@SLR2009, I don't have Yama Nishiki but have had a few Higasayama's that I struggle to keep alive. I've just lost my 4th one only yesterday. There comes a time when you have to say enough is enough. If you purchase one of the two, I would love to see a photo of it, perhaps on the 'cheering ourselves up thread'. They have such pretty leaves. Both are very similar IMO to answer your question.
@Acerholic I've purchased a Yama Nishiki recently. I wonder what you think that caused all four of yours to die.
Hi @acernoob and welcome to the maples forum. Sometimes you get a cultivar that just does not do well in a particular area. ( no rhyme or reason). Some are weak cultivars like Taylor and everyone has problems with, but as for Higasayama I've got one more that is doing OK, only time will tell.
@Acerholic sorry to here you lost a Higasa yama, Derek. My experience is they're not the strongest of maples, but not the weakest either. They do seem to throw a lot of dead wood. A caveat to the prevailing wisdom that Higasa yama doesn't revert. While this is usually true, sometimes older branches do completely revert and need to be cut out. So if a branch is plain green for several years, remove it; but don't remove new green growth, as it will almost always be the variegated type the following year. We have 2 fairly large ones of these in the garden. One started small, was browsed by a deer (who reduced all of our rose bushes to the ground at the same time) and started again. A couple of years later, it was stepped on by a deer (probably) and completely split almost at the graft. I duct-taped it together (was still too small to need a bolt) and away it went. This major damage is long healed and no longer visible. I have a picture I took of it with some other trees, attached. It's not very full, and I don't prune it at all except to remove dead wood. The other individual was purchased from Esveld as a larger tree, probably 2.5m. It's one of the few large JMs I've ever bought. Upon planting, it proceeded to die back on the main stem, almost to the ground. It grew back as a bush, and now looks OK generally. The variegation is more sharply defined on this second tree. On the first tree it is less typical in some parts of the tree, and the leaves don't come out quite as "hand-like". It may be that I need to get out the secateurs. My impression is the Higasa nishiki (which I don't have either) has a lot less pink in spring, and does not have the interesting "hand-like" leaf form at all. Some pictures of it seem to show a lot of green, when the entire plant is shown rather than a closeup of a leaf.
Out of curiosity, how did you lose four of them? Is it really that fragile? Was it bad soil, not enough/too much light, not enough/too much water, etc? It seems strange to be unable to keep one specific cultivar alive.
I really don't know tbh, I tried everything, different suppliers, change of positioning, increase in aeration in the soil mix. The only possibility is that they were all small. 1ltr pots. As Charlie @amazing maples said, " I don't buy small ones anymore, they just die". He has a point!!! Also E @emery said it is quite a weak cultivar. As a footnote, I'm trying one more, so much for my 3 strikes and out, Lol. I'll let everyone know how it goes.