Cloud Pruning: A Japanese Art for Beautiful Gardens

Cloud pruning, or niwaki, is a distinctive Japanese method of shaping trees and shrubs into cloud-like forms. Known for its aesthetic appeal, this technique doesn’t just fit Japanese gardens but can complement many other garden styles. The term « niwaki » translates to « garden tree, » emphasizing the artistry and patience involved in crafting these living sculptures.

What Plants Work Best for Cloud Pruning?

Several types of plants are suitable for cloud pruning, especially those with interesting branch formations. The most common plants include:

Box (Buxus sempervirens)
Yew (Taxus baccata)
Pine (Pinus)
Japanese Privet (Ligustrum japonicum)

Other interesting options are Phillyrea latifolia, Luma apiculata, Japanese holly (Ilex crenata), Camellia japonica, and Osmanthus x burkwookii.

While deciduous plants, which shed leaves in winter, can be cloud pruned, evergreen species tend to offer more striking results, providing visual interest year-round. When choosing a plant, consider its natural branching structure, as this will form the foundation for your design.

When to Prune

Prune your cloud-pruned plants in early or late summer using secateurs or shears. Some fast-growing species may need trimming twice a year to maintain their shape. If you’re working with flowering shrubs, prune them after they’ve finished flowering to avoid removing their blooms.

Starting Your Own Niwaki

You can start cloud pruning with plants of any size. Smaller plants are generally more affordable and offer greater creative freedom, while larger plants save time but come at a higher cost. If you’re aiming for an established look quickly, consider buying a pre-trained specimen.

To shape your own cloud-pruned tree:

Choose the Right Plant: Look for one with interesting, uneven branching. Perfect symmetry isn’t necessary – some of the most captivating cloud shapes come from asymmetry.
Plan Your Design: Decide which branches to keep and how the final shape will appear. Remember, it may take a long time for removed branches to grow back.
Prune Carefully: Use pruning shears or a saw to remove unwanted twigs and branches from the center, leaving the main branches exposed. Focus on shaping the outer ends into cloud-like forms.
Encourage Growth: If you want the plant to grow taller, avoid pruning the growing tips. Once the desired height is reached, trim the tips to encourage branching and fullness.
Manipulate the Shape: Use stakes or weights to adjust the positioning of the branches as they grow, helping maintain the cloud shape.

Maintaining Cloud-Pruned Plants

Once shaped, cloud-pruned trees and shrubs need annual maintenance. Trim them in early or late summer to keep their shape intact. For plants with larger leaves, secateurs work better than shears to avoid rough cuts that are more noticeable on bigger foliage.

Some common choices for cloud pruning, like Japanese privet, grow quickly but require frequent trimming to maintain the desired appearance.

Problems and Considerations

Cloud pruning is generally trouble-free, but it does require patience and sharp tools. Unlike bonsai, which are grown in containers, niwaki trees are cultivated in the ground. The main distinction lies in their growth method, not their size. While both are revered art forms, niwaki trees grow to their full size in the garden, not a pot.