A Look at Leaves

Most gardeners, whether they realize it or not, are first drawn to a particular plant by the characteristics of its leaves, says master gardener Paul James. Much of the appeal of Japanese maples, for example, stems from their palmate leaves, which resemble fingers arising from the palm of the hand.

There is an enormous diversity of plant leaves, from those of the simplest blade of turfgrass to those of the colorful kale. The shape and arrangement of plant leaves are defined using elaborate terminology, with terms such as pinnate, peltate, palmate, lanceolate and hastate.

Leaf margins are one characteristic that can capture a gardener's attention. They range from smooth to saw-toothed. They may have deep cuts or more rounded lobes. Venation, or the pattern of veins on a leaf that make up a plant's vascular system, can be extremely captivating as well. This holds true whether the venation pattern is somewhat symmetrical or seemingly more subject to chance.

Leaf texture is varied from smooth to coarse and anything in between. Even the undersides of leaves can be interesting, as in the case of the Buddha's belly (Jatropha podagrica). Its topside is green, but underneath it's nearly white.

Take pines, for example. For centuries we've been drawn to their simple leaves, or needles. We even enjoy them off the tree, as evidenced by pine mulch which is popular throughout the country. The needled leaves of other evergreens, such as spruce, are equally attractive.

"The sword-like leaves of ornamental grasses clearly pique our interest, for these are among the most popular landscape plants around," says James, adding, "The same is true of daylily leaves."

The large leaves of the plumeria definitely make a statement, as do the fan-shaped leaves of the lady palm. In contrast, the delicate leaves of parsley are every bit as intriguing. And there's something to be said for the softer, more delicate leaves of plants like ferns.

"The boldest — and to me, the coolest — leaves of all can be found among the succulents. They have adapted their leaf structure so that they can store large amounts of water. This helps them survive in arid climates," says James.

Having a landscape full of foliage doesn't mean it has to be devoid of color. In fact many plants offer leaf variegation and colors in varying hues of green, yellow, orange, red and more. "Variegation is another eye-catching characteristic, which is why plant collectors and hybridizers are always on the lookout for new variegated plants," says James.

All this adds up to leaf appeal. Even popular flowering plants, when not in bloom, must have some foliage appeal or else we probably wouldn't grow them. "I prefer foliage to flowers because leaves provide interest in the form of textures and colors in a softer, more subtle way, whereas flowers tend to shout," says James.