standard nothing sticks out for that.
I use a lot of akadama and pumice , maybe some lava for spruce as they do like water retention and that’s where the akadama comes into play with water retention. I do not like bark, it clogs up the water drainage , and does not allow enough oxygen into the mix.. I think you may want to look into your soil mix in future. Also I put spruce in shade on really hot days but I know Colorado blue spruce is more sun tolerant than other spruce types.

 

[Kodama]

Thanks all...I do have a Colorado Blue and a few Junipers and yeah those did just fine. If I try those again I'll plan on keeping them cool.

 

[Tieball]

I use bark in my substrate mix. Bark is a natural ingredient in the soil around me. This is about the first 7-8” of soil. After that layer I have beach sand and fast drainage.

 

[GGB]

I wrap old, light colored t-shirts around my spruce pot when it’s above 88F. This year it will actually be going under shade netting around June 15th. Mine definitely hates the heat, it’s p. englemann

 

[Natty Bumppo]

Not really bonsai related, but I remain surprised at how garden centers around here (central Missouri) sell so much blue spruce, Alberta spruce and white cedar. Nearly all will die. Summers just too hot and dry around here for those species. But folks still buy them.

 

[Natty Bumppo]

Not really bonsai related, but I remain surprised at how garden centers around here (central Missouri) sell so much blue spruce, Alberta spruce and white cedar. Nearly all will die. Summers just too hot and dry around here for those species. But folks still buy them.

 

[James W.]

We are hotter and dryer and I have done fine with the spruce I have tried.
I keep the pots on the ground or on a layer of mulch
I cover the pots in mulch
They are in full sun until about 6:00 in the evening
When I water them I hit the foliage with water to discourage spider mites (especially DAS)
I have killed my share of spruce, but not with the heat or cold.
My observation is that spruce take a long time to let you know you killed them, what you did could have been a year ago. This makes it a challenge sometimes to figure out what went wrong.