Keyhole gardens: a drought-friendly twist on raised beds

Modern versions of keyhole gardens use patio-friendly shapes, such as this one from Vita Gardens. The technique uses an integrated composting system through which the garden is watered.

By DEAN FOSDICKAssociated Press

Americans whose gardens have been toasted by drought might consider a landscaping concept from Africa. It’s called keyhole gardening, and some believe it’s the ultimate in raised-bed design: a sustainable combination of composting and planting.

Keyhole gardens are small — typically no more than 3 feet high and 6 feet in diameter — and look like iconic keyhole shapes when viewed from above. From the side, they can resemble a tall earthen pie with a giant slice taken out.

They don’t need fertilizer, use 80 percent less water than the normal backyard patch, tolerate hot climates and are easier to tend because they’re at waist level.

Keyhole gardening was pioneered in Africa and became popular there again recently through initiatives by humanitarian aid groups.

A keyhole garden’s primary asset is drought tolerance, although it also works in temperate climates, said Eddie DeJong, co-founder of Vita Gardens in Sarnia, Ontario. The company makes keyhole garden kits.

The gardens get their nourishment from compost and water poured down an open-ended tube in the middle of the garden bed.

“After the garden has been established, it should be watered primarily through the compost basket and less and less around the bed itself,” DeJong said. “This trains the vegetables to grow deep roots down to where the moisture and the nutrients are.”

Structural components commonly include native and recycled materials such as straw bales or bricks.

Some commercial kits offer a more tailored look for use on patios and decks. DeJong said his company is working on lighter, more compact sizes for keyhole gardens, and aluminum and composites for a modern, urban look.

Keyhole gardens have proven to be more productive for nursery owner Rose Marie McGee than regular raised beds.

“Some of this is probably due to the hundreds of worms the keyhole garden promotes,” she said. “And an abundance of worm castings is one of the best fertilizers and soil conditioners.”

The Associated Press