Can Japanese moss (sugigoke) grow in hot weather?

Japanese moss is not easy to grow, people say. But how difficult is it? Does it grow in hot weather? Here’s how Japanese moss is surviving in Southern Japan, pretty much on its own. During summer, the temperature almost constantly exceeds 30 °C (86 °F), and it’s pretty humid in the area. But even without regular watering nor weeding, it looks like the mosses are doing okay with minimum attention. I must admit though, that they aren’t their prettiest condition. I think it’s surviving because of the amount of rain.

Left: Partly shady area. Moss is keeping its nice green color and velvet texture.
Right: A stone under full son. Brown is taking over.

The garden has areas that are shady, part shade, and full sun. And it seems that the amount of sun is making a big difference. In more shady area, it’s maintaining its nice greenness even in the midst of summer. But under full sun, brown starts taking over. All in all, it did not look too bad for an area that wasn’t getting much attention. So I would say moss has some resilience in a humid climate.

Sugigoke is one of the most common Japanese moss. It seems to be resilient enough to survive on its own.

Haigoke was also everywhere, this one seems to be overgrown.

Sugigoke and haigoke are growing together.
Under full sun, haigoke quickly becomes brown.

As far as survivability, it seems that humidity plays more critical role than temperature. If you live in a area that rains enough, it will be worth trying to grow Japanese moss. The key is to find as much shady, dump areas as possible. Even a small object will be helpful for moss.

It will be a lot of work to make moss your groundcover, because you have to have soil condition, amount of sunlight, water etc. in perfect condition. It will make more sense to use moss as an accent in small patches. Maybe by the porch, by rocks, or by brick rails. Something that are a couple of inches tall can create some shades for moss at least for a couple of hours a day.