The Ha-Ha: An 18th-Century Garden Secret for Modern Landscapes

Having trouble with animals wandering into your garden? Eighteenth-century English gentry had the perfect solution for protecting manicured lawns from marauding sheep and cattle—the sunken ditch, or ha-ha. Named for the surprise of suddenly encountering it, the ha-ha features one sloping side and a stone- or brick-faced wall; in simpler versions, a fence conceals at the bottom of a deep trench.

One of the ha-ha's greatest benefits is allowing an uninterrupted view from the garden while maintaining security—something many of us desire, even without grazing livestock. Modern garden designers now offer other permeable barrier solutions with similar benefits.

Here we see perhaps the closest contemporary equivalent to the traditional ha-ha. The wall neatly divides formal garden sections while allowing views into wilder, picturesque surrounds.

This example may be more retaining wall than true ha-ha, but it illustrates the principle: from the lower side, the wall creates a secure barrier unseen from the open garden above.

Installing such features is labor-intensive and costly, yet they last indefinitely with proper maintenance and can dramatically transform a landscape.

The ha-ha needn't be purely utilitarian. This beautiful stone wall would make a superb ha-ha: practical in construction, fitting into the landscape, and a striking feature in its own right.

Early 18th-century English ha-has lacked walls, consisting merely of a deep ditch with a concealed fence—simple yet remarkably effective.

In modern gardens, stone and brick aren't always the most suitable materials. Here, Cor-Ten steel forms a cost-effective barrier.

Perhaps the most realistic modern descendant of the true ha-ha is the infinity-edge pool: a swimming or reflecting pool that appears to extend to the horizon without an interrupting barrier. The ideal site is on a hillside where land falls away.

This sundeck with no edge is a close relation of the infinity-edge pool. As most of us live within barriers—walls of homes and workplaces—creating outdoor spaces without visual barriers can be important to our well-being.

We take this from three centuries ago, when English estate owners wanted to be part of their landscape. Landscape gardeners like Capability Brown introduced the idea of the landscape sweeping right up to the house, and the ha-ha made it possible.

Barriers, especially internal ones, in contemporary garden design don't have to be impermeable. We often want to delineate areas without blocking views through to the rest of the garden.

Grasses with tall flowering spikes create this type of soft barrier beautifully.

The rustic palisade fencing in this minimalist courtyard safely separates upper and lower garden areas while allowing views through and serving as an interesting feature itself.

This serpentine Cor-Ten steel fence undoubtedly has ha-ha ancestry. Gaps between uprights allow views through while creating a secure barrier. The serpentine shape offers different viewpoints as one moves through the garden.

The same idea employs semitransparent material to increase visibility without sacrificing security.

Though we've come far from sinking a fence in a ditch for an invisible barrier, contemporary designers still use the same principle—transparency with security—to create the perfect garden barrier.

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