Autumn Repotting

Hi everybody,

I have a question about collecting and repotting in the fall. I have a japanese garden juniper, mugo pine, and a cotoneaster all still in nursery soil that i have picked up over the summer. I would like to get them out of that soil and into a bonsai soil if i could, but its not a big deal if its too late i will just wait until next spring. Also I have found a few american larch that i would like to collect. I just wanted to know what everyone would recommend before i take any action. The temperature here is on average about 15C and it is fairly wet most of the time. Thanks for any suggestions

Hello,
In spring, the days are longer, the light is strong, the roots grow, photosynthesis is working , the sap is flowing and going up , the temperature is high.
In autumn, the days are short, the light is low, photosynthesis is low, the sap down, the roots are growing, but a little, the temperature drops, find the solution !!!!.
That's not so easy, but for a lot of species, repotting in spring is better.

Collecting or repotting in the fall works in the southern latitudes, where there is enough time for roots to grow. It is not recommended in the North. Bite the bullet & wait till spring.
Iris

Amen.

Unless you have a Hothouse.

Love and light

I'd like suggest that actually you've got two questions - IMHO= Re-potting and collection can be two very different functions and will depend on objectives, vigor/health of stock, location, one's expertise, the species, stage in development.... etc.

For re-potting for most trees which usually involves some root work - wait and do it in the spring (there are exceptions to this too), however if you need to you can slip pot trees in late summer early fall - moving from the ground into a grow box/pot or from one pot to a much larger pot with no or very little root pruning/work.

Collecting- From my knowledge, experience and in our area (50th parallel) roots are still active this time of year (late summer) -and most of our collecting is done from the middle of August to October with great results.  I've collected for the last 4 years during that period and have had some great success.

I would think that your winters are significantly colder compared to ours (out here on the wet coast) so you would probably experience much colder weather earlier so you could try it now (if you have read all you can about collecting) and utilize some good winter protection techniques.    
Good Luck.
Cheers Graham

Thanks for the great responses everyone. Maybe i will collect just one of the larch this season and see how it does. Other than that i will leave everything else until the spring no need to rush, its all a waiting game anyways.

Wait until Spring-Larch are notoriously difficult to re-establish after collection,sometime,s dying 2-3 years after collecting with the best after care.Spring give,s you the best chance of survival.Don,t collect after the bud,s have started to turn green,when they,re a reddish colour is the best time.

The mighty Nick Lenz himself recommends autumn collection for bog dwelling tamarack. I, too, have collected this species in the fall with encouraging results. However, if you have not done so already, your autumn will be far better spent finding a copy of his book and reading the chapter on larch twenty or thirty times before slipping on the Wellies come the spring.