GARDENING : Elegant Knot Motifs Are Long on History, Short on Upkeep

If you want to bring a little Elizabethan culture to your garden, plant a knot garden, which separates carpets of flora designs by using manicured hedges.

Traditional knot gardens, which are becoming quite popular in the Southland, comprise low, level beds of plants, ornamented with a pattern of intertwining lines made of dwarf hedges or clipped herbs. These “knots” partition the area into various sections holding different plant types and color schemes.

“Knot gardens seem like a lot of work to make and maintain,” says Kevin Campbell of Roger’s Gardens in Corona del Mar. “But they really are quite low-maintenance, requiring just watering and annual or biannual trimming.”

Carpet bedding is perfectly suited to today’s smaller gardens in intimate-size yards, courtyards or enclosed entryways. A simple design makes the best use of a small space.

Knot gardens had their origins in medieval kitchen gardens where medicinal and cooking herbs were divided into separate beds to prevent confusion. In Elizabethan times, knot motifs became popular not only for plants and gardens, but also for woodcarving, plasterwork and stained glass.

In these early gardens, inner beds for herbs, vegetables or flowers created the patterns. Later on, when gardens became more purely ornamental, the hedges themselves became the design focus and the spaces between them were filled

with earth, sand, brick or coal dust to enhance the pattern.

(Hedges surrounded by gravel are the easiest kind of knot gardens to maintain and look attractive all year.)

Parterres became part of knot gardens about the 17th Century. The designs, which are still popular today, used boxwood, flowers, grass and stone to create open scrolls, fluid arabesques and fleur-de-lis patterns.

There are three main types of parterres: parterres de broderie (boxwood edgings and colored earth imitating embroidery); parterres a l’anglaise (turf cut into patterns and edged in clipped boxwood); and parterres of cutwork (boxwood outlines filled with flowering plant).

To create a knot garden, select a sunny location (unless you are using shade-tolerant annuals such as coleus). Insufficient sun for most plants will result in sparse and leggy outgrowths, spoiling the pattern.

The early Tudor knot gardens were a cozy 10-to-12-square feet, which is a useful size in many contemporary situations.

Consider the elements you’ll use to make the knots: Annual or perennial flowers, boxwood, herbs, vegetables, grass, and gravel or crushed stone.

Boxwood is still the most popular knot garden plant, unsurpassed for clipping into velvety edgings and knot designs. It offers a bright green color, different from any other evergreen.

A garden made solely of boxwood and grass or gravel is a restful study in shades of green. But there are variegated types of edging box that add a touch of yellow and white to the picture.

Although grown mostly in the Middle Atlantic states and southern New England, boxwood will grow in Southern California. If you don’t do well with it because of the heat, a good substitute is the dwarf yaupon, a drought-tolerant holly that resembles boxwood.

Heller’s Japanese holly is another excellent substitute for boxwood, especially in cities where it thrives despite soot and air pollution. It will tolerate some shade and will grow 1 to 2 feet high.

Today, many dwarf evergreen shrubs are available that were unknown to the general Elizabethan gardener. You can plant these in lieu of--or in combination with--herbs and boxwood for a colorful year-round display.

Candytuft is easily maintained as low edging. In the springtime, it’s covered with white flowers. If sheared back after flowering, the plants will keep a neat dark green appearance.

Crimson pygmy Japanese barberry is always clothed in small red leaves that bring a sharp contrast to any knot design. Barberry is good for low designs, since it can be kept as short as 6 inches.

Any small-leaved variety of winter creeper can be used in a knot or parterre, although if you use it for ribbons, rather than for filling in, it will need frequent trimming. Many varieties have gold-and-green or white-and-green foliage.

Herbs add contrasting tones and textures to knot gardens. To maintain a trimmed appearance, lightly shear them every two weeks from the end of May to the end of July.

Thyme is available in a huge assortment of gold, silver and lemon-scented varieties. Select an upright plant rather than a spreading one to include in your pattern.

Santolina--also called lavender cotton--is an aromatic herb with gray foliage used for adding distinctive smoky lines or filling in beds.

Lavender is well-loved, both for its aromatic foliage and its spikes of flowers used for perfumes and potpourri. Munstead Dwarf is a smaller, more compact lavender that can add color if the common blue-flowering plant is combined with other varieties such as white Jean Davis and deep purple Munstead or Hidcote.

Hyssop is frequently recommended by Elizabethan garden authors. Unlike most herbs, it will grow in partial shade. In addition to its usual purple flowers and narrow, dark green foliage, hyssop can display white and pink blooms.

Rosemary responds well to clipping, forming a dense, low hedge of dark green needlelike leaves. When harvested, sprigs can be used in potpourri and are invaluable in cooking lamb.

Some other ideas for herb knots include wormwood, dwarf sage, rue, germander and thrift.

Flowers add brilliant color to permanent knots and parterres, and can be used alone to create Victorian carpet bedding schemes. You may want to try using annuals in your first attempt at knots since they are inexpensive and add instant style. Once the patterns are set, experiment with the more expensive perennial flowers and herbs.

Select compact, low-growing, free-flowering flowers.

Sweet alyssum, marigolds, ageratum, red salvia, geraniums and lobelia were 19th-Century favorites, and are good choices for sunny locations. In shadier spots, try impatiens and vinca. Coleus comes in a rainbow of colors that brighten dark, shady spots. Blood-leaf, Joseph’s Coat and other succulents come in many shades.

After selecting the flora, decide on a pattern. Many fancy-looking knot patterns are actually made of simple squares, circles and semicircles. They are easily laid out in the garden by marking out the four corners and center with string and stakes and taking measurements from these points. Less geometric designs are drawn out first on graph paper.

Divide the ground into equal number of squares with string and stakes, so each element can be enlarged proportionately. Once the guidelines have been marked out, the design is traced in the garden with ground limestone or white sand.

The final step is planting your knot garden. Regardless of the pattern or size of your design, you will need a lot of plants because each line is, in effect, a miniature hedge.

Plant in a single row along the strings, limestone or sand guidelines. Space the plants closer together than is generally recommended for the particular type of plant to help your design fill in rapidly.

Decide which lines act as continuous rows and then plant the remaining lines, leaving a space at the “intersection” where the lines cross.

Whether you use herbs, dwarf shrubs, annual bedding plants or vegetables, they should be trimmed back to encourage compact growth. This will give your knots a firm, tight line.

Once the row is filled in, trim the lines, either flat-topped and straight-sided, or rounded. For more contrast, you can use both silhouettes within the design.