Keyhole Gardens Designed for Texas’ Extremes

With their small size, flexibility and durability, keyhole gardens have taken Texas by storm, offering people a chance to create a thriving garden in a small amount of space and also using a minimum amount of water.

Keyhole gardens, which are usually about 6 feet in diameter and up to 3 feet high, first became popular in Africa, and have become common throughout Texas because of a design that allows them to thrive in hot and dry conditions which are common in our state.

“If you are interested in a garden that uses recycled materials, uses much less water and recycles your kitchen waste, a keyhole garden may be for you,” McLennan County Master Gardener Melody Fitzgerald told Waco Today magazine. “One of the best features of this method is that you can stand up while gardening. There is no bending over to care for your plants or to harvest your vegetables because the bed is at least 3 feet off the ground.”

A notch in the keyhole garden resembles a pie slice, and a hole in the center of the garden contains a composting basket that moistens and nourishes the soil. Materials such as fall leaves or spring and summer grass clippings can be placed in the compost basket.

The gardens don’t require in-ground digging and are easy to maintain. There are multiple ways to set them up, from simple rock or wooden enclosures, and the design can either be simple or intricate.

The idea for the gardens was inspired by attempts to grow thriving gardens in hot and drought-stricken areas in Africa, so with that in mind, the gardens should also be able to withstand the withering Texas heat.

“It’s nothing short of amazing that the community of Clifton in Bosque County has been transformed into an oasis in this gardening desert with help from creative landscape architect Deb Tolman,” wrote Elain Acker in an article for Texas Co-op Power. “Leaning on her 30 years of experience in landscape design, doctoral studies in environmental science and research on African survival strategies, Tolman has (worked with numerous people) to unlock the secrets of sustainable gardening.

“A keyhole garden is the ultimate raised-bed planter. It is often built in the shape of a circle measuring about 6 feet in diameter that stands waist-high and is notched like a pie with a slice cut away. A hole in the center holds a composting basket that moistens and nourishes the soil. The garden, which from above looks like a keyhole, can be built with recycled materials and requires less water than a conventional garden.”

In addition to being able to take the heat, the gardens also offer an opportunity for people to save some money on grocery bills.

“You don’t have to spend $400 a month on groceries when you can grow healthy produce at home,” Tolman said. “In the summertime, I grow Malabar spinach, which loves the heat. The chard’s been going all year. I can eat a power snack of French green beans right off the vine.” Her harvest also includes carrots, kale, tomatoes, berries and more, rivaling Texas farmers markets. “I eat year-round from these gardens.”

Tolman provides lectures and workshops on keyhole gardening in locations throughout Texas and beyond and does so with the enthusiasm of an evangelist.

And why not? Keyhole gardens not only offer cost-savings opportunities, they also allow people to use significantly less water.

Keyhole gardening, combined with rainwater harvesting, offers a chance for significant financial savings and a way to conserve water at the same time.

If you need evidence of just how durable keyhole gardens can be, Tolman says look no farther than the scorching summer of 2011 for the best example. The gardens survived the drought and the intense heat. During that year, however, extra water was needed to keep her keyhole gardens from drying up.

An interesting feature of the gardens is that most of the soil Tolman uses consists of recycled cardboard, although manure is also used as a fertilizer.

When it comes to composting materials, old telephone books, cardboard and junk mail can be used to provide a rich source of carbon.

“You want it thick on the bottom to smooth out weeds,” Fitzgerald said. “Wet it down well. You can add vegetable waste if you have it.”

Adding layers of material will result in a compost pile for your garden. This compost not only provides essential nutrients for your garden, it also provides a heat source to help sustain the garden through the cold winter months.

A variety of different materials can be used to create the wall of the keyhole bed, and one that is often recommended is cinder block. Many people also use metal sheeting in creating the wall, as well, and chicken wire or mesh.

Tolman recommends planting the gardens very thick with seeds, and Fitzgerald noted that this provides a cover for the soil that helps keep the garden cooler and moister in the summer.

Recycling is a key component of successful keyhole gardens.

“You can put any kitchen waste you have into the bed, but stay away from meat as it can harbor bacteria and attract pests,” Fitzgerald said. “This garden method would be great for organizations that have acceptable waste to be composted, or for community gardening efforts.”

If you are interested in creating your own keyhole garden, Tolman offers a field guide for getting started here. Although many specifics are provided, she also encourages people to get creative and have fun in making their own designs.

With good planning and consistent care, keyhole gardens give you a chance to grow fruits and vegetables in a compact space that can deliver big results for your table or flowers to beautify your yard, and in a way that adapts to Texas’ sometimes harsh weather extremes.

The Brazos River Authority would like to thank the folks at sendacow.org and the gourmetgardening.co.uk for the kind use of their keyhole garden photos.