BENEATH THE CANOPY

Trees represent landscape royalty but you can create paradise below

Story and Photos by Norman Winter
@NormanWinterTheGardenGuy

Were the landscape a chessboard, then trees would surely represent the royalty – the king and queen to love and protect. Buying a home with native woodland or forest is like striking gold as so many of neighborhoods begin with the blade of a bulldozer.

Underneath the canopy of large trees, a tropical oasis can be developed. The monolithic leaves of this ‘Borneo Giant’ elephant ear provide the island magic along with coleus, begonias, impatiens, and even an Australian tree fern (Cyathea cooperi), whose fronds dangle from overhead.

Knowing that however can make developing the woodland garden a daunting task. Your garden under the trees however can be anything you want it to be; you are both the artist and conductor.

If you plan to garden on a heavily wooded site, first consider removing some of the underbrush and low hanging limbs. This author has begun his task on a woodland hill in west Georgia by waging war on an invasive Elaeagnus species that escaped years ago.

Trees are indeed the royals of the landscape. They should be cherished and treasured beyond all expectations.

Part of the project will be to remove small, weak trees that are too close together to develop or contribute to the overall effect. Gertrude Jekyll, famous writer and garden designer, advised tying a white ribbon around the trunks of the trees being considered for removal, then observed for several days from various angles before removing them. It is much easier to remove trees than to put them back!

Sometimes, limbing-up and thinning mature trees will not only provide more penetration of light but will also enhance the tree’s beauty by exposing its structure. Improving the soil in the woodland however presents challenges as the forest floor is obviously filled with roots.

LEFT: This Campfire coleus (Plectranthus scutellarioides ‘UF12221’), which developed a chartreuse margin, is the perfect partner for Carex ‘Everillo’. This fine textured grass-like plant yields terrific color in part-sun locations. MIDDLE: ‘Hartlage Wine’ sweetshrub has flowers as large as tennis balls. It is a remarkable understory small tree or large shrub with foliage that turns golden yellow in the fall. RIGHT: The forest floor can feel lush and alive with combinations of hostas and ferns.

Sticking in a shovel or trowel may quickly tell you the road that lies ahead and actually dictate some of your design. You may find tiny fibrous roots; these aren’t just any roots but small feeding roots. These normally will re-form quickly after planting small nursery stock. In most instances smaller is the safest bet.

You’ll also notice large anchor roots, some of these of which are as large as scaffold type branches. These roots are not to be cut, severed, or covered. Make it a goal not to cut anything larger than 1 inch in diameter.

Topsoil should not be brought in nor should there be attempts to change the grade. You may however bring in 4-6 inches of compost, rotted pine bark, peat moss, or similar material as needed for planting and light incorporation into planting area.

This comes with a strong word of added caution here as some trees resent soil work going on around their roots. Post oak (Quercus stellata) is a prime example. It is perhaps an exaggeration to suggest this tree may die by giving it a mean look. It is not a wild claim or stretch to say, though finicky about being disturbed, it is ever so rustic and picturesque in the landscape.

Most gardeners have never tried the ‘Black Flamingo’ flower (Chrysothemis pulchella ‘Black Flamingo’). The author grew these in both Columbus and Savannah in shady, under-canopy areas. The plants reach 12 inches tall, producing iridescent orange and yellow flowers and glossy foliage that is green on top and copper beneath. It’s not cold hardy, but it’s very easy to dig the tubers up for the winter.

There is much to rave about in developing a native habitat under your trees. Georgia is home to some of the most exotic looking native plants that can cycle in bloom throughout the long growing season.

Consider the wonderfully fragrant blooms of large shrubs like the native azaleas, the flaming orange (Rhododendron austrinum) and the pink and white R. canescens. You’ll be amazed at their ability to bring in butterflies and hummingbirds.

While those are obvious first choices the question would be have you paid attention to the two-winged silverbell (Halesia diptera), also called American snowdrop tree. This small rounded tree can reach 20-30 feet in height and width, but we normally see them multi-trunked and in the 8-12-foot range.

This native is cold hardy throughout the state, blooming in April and May. To see one in full bloom with the dangling, shimmering white blossoms is to fall madly in love with it, promising to search to the ends of the earth if necessary to obtain yours.

LEFT: There are many cold-hardy bananas that can be grown in Georgia. This ‘Black Thai’ in the foreground and flowering banana in the background sets the moods for this version of a Caribbean cottage like one might see on the island of Saba. MIDDLE: The jewel of Burma (Cucurma roscoeana) excels as an understory planting giving a most exotic appeal. Cucurma gingers, which for the most part go through winter dormancy, offer some of our best cold-hardy choices. RIGHT: The shampoo ginger (Zingiber zerumbet) is among the most unique for the tropical garden. The blooming talk arises separately from the foliage. The cone is actually a cluster of bracts with small yellow flowers. The cone matures from green to red as summer comes to a close.

Then there is fetterbush (Lyonia lucida). Desperately needing a marketing firm, this azalea relative is evergreen and reaches 3-5 feet in height. It is cold hardy from Zones 7 and warmer. It has open arching stems with dangling pink blooms treasured by bees. Blooming season runs March through May.

The list of must have native plants for understory plantings should include oakleaf hydrangea (H. quercifolia) and its superior selections such as ‘Snowflake’, as well as sweetshrub (Calycanthus floridus) and its hybrids, such as ‘Hartlage Wine’, ‘Aphrodite’, and ‘Venus’.

Remember, I said you are the artist and conductor and if you want steel drums and tropical magic then there is no better place than in the shifting light under large trees.

Gingers are a great place to start and Hedychium species and cultivars are some of our best – cold-hardy, fragrant, and loved by hummingbirds. The white butterfly ginger (H. coronarium), yellow apricot ‘Ann Bishop’, and the yellow gold ‘Kahili Ginger’ are just a tiny sampling of those cold-hardy in Zones 7b-10

Curcuma gingers are also terrific choices. While there are some certainly more tropical when it comes to temperature, you’ll find a more than enough cold hardy in Zones 7b-10.

‘Emperor’ variegated hidden ginger (Curcuma petiolata ‘Emperor’) is a relatively new hybrid. Many references suggest only warmer zones and full sun. Those of us that have been growing them for years know the lushest look comes with afternoon shade and yes, they will die back but return. The key to that is good winter drainage.

LEFT: Variegated shell ginger (Alpinia zerumbet ‘Variegata’) will probably never bloom at your house, but the foliage is so luxurious and exotic in the filtered light garden, it is a must-have plant. MIDDLE: Hedychium gingers in bloom, such as this ‘Ann Bishop’, are favorite feeding locations of ruby-throated hummingbirds. RIGHT: Fetterbush is native to southern Georgia and is cold hardy from Zones 7 and warmer. It forms a picturesque arching shrub beneath the canopy of tall trees.

Your tropical oasis would not be complete without bananas and elephant ears – the foliage drama queens of the landscape. Cold-hardy bananas, such as the Japanese fiber (Musa basjoo, Zones 5-10) will survive throughout the entire state, dying back to the ground but returning in the spring. The flowering banana (M. ornata) and ‘Black Thai’ (M. bulbisiana ‘Black Thai’) will return in Zones 7-10.

When it comes to elephant ears (Alocasia) remember names like ‘Regal Shields’, ‘Portora’, and ‘Borneo Giant’. All of these defy logic with the size of their leaves and promise a spring return in Zones 7b and warmer with good winter drainage. They are also easy to dig for winter storage in colder areas.

Ferns, native and imported, are naturals for the forest floor. Hosta excel in all but the extreme South and though not tropical, they have to be among the most welcome plants in the woodland garden. They will fit any style – tropical or otherwise.

Trees are indeed the royals of the landscape. They should be cherished and treasured beyond all expectations. Most of them will allow you enhance their beauty by creating and understory paradise of your choosing.