Too late to pot cotoneaster?

[Dan Brown]

Howdy all. I just picked up a nice thyme leaved cotoneaster. I live in zone 6, do you think it is too late in the year to put this plant in a bonsai pot?
Thanks,
Dan

 

[LanceMac10]

Did you get this at Bonsai West this past weekend?

It's late to do root work, but perhaps you could up-pot it without messing with the roots too much.
I would leave it be until early spring '18.....

 

[GrimLore]

I live in zone 6, do you think it is too late in the year to put this plant in a bonsai pot?

I have killed a few working on them this late in the year. Recently picked up a Cranberry Cotoneaster and it will stay in the Nursery container until late March. Way it works here in 6b - 7.

Welcome to B-nut!

Grimmy

 

[Dan Brown]

Did you get this at Bonsai West this past weekend?

It's late to do root work, but perhaps you could up-pot it without messing with the roots too much.
I would leave it be until early spring '18.....

Yes I did get it at Bonsai West just yesterday. I will take your advice and wait till next spring.
I'm in Hudson btw.
Dan

 

[Dan Brown]

I have killed a few working on them this late in the year. Recently picked up a Cranberry Cotoneaster and it will stay in the Nursery container until late March. Way it works here in 6b - 7.

Welcome to B-nut!

Grimmy

Thanks.
Dan

 

[0soyoung]

Howdy all. I just picked up a nice thyme leaved cotoneaster. I live in zone 6, do you think it is too late in the year to put this plant in a bonsai pot?

They can be repotted sometime around August, if you want, but not now.

I realize this will likely be the hottest time of the year, but it is actually a good thing as long as temperatures are generally below 95F. Plant metabolism increases with temperature (up to this approximate limit). Roots need to be somewhat cooler for optimal growth. (around 70F is optimuml get a cheap meat thermometer and stick it in the soil among the roots - shading the pot will generally make this possible).
If the relative humidity in your area is low then, you may need to keep it in shade for about 10 days after potting if the relative humidity is low. Throughout most of the western U.S., August is a rainy season with higher relative humidity. You won't have any problems if rH is about 50% or more (my location). However, a BNutter in New Mexico showed us successful collecting and potting a native oak in rH < 15%. I am still surprised that it did not require a humidity tent.

 

[LanceMac10]

@Dan Brown is in the next town over from me.....and Dan, we are definitely NOT zone 6!!!
I'm not sure we are even zone 5 anymore!?!?
Any fall repotting will need the requisite winter care, not all that easy or convenient around here.

 

[Lazylightningny]

You can take a little soil off the top to expose the nebari, but I'd probably leave it until next spring. Keep the soil moist and fertilize it.

 

[0soyoung]

Any fall repotting will need the requisite winter care, not all that easy or convenient around here.

So what happened when you repotted around August?

Most of hardening for winter comes from light, but deepening overnight frosts. Sudden changes from 50 degrees to 10 degrees will kill just about everything (with a low thermal mass). Historically the average first freeze date in Nashua is at the end of September. So make 'around' mean the last week of July and there is two months of frost-free weather after repotting - 6 weeks should easily be adequate.

 

[LanceMac10]

So your saying repot in the hottest time of the year here?

 

[0soyoung]

So your saying repot in the hottest time of the year here?

Yes

I realize this will likely be the hottest time of the year, but it is actually a good thing as long as temperatures are generally below 95F. Plant metabolism increases with temperature (up to this approximate limit).

I see that it very rarely gets to 90F there, so no worries unless the air is extremely dry.

 

[GrimLore]

I see that it very rarely gets to 90F there, so no worries unless the air is extremely dry.

Here that applies to Spruce,Cedars, Bald Cypress, ALL Tropicals, Cacti, and Succulents. Pretty much everything else won't make it through Winter concerning outdoor plants... Perhaps it is an altitude difference but I know my growing in this location.
Other plants "can" be if needed but require special care.

Grimmy

 

[AlainK]

I don't know about 'thymifolius', but I've often repotted cotoneaster horizontalis in June-beginning of July without any pb.

Later, it can be an issue because the new roots are fragile and can suffer from winter frosts.

 

[augustine]

Some say cotoneasters are "bulletproof" but I think they warrant a bit of caution. They are a bit touchy about root pruning. Don't massacre the root ball when you do the work next spring.

Some varieties are more touchy than others according to a bonsai stock nurseryman I spoke with. I don't know about the thyme leaf variety. Good luck.

 

[Underdog]

I killed a Tom Thumb dwarf variety last year being too aggressive. His replacement is still in the nursery pot after only mild root raking and sitting back in the original can on a layer of lava to improve drainage. I cutback and wired in fall. Survived winter anyway. Love to get him in a smaller pot w/better soil but he's growing like a weed in the big ugly can.
I think both are posted in the Cotoneaster are Fun thread.
Watching this thread. Good luck w/yours.

 

[AlainK]

I've often repotted cotoneaster horizontalis in June-beginning of July without any pb.

An example: two of the five that I repotted 3 weeks ago, in early July. They didn't lose a single leaf, on the contrary they have new light green leaves. The soil is mainly compost, plus some sand and pozzolane. The pot in the middle is what they had stayed in for several years, so the roots were coming out of the holes at the bottom and I had to prune between 1/2 and 1/3rd of them. The one on the right has a nice movement, I'll see later what I keep at the top. The one on the left could be a future "broom" :



I will overwinter them in a box full of pine bark and/or hemp straw to protect the roots from the frost :

They are a bit touchy about root pruning.

I think the main thing is that new roots are very sensitive to frost, so after repotting, it's better to give them a proper shelter. I had a big one, the base as thick as my wrist, and when I removed it from the ground and potted it, I removed at least 75% of the roots. It lived happily for four years until a summer that was particularly hot and I left it in full sun while I was away : it never recovered.

 

[AlainK]

Update. I kept them in a tray with tap water during the heat wave, you can see from the white line on the bottom of the pots how hard the water is here. :