Deciduous Air Layerings class of 2018
Posted: December 30th, 2018, 9:04 pm
First off i'm sorry for the flipped photo, no matter what i do it just won't orient correctly.
This year i have been working on prop of some of my uncommon and rarer varieties of Japanese Maple, along with a handful of other deciduous species. Being that Japanese Maple cuttings from cultivars have extremely low success, i use air layering on them to take sections or remove them from unsightly grafts.
I thought i might jot down a few thoughts on the various species and their reactions to air layering for successes and failures now that all those that have grown roots have been separated for the year.
Successes
Acer palmatum (straight species)
Dead easy almost foolproof. Nothing really to add on that, just set the layer and wait. Takes 4-5 weeks from initial ringbark to roots emerging like clockwork.
Acer palmatum 'Kamagata' (front right) -
I had great success with this cultivar. Really nice radial roots emerged quickly and it held it's visual appearance well as compared to other species i tried. Leaf size is naturally small and from all accounts provides strong and reliable autumn hues of orange both of which are pluses for bonsai.
Acer palmatum 'Shindeshojo' (Far left behind purple leaves of prunus)
An unpredictable species from my experience with success only on one of two attempts despite them being similar thickness and set at the same time. Last year i also air layered this variety and had even less success with it but i was determined to persevere owing to it's beautiful spring foliage colour. I put last year's one in the ground, but it struggled so it went back into sphagnum moss and it has perked up again.
Clear loss of colour and visible health of leaves on the air-layered branch compared to the untouched branches. Will see if it recovers strength after being separated or if it continues to struggle on its own roots.
Acer palmatum 'Arakawa' (Centre leaning over straight species)
I set two air layers on two separate trees. One reluctantly grew roots, the other firmly refused to. I'm certain this is more to do with me trying to use a branch that was too thin rather than a propensity for this variety not to air layer well. Leaf size is rather large and coarse so this cultivar would be best for a larger tree certainly.
Just like Shindeshojo it also clearly lost visible colour/strength in the leaves on the air layered section, however it has been quite happy since being separated from the parent tree. I will grow on my motherstock trees for a few years untouched to get thicker branches that may layer more successfully in future.
Acer palmatum 'Shishigashira' (two dark green leaved rear left and right)
I have several motherstock trees of this cultivar, one for more advanced than the other, so i set 3 layers on that one and one on the other. Two from the large tree were successful, one failed to separate but the branches have not died off entirely and the one on the younger tree started to put a root out then stopped so i will try them again next year.
Of the two that were successful; one (the single trunk) grew incredible roots very quickly so i suspect i hit a dormant bud or node with my layer, the other started more slowly and had only grown roots on one side (albeit strong roots) when i separated it. Both performed well during the layering, no visible loss of strength and were quite content even in a very sunny position.
Prunus cerasifera 'Oakville Crimson Spire' (purple leaves at the front)
More out of horticultural curiosity than anything else i tried airlayering this prunus as my attempts on several cherry blossoms had failed dismally and i was wondering if it was me or the entirety of the prunus species. Turns out it was just me! Both rampantly grew roots and never looked back. Separated from the host plant very quickly and have already filled the pots with roots.
How this variety will go for bonsai i don't know as it is a fastigiate/ semi fastigiate variety so getting it to spread out and have any movement at all will be a wiring job.
Failures
Acer palmatum 'Mikawa Yatsubusa'
This variety just does not want to air layer for me. I tried last year and got nothing. I tried again this year and it looked like i might get one to start rooting but it too did not come to fruition. I'm giving up on this variety for air layering as I've had no luck with 6 or more attempts to even get so much as single root to emerge.
Acer palmatum ' otohime'
I attempted this variety but i think the branch was too thin and the whole branch died off. Might look into it again in the future as the leaf size is very small though it is a spreading dwarf variety so keeping a tall apex alive would be challenging
'Tilia cordata' Little Leaf Linden
I couldn't find any information on if this species took to air layering so i just tried it. The answer was no in my case, or at least not in a single season. I also tried cuttings but they also do not root. Unsure if i will try again or not.
Prunus shirotae 'Mt Fuji' and an unknown cultivar of same (flowering cherry/sakura)
No luck with either of these with multiple air layerings, wounds just leaked sap and went funny.
Prunus elvins
Also a fail on this prunus, the wound looked like it was ready to push roots out but nothing ever happened. It's a shame as it has a very nice flower and i was hoping to get some extras to work with.
lagerstroemia indica Crepe Myrtle
I set two air layers on a large tree in the garden, i suspect i set them too late rather than it being a species that doesn't want to air layer. That and it's a hot part of the garden and the moss can dry out easily there which wouldn't help. Will try again next year.
Final thoughts
1. Liquid rooting hormone is far more successful than powder from my fairly unskilled approach of 'if i set many i should at least get one'.
2. Start in spring and don't be tempted to keep going into summer. My air layers started earlier have far better results than later ones, many of which never even grew roots
3. Stop propagating so much young material that i fill up every corner of my house with it and get back to bonsai proper.
For Japanese Maple go for a branch that is an absolute minimum of pencil thickness to have any chance of success. I've had good success up to thumb thickness which is the thickest I've attempted so far. Thicker actually works far better and more quickly. 4-5 weeks seems to be the time-frame to see roots emerging in generally speaking though, as i mentioned above, some seem far more reluctant than others to root.
Anyone with more experience than i than can chip i feel free
This year i have been working on prop of some of my uncommon and rarer varieties of Japanese Maple, along with a handful of other deciduous species. Being that Japanese Maple cuttings from cultivars have extremely low success, i use air layering on them to take sections or remove them from unsightly grafts.
I thought i might jot down a few thoughts on the various species and their reactions to air layering for successes and failures now that all those that have grown roots have been separated for the year.
Successes
Acer palmatum (straight species)
Dead easy almost foolproof. Nothing really to add on that, just set the layer and wait. Takes 4-5 weeks from initial ringbark to roots emerging like clockwork.
Acer palmatum 'Kamagata' (front right) -
I had great success with this cultivar. Really nice radial roots emerged quickly and it held it's visual appearance well as compared to other species i tried. Leaf size is naturally small and from all accounts provides strong and reliable autumn hues of orange both of which are pluses for bonsai.
Acer palmatum 'Shindeshojo' (Far left behind purple leaves of prunus)
An unpredictable species from my experience with success only on one of two attempts despite them being similar thickness and set at the same time. Last year i also air layered this variety and had even less success with it but i was determined to persevere owing to it's beautiful spring foliage colour. I put last year's one in the ground, but it struggled so it went back into sphagnum moss and it has perked up again.
Clear loss of colour and visible health of leaves on the air-layered branch compared to the untouched branches. Will see if it recovers strength after being separated or if it continues to struggle on its own roots.
Acer palmatum 'Arakawa' (Centre leaning over straight species)
I set two air layers on two separate trees. One reluctantly grew roots, the other firmly refused to. I'm certain this is more to do with me trying to use a branch that was too thin rather than a propensity for this variety not to air layer well. Leaf size is rather large and coarse so this cultivar would be best for a larger tree certainly.
Just like Shindeshojo it also clearly lost visible colour/strength in the leaves on the air layered section, however it has been quite happy since being separated from the parent tree. I will grow on my motherstock trees for a few years untouched to get thicker branches that may layer more successfully in future.
Acer palmatum 'Shishigashira' (two dark green leaved rear left and right)
I have several motherstock trees of this cultivar, one for more advanced than the other, so i set 3 layers on that one and one on the other. Two from the large tree were successful, one failed to separate but the branches have not died off entirely and the one on the younger tree started to put a root out then stopped so i will try them again next year.
Of the two that were successful; one (the single trunk) grew incredible roots very quickly so i suspect i hit a dormant bud or node with my layer, the other started more slowly and had only grown roots on one side (albeit strong roots) when i separated it. Both performed well during the layering, no visible loss of strength and were quite content even in a very sunny position.
Prunus cerasifera 'Oakville Crimson Spire' (purple leaves at the front)
More out of horticultural curiosity than anything else i tried airlayering this prunus as my attempts on several cherry blossoms had failed dismally and i was wondering if it was me or the entirety of the prunus species. Turns out it was just me! Both rampantly grew roots and never looked back. Separated from the host plant very quickly and have already filled the pots with roots.
How this variety will go for bonsai i don't know as it is a fastigiate/ semi fastigiate variety so getting it to spread out and have any movement at all will be a wiring job.
Failures
Acer palmatum 'Mikawa Yatsubusa'
This variety just does not want to air layer for me. I tried last year and got nothing. I tried again this year and it looked like i might get one to start rooting but it too did not come to fruition. I'm giving up on this variety for air layering as I've had no luck with 6 or more attempts to even get so much as single root to emerge.
Acer palmatum ' otohime'
I attempted this variety but i think the branch was too thin and the whole branch died off. Might look into it again in the future as the leaf size is very small though it is a spreading dwarf variety so keeping a tall apex alive would be challenging
'Tilia cordata' Little Leaf Linden
I couldn't find any information on if this species took to air layering so i just tried it. The answer was no in my case, or at least not in a single season. I also tried cuttings but they also do not root. Unsure if i will try again or not.
Prunus shirotae 'Mt Fuji' and an unknown cultivar of same (flowering cherry/sakura)
No luck with either of these with multiple air layerings, wounds just leaked sap and went funny.
Prunus elvins
Also a fail on this prunus, the wound looked like it was ready to push roots out but nothing ever happened. It's a shame as it has a very nice flower and i was hoping to get some extras to work with.
lagerstroemia indica Crepe Myrtle
I set two air layers on a large tree in the garden, i suspect i set them too late rather than it being a species that doesn't want to air layer. That and it's a hot part of the garden and the moss can dry out easily there which wouldn't help. Will try again next year.
Final thoughts
1. Liquid rooting hormone is far more successful than powder from my fairly unskilled approach of 'if i set many i should at least get one'.
2. Start in spring and don't be tempted to keep going into summer. My air layers started earlier have far better results than later ones, many of which never even grew roots
3. Stop propagating so much young material that i fill up every corner of my house with it and get back to bonsai proper.
For Japanese Maple go for a branch that is an absolute minimum of pencil thickness to have any chance of success. I've had good success up to thumb thickness which is the thickest I've attempted so far. Thicker actually works far better and more quickly. 4-5 weeks seems to be the time-frame to see roots emerging in generally speaking though, as i mentioned above, some seem far more reluctant than others to root.
Anyone with more experience than i than can chip i feel free