Long Lanky Larch Needles

[W3rk]

I have my first 2 Larch that I picked up late last winter. They've generally grown really well, though they've suffered some in the summer heat. These are supposed to be Larix kaempferi/Japanese Larch. The needles have always seemed very long.

I just recently took a trip up north to NH where I saw some native Larch - presumably Larix laricina. I noticed that the needles on these, even growing in shade, were significantly shorter/better looking. Easily half the length of those on my Larix k. - which I thought were supposed to have a shorter needle. Am I missing something?

Pictures for reference, my Larch:


And native North American Larch:

 

[WNC Bonsai]

I have a pdf articel by Vance Wood and he describes this kind of growth for a collected larch he had in Michigan. He repotted it in a mix and added 50% sharp fine sand and the next year it developed shorter needles. Here is a link to the article: http://mababonsai.org/eastern-larch.html

PS—If a white banner appears just tap the page a couple times to make it go away.

 

[W3rk]

I have a pdf articel by Vance Wood and he describes this kind of growth for a collected larch he had in Michigan. He repotted it in a mix and added 50% sharp fine sand and the next year it developed shorter needles. Here is a link to the article: http://mababonsai.org/eastern-larch.html

PS—If a white banner appears just tap the page a couple times to make it go away.

Thanks Cofga! That article is right on point for my issue. Looks like I'll need some sand/silica to try re-potting them next spring. I wonder how a heavy DE mix would work for this also?

 

[WNC Bonsai]

I’ll let you know in a couple years how this works. My usual bonsai mix is 4 parts pumice, 4 parts haydite, and 1 part tree bark. For my larch I mixed this bonsai mix with fine sand 1:1. The resulting mix drains like crazy but the fine sand seems to stay moist enough. The trees arrived in their little plug pots and were in a very organic peat mix. Their needles sound pretty much like what you describe for yours so I’m hoping this sandy mix will work.

 

[M. Frary]

I believe tamaracks have shorter needles to begin with.

 

[leatherback]

@Vance Wood , do you have a picture of the material you use in the Larch potting mix? I have a hard time visualizing what to look for. Any pictures of the effect would be great!

 

[WNC Bonsai]

Thanks Cofga! That article is right on point for my issue. Looks like I'll need some sand/silica to try re-potting them next spring. I wonder how a heavy DE mix would work for this also?

I think the magic addition was the very fine filter sand. Not sure whether that affects the root growth or whether because of its fineness it tends ot hold more water.

 

[M. Frary]

Tamaracks have naturally shorter needles than the others.
The soil has nothing to do with it.
Mine are D.E. and lava. They're just as short or shorter than the ones in the landscape.

 

[jeremy_norbury]

I think this is a normal difference between young growth and mature growth.

I have even bigger differences than this on the same tree. in training where I have left a sacrifice trunk to grow freely.

 

[WNC Bonsai]

Tamaracks have naturally shorter needles than the others.
The soil has nothing to do with it.
Mine are D.E. and lava. They're just as short or shorter than the ones in the landscape.

Well hopefull @Vance Wood will address this question at some point as he made quite an issue of it in his writeup on growing larch trees.

 

[W3rk]

Tamaracks have naturally shorter needles than the others.
The soil has nothing to do with it.
Mine are D.E. and lava. They're just as short or shorter than the ones in the landscape.

Thanks Mike, that's good to know. I'm really borderline for maintaining Larch in my zone. But if I think I can keep them going here I'll have to look into a couple of starter Tamarack/North American Larch.

 

[M. Frary]

Thanks Mike, that's good to know. I'm really borderline for maintaining Larch in my zone. But if I think I can keep them going here I'll have to look into a couple of starter Tamarack/North American Larch.

I'm not sure they like it that warm. It says you're in zone 7.

 

[crust]

My opinion: Jap larch has longer needles than American larch; anything that induces fast root growth(especially non-fine root growth) i.e. root disturbance, repotting; fertilizer makes for longer needles, endless rain can make for floppy needles; fine, divided, slow-growing roots make fine foliage--coarse, explosive, fast-growing roots make for coarse growth; root bound larches grow fine; larch in loose coarse uninhabited soil grow coarsely, Low down for me on finished larch is to keep the root balls tight and contained, the soils fine, repot sections or lightly rather than massive root disturbance, generally fertilize only late season and with restraint. To start with I'd say come spring repot you Jlarch and develop a finer root system and it will settle down.

 

[W3rk]

I'm not sure they like it that warm. It says you're in zone 7.

That's what I meant when I said I was borderline for this zone. There's a chance they won't survive here long term because of our summers.