Hope you are all doing well and your repotting season has been succesful. Mine is almost over but ive got one or two trees i might not get to.
So thats why i am coming to you for advice and experiences.
Its about a picea abies repotting. I read an article in Bonsai Art that should a summer repot of a picea. I think it was Harry Harrington who wrote the article in the UK. It maintaned that picea could be repotted in summer because they grow a lot of roots then (or at least thats what i think it said…)
Any of you got any experience with picea summer repotting?
I occasionally repoted conifers in August. The trees had no problem with that and recovered very well. Of course you should place them in the shade after repotting for a few weeks.
Walter Pall was also repotting Picea when I visited him in his garden in August. He’s got the best Picea Bonsai I know and quite a lot of them too. So I’m pretty shure he knows what he’s doing.
I am almost done repotting, with a couple of trees to get to. I got a lot more trees done than last year, so that’s progress, but there’s still room for improvement. I must be part reptile since I never get active until it gets nice and warm. It’s really hard to be motivated when it’s cold and wet outside.
I’m kind of pushing the boundary with some of my trees, as in repotting pines when they have already pushed candles.
Regarding Picea, as I recall, Walter Pall lives in Germany. I have spent quite a bit of time there myself and know that it is around the latitude of Maine. In August, the days are already getting much shorter and the weather is cooling off and plants are beginning to think about dormancy. It’s probably enough time for the repotted Picea to develop some new roots before the winter comes. I could never try it here in Northern California since things can still get burnt to a crisp in a heart beat. Walter’s location probably has a lot to do with his success, as well as his expertise of course.
You are right, Munich is about the same latitude as Maine and yes, in August days are already getting shorter. BUT: August is still the hottest month in Germany with temperatures up to 40°C in some of the recent years (that’s above 100°F). With all I know about plant physiology this may even be the reason why you can easily repot at this time of year because at temperatures above 35°C plants stop transpiration. As long as you provide shade for those trees and closely monitor their watering needs they should be fine.
Btw, I think the reason why Walter grows such good Picea is because he lives in the very south of Germany close to the alps and at a higher altitude. It’s a little cooler there and also it rains a little more. Picea are native to cooler mountain regions and need that kind of climate. I have a south-facing balcony in the 4th floor in Berlin and Picea hardly survive there. Japanese Maples burn crispy within one year at my place - Walters Japanese Maples are thriving beautifully. People often talk about the climate differences in different parts of the world but the microclimate of your garden / balcony can differ greatly even within the same city. I think that should be taken into consideration a lot more.
I also have a south facing garden and live rpughly 1 hour from the alps. I still get hot summers up to 35 celsius and more and more very dry summers…
Microclimates even in my own garden are fascinating. Depending on shade, wind exposure, sunshine and proximity to the house there are massive differences.
I am definitely going to give the summer repot a shot as the buds are open now and are pushing length… so too late there…
Would you consider doing other work now like branch removal before a repot in summer or just let it gain strength till then?
Hmm, good question. Maybe it could be even helpful to remove branches as this reduces the trees need for water. But this is sheer guessing, not knowledge.
If you do any large-ish limb cutting, be shure to use the liquid (latex -like) tube cutpast. You WILL get a small sap bubble under it, but, it will minimilize drip and moisture loss.
K