“Dart’s Gold” Ninebark offers a pop of chartreuse through the dappled sunlight. Submitted photo

St. Patrick’s Day is all about the “wearin’ of the green,” but did you ever consider the “growin’ of the green” in your landscape?

In high school biology, we learned that plants use the green pigment chlorophyll to photosynthesize, removing carbon dioxide from the atmosphere and releasing oxygen in the process.

Chlorophyll appears green because it absorbs blue and red light. What you may not realize is that chlorophyll is several pigments; the primary ones are chlorophyll a and chlorophyll b. Both absorb different wavelengths of blue and red light and appear in our plants as light and dark green, respectively.

Other pigments that affect vegetation color in addition to chlorophylls are: reds and blues (anthocyanins), yellows (flavonoids) and oranges (carotenoids). So how does this return us to St. Patrick’s Day and the “growing’ of the green?”

These pigments all combine in various plant species — cultivars and natives — to provide us with a myriad green shades for our gardens and landscapes. Research has shown that green, found in the middle of the color spectrum, is easy for humans to see and can be restful and calming to view.

Color is a hue, which is the true color produced by the plants’ chlorophyll pigments. Tint (lighter hue), shade (darker hue) and tone (less bright color) further enrich the depth of green in foliage.

When we look at the cultivated and natural landscape, it is generally dominated by green-colored foliage: trees, shrubs, perennials, annuals and turf. We can play upon tints, shades and tones of green foliage when we design gardens and landscapes.

Blooms, regardless of plant type, offer us a rainbow of colors to enjoy. However, the enjoyment is not long-lasting, as flowers wilt and fade in a short period of time; the green of foliage is with us for much longer. Showcasing green foliage with an array of leaf sizes and shapes, textures and variegation in combination with colorful blooming plants increases the richness of any garden or landscape. Here are a few plant ideas for incorporating tints, shades and tones of green in your gardening and landscaping plans.

The green hue in the “Flame Thrower” Redbud leaves contrast against the various green shade perennials. Submitted photo

Dark shades of green are found in conifers and evergreen shrubs, but even these offer a variety of shades for consideration. Classic English yews (Taxus baccata) are popular evergreen landscape plants found in many sizes and shapes, from tall columnar to low creeping varieties. There are also many shades of green available in cultivars such as “Repandens Aurea” (green with yellow to cream edges) and “Standshii,” with yellow to yellow-green undersides. American holly (Ilex opaca) boasts dark green spine-tipped leaves. Look for the cultivar “Greenleaf” for deep, dark green, dense foliage. In contrast, the hybrid blue holly (Ilex x meserveae) has foliage with a distinctive blue-green shade, especially cultivars like “Blue Princess” and “Blue Prince.”

Rhododendrons (Rhododendron spp.) are found with a variety of hues that change with the seasons. For example, Rhododendron “PJM Elite” is a cultivar whose green foliage turns into a purple-reddish hue in the fall and winter. Use these shrubs as focal points to complement your year-round foliage and blooming perennials.

Native trees and shrubs such as redbud (Cercis canadensis) and ninebark (Physocarpus opulifolius) have cultivars that offer varying hues of green. The new foliage of redbud “Vanilla Twist” has a lime green/chartreuse tint. Ninebark “Dart’s Gold” foliage, also chartreuse/lime green in color, changes to a golden hue in the fall. A hedge of ninebark shrubs with varying tints and shades makes a stunning year-round display, while providing food and shelter for birds and wildlife.

Among perennials, hostas (Hosta spp.) are a favorite ground cover that appear in many shades of green from bright yellow green to a green that is subtly blue-gray. Some hostas have wrinkled or toothed leaves to also add texture, and others may be striped in whites or other shades of green for a little additional color.

The cultivar “Guacamole” has glossy oval leaves with a chartreuse-tinted center; the flowers are aromatic. The native wild ginger (Asarum canadense) has beautiful, dark green, heart-shaped leaves that form a solid ground cover. Also consider ferns as a ground cover offering many shades, tints and tones of green and assorted textures. Ostrich fern (Matteuccia struthiopteris) is deer resistant and Japanese painted fern (Athyrium niponicum) provides frosty green, white and red color as a ground cover. All of these plants work very well in shady, damp areas.

Continue the “growin’ of the green” throughout the seasons for interest, diversity and beauty in your home landscape. To learn more about adding green to your gardens and landscapes, visit Penn State Extension at extension.psu.edu/choosing-shrubs-for-your-garden or extension.psu.edu/principles-of-garden-design.

If you have questions about native trees, shrubs and gardening, telephone the Penn State Extension Master Gardeners of Butler County at the Garden Hotline at 724-287-4761, Ext. 7, or email the Master Gardeners at butlermg@psu.edu.

Mary Alice Koeneke and Lisa Marie Bernardo are Penn State Extension Butler County Master Gardeners.

Complementary shades of green are found in the “Guacamole” hosta. Submitted photo