You can easily design small Japanese garden. For me, this is a great question. And one, I wish to explore much more. I intend building a Japanese garden in the south of France when I retire.
The physical elements of a Japanese garden include at least some of the following: raked gravel, sand (usually one of the other), carefully selected and placed rocks, walls often with traditional tiles on the top, small trees (pruned) and bushes (pine and Azealia being very common), a pond or lake, often with carp within. There may be bamboo trees behind the garden. The balance of space to rocks/moss is essential, as in the famous stone garden of Ryoanji in Kyoto.
What Else Do You Need Other Than Physical Elements?
More than the physical elements is the philosophy/attitude derived from Zen Buddhism and also the abstract representation of the physical world. At Ryoanji, some say that the rock groupings amid lots of racked gravel (space) are a representation of mountain tops peeking through the cloud. Others see a tiger and her cubs crossing a river.
At any rate, zen gardens are designed to invoke calm and mediation. Therefore, a knowledge of the fundamental concepts of Zen would help understand the underpinnings of what makes a successful Japanese garden.
More On Japanese Gardens
Several books list the essential elements for creating a Japanese garden.
There are several types of Japanese gardens, including ‘strolling,’ Tea, and Zen. The strolling garden is as the name suggests a garden (usually a park) that you stroll around a see a changing landscape where hidden areas are revealed or viewed from a particular standpoint. The Tea garden made for tea ceremonies is more like a secret woodland ‘man cave’ where you relax and contemplate. The Zen garden, with its sunken natural stones set in raked gravel, is for meditation.
They all share the use of natural materials, wood, stone, water, etc. All include building an enclosure apart from the hustle-and-bustle of the outer world. A sort of natural diorama is there just out of your window.
There are several hospices in the UK that have Japanese gardens in them as they are considered to be therapeutic. The divisions of the JGS control most.
How Do Americans Design Small Japanese Garden?
Most American’s approach to gardening is to buy something you like and plant it somewhere. This also holds for Americans wanting Japanese style gardens. Often a gardener will add a tiny pond with a couple of small koi or goldfish and dah dah! Instant Japanese garden! Sometimes they’ll add some decoration that looks vaguely Asian, but for the most part, that’s it. Sadly, even high-end landscape designers in America are guilty of this. I looked over the credentials of one design firm and was optimistic until I viewed their portfolio of reference gardens. It consisted of about eight tiny gardens with tiny ponds and lanterns or Buddha statues. Other than that, the pictures looked like ads for Home Depot. Mind you, these people get paid a lot of money to design gardens and have made some impressive ones — just not Japanese ones. I still haven’t found a designer within a few hundred miles that can do a realistic-looking Japanese garden.