Your question - I think it's a question - is a little vague :-) What exactly do you want to know? Where to grow them?.... how to grow them?......winter protection?.....in ground or in containers? And we need to know where you are located, as that can make a big difference in their requirements.

You may also want to peruse previous threads on this forum as there are lots that address most of these issues.

Moist, non-alkaline soil that drains well is important. Also if the climate is marginal a sheltered position may be needed. Specimens in pots or tubs may need protection if frigid winters are expected, as the roots of these plants can be comparatively prone to cold when not in the ground.

Oh sorry. I have planted a Japanese Emperor tree on a slope hill on north side of my garden in southern Ca area. It gets some direct & filtered sun. few months ago each leaf was half dry and couldn't fix it and it doesn't have any leaves and branches are drying out from the tip :( What is the problem and should I move it to a flat area?

"few months ago each leaf was half dry and couldn't fix it"

Once the leaves start to die there would be no way to change the damage you saw. Is the leaf loss now because its fall? Since they were planted on a slope did you check to make sure the roots were well watered?

tj

Dry leaves early in the season (well before fall) is typically an indication of insufficient water. And in SoCal in another serious drought year, that might be somewhat expected, especially if on a slope, which often offer fast/accelerated drainage. The soil for these trees needs to remain consistently moist - not too wet and never completely dry. And I wouldn't recommend irrigating these trees with a normal SoCal automated sprinkler system - a few minutes of water daily is hardly better than no water at all. JM's need a periodic deep and slow soaking at the root zone in times of drought, like once every 7-10 days at 30-45 minutes on a slow trickle.