They're probably more accurately described as drift gardens, where free-spirited ornamental grasses are arranged with drifts of perennials and bulbs.
These gardens contain native prairie plants, as well as others matched to local conditions.
An established prairie garden usually requires little care - no fertilising, no weeding, no spraying and no watering - and it's ideal in locations where water conservation is a problem.
By now you'll be getting the drift of why I'm finding the concept so appealing.
The first step in making this style of garden is selecting and evaluating the site to see what kind of prairie would naturally grow there.
I'm in trouble already because the hot, humid Far North is not known for its prairies.
If you're in the central South Island, though, you're quids in, because prairie plants evolved in regions of temperature extremes, with scorching summers and frigid winters, and not much rain.
And whatever the other conditions, prairie plants need heaps of sun, so a location out in the open, away from trees, is good.
If you're talking real prairies then you're talking grassland, because as much as 80 per cent of a prairie's natural vegetation would be grasses.
That may prove a tad uninspiring in a domestic garden, so other plants need to be included, if for no other reason than because a residential prairie can't go on forever, and at some point has to be merged into whatever is happening nearby. A couple of hectares of tussock bordered by camellia hedge might look a bit uncomfortable.
Using rocks and old timber to define edges, and agricultural relics to provide visual relief within the planting can also ease transitions.
If you're looking for authenticity you'd best start trawling the junk shops for a set of bison horns.
Besides grasses, put together a list of flowering plants.
If you plan it well, your prairie garden should be in flower from spring till autumn as one flowering succeeds another.
If you can bear in mind bees and butterflies in your choices, you'll have another desirable element in the garden.
Most prairie plants are perennials and can be put in as transplants or seeds.
But if you're buying premixed seed packets be aware that you won't have much choice about colours and varieties and, heaven forbid, you may end up with lots of yellow.
PLAN BEFORE PLANTING
In any area of mass planting planning is the key to success. It's not a style that lends itself to random choices and it depends on self-discipline for success.
Grasses are ideal for this type of garden and in New Zealand we're spoiled for choice. They're not always easy to grow where it's hot and wet, but there are varieties that will manage if you care for them well.
If you have the right conditions, on the other hand, your plants should be carefree.
When you've planted enough of them they'll play nicely with a variety of other plants. The tussock and lupin landscapes of the Lindis Pass are a case in point. Choose three or four varieties and plant each in a curving swathe about 1m wide. This works really well on slopes and lends itself to a series of plants in similar colours, such as blue tussock, lavender and dietes.
Be disciplined - stick to your plan unless there's a very good reason to deviate. Needing a magnolia is not a reason. If you think you may succumb to the need to put one amid your tussock patch, the prairie style is not for you.
Sussex Prairie
Sussex Prairie Garden is a 2.4ha garden with naturalistic planting, created by Paul and Pauline McBride. It looks relatively mature despite being quite new - one of the great advantages of perennial planting. The garden is surrounded by mature oaks, with views of the Iron Age sites of Chanctonbury Ring and Devil's Dyke. As well as being of great interest to garden lovers, the farm also boasts rare-breed sheep and pigs living in the oak woods.
After 12 years working on a major garden design project in Luxembourg, during which Paul and Pauline were lucky enough to work with Piet Oudolf, the renowned Dutch garden designer, nurseryman and author, the Sussex Prairie Garden was conceived.
The garden features many unusual varieties of herbaceous perennials, veronicastrums, thalictrums, persicarias, sanguisorbas, kniphofias and hemerocallis. Huge drifts of ornamental grasses and asters extend the season of interest, and there are dozens of varieties of miscanthus, panicums, molinias, sporobolis and penisetum. Conveniently, there's a B&B at Sussex Prairie Garden.
