Differences b/n San Jose and Prostrata Junipers? Please educate me.

[エドガー]

I’ve always wondered about the differences between these two (not much info on them on Google, aside from generic descriptions)… their natural growth habits and size (differences in heights and widths if left to grow out), foliage (same prickly juvenile and softer mature foliage?), trunk shapes contortions and bark, etc., etc.

I have 1 old, mature SJ, maybe +15yo (not too sure). I bought it as a big bonsai/niwaki in a 5-7gal container; but currently, I put it in the ground as a niwaki. It’s about 4.5’ wide and 2.5’ tall and trying to train it more upright.
Also have a bunch of cuttings/air-layers I took from it (some are now 1-2yo and some 3-4yo) and trying to grow them out and train them into informal upright, niwaki or big bonsai.

Ideally, I want them single trunk and informal upright, maybe 3-5’ tall. I believe their natural growth habit are lower and wider (prostrate) and short.
(not interested in Needle junipers nor Hollywood junipers… those grow too tall, big and/or too straight; and I’m also more just interested in what I already have, a bunch of San Jose)

Is it (easily) possible to grow and train SJ upright and into a tall niwaki or big bonsai? (instead of low and wide and short)
I’ve seen some really nice 3-4’ tall juniper niwaki at House of Bonsai in LA; but they are Prostrata and not San Joses. Are they that different?
What are the differences between Prostrata and San Jose?

Of course, House of Bonsai also has many big, tall Hollywood niwaki. But, those are much too big for my liking.

Would love to see pics of any tall, big, upright SJs if you have any. (as niwaki or big bonsai).

Pics attached are from House of Bonsai’s Prostrata niwakis (not their Hollywood). I really love that size, height and shape. Can a San Jose be the same and have that same potential (easily)?

 

[Shibui]

Prostrate varieties can be grown as upright trees provided they develop woody stems. We just need to stake or wire the trunks upright until the trunk hardens then it will stay in that shape.

A quick search shows that several different junipers are referred to as prostrata.

This bonsai site says the 2 are actually just different forms of J. chinensis - http://kuromatsubonsai.com/evergree...a-juniper-bonsai-and-san-jose-juniper-bonsai/ which would explain why you are having trouble working out the difference.

 

[エドガー]

Ah, that's what I figured - just gotta keep staking/wiring the leader upright.

Yeah... I've read that page/link and his website (and also his YT channel) several times in the past. Did he die? I noticed he hasn't updated his YT in several years. I really like his trees, style and teaching style.

It still doesn't state any particular, detailed, small differences bn Prostrata and San Jose though. I don't think anyone really knows, as I've never come across good info bn the two (natural growth habits like height and width if grown out, branch and trunk growth habits, juvenile and mature foliage, foliage and twig density or looseness, bark, rate and speed of growth, overall size differences, etc., etc.)