Beyond Natives

Eight exotics that belong in your garden

by

Anyone who knows me knows that I am particularly passionate about native plants—plants that have been in our area for millennia, co-evolving alongside our other species of life, creating sustainable symbiotic relationships that are crucial to our local ecosystems. Native plants have been altered very little by the hand of man; Native plants are going to support the most life, always. They are the greatest participants in our natural systems. 

That being said, I am no purist, and also adore, cultivate, and learn from many non-native species. In fact, one of the most exciting things about gardening in Louisiana is that we can grow such a variety of plants year-round. So many interesting tropicals from Central/South America and Asia thrive here and have helped shape the natural history and landscapes of southern Louisiana.

Recent years have brought several unprecedented weather extremes—from a polar vortex at the end of 2022, with temperatures staying below freezing for forty-eight hours straight; to a summer drought that killed enormous numbers of magnolias in the region; to the blizzard just a few weeks ago, which blanketed our landscapes with the most elegant pure white fathomable. I nerd out on times like these, as I observe my garden and how it responds to these phenomena. 

When such bizarre weather extremes hit us, I obsess over seeing who dies, who lives, and who flourishes. And these past few years, I have noted with interest the non-native species that have seemed untouched, trudging along happily alongside our native flora—all the while, not harming or reducing our native ecosystems. The list below comprises exotic plants that I believe have a place in our gardens. I have found each of them to be of great ease and utmost wonder.

Olive, Olea europaea: These trees are outstanding. They are lovely small evergreens native to the arid climates of the Mediterranean and Africa. This fact makes them outstanding in drought. Their petite stature and stout form make them a great tree to keep in a large terracotta pot, adding something special to any porch or courtyard. They also work well as an airy and textured privacy screen lining a fence. For such a drought tolerant plant, my olive is generally unphased by our great rainfall and flooding. Once established, it also does fine through our random hard freezes. My friends over at Suzanne Turner Associates harvest their fruit to cure and consume. Rumour has it that some universities out there are studying the tree for a potential olive oil crop in Louisiana. 

Mexican Salvia, Salvia leucantha: I plant and design with this perennial more than any other exotic plant. One of the prettiest and most robust salvias I have ever known, Mexican Salvia returns year after year with vigor and is an absolute hummingbird and bumblebee magnet. This plant thrives in drought and, like the olive, is unphased by our humid climate. Great en masse or standing alone, the plant’s gorgeous giant purple flower spikes bloom from spring to late fall. I cut it back at least once a summer to help it bloom even more. I plant these in gardens that get intense afternoon sun, are surrounded by excess hot cement, or for clients I know will not water well during the establishment phase. 

Chaste Tree, Vitex agnus-castus: Another Mediterranean native, drought-tolerant beauty is the vitex tree, with its prolific purple blooms that carry on for months and attract all sorts of pollinators. It’s a medium-size deciduous tree that grows incredibly fast and has an interesting form. Its growth is a bit rigid, with interestingly straight and architectural branching patterns. I have a lot of fun with my vitex trees, capitalizing on the bizarre branching angles and pruning them to almost look like large bonsai of sorts. They do well in a cottage garden, as well as alongside other more arid, drought-tolerant plants with similar muted colors, such as the aforementioned olive and salvia. The berries are edible and, when dried, resemble in look and taste, peppercorns.

Creeping Sedum: I inherited this lovely crawling succulent with the cottage I purchased three years ago. Ninety-five-year-old Ms. Peggy had it growing in all of the gardens she created over the past forty years. We changed the gardens completely, never trying to save any of this sedum—but it regrew everywhere. The plant is not invasive, but it seems to offer its services up in just all the right places, such as the edges of paths, and acting as a ground cover and weed suppressant in empty spots of the garden. It grows amongst my perennials in a fun and symbiotic way. I have transplanted it to dozens of clients' homes, and I grow it in my hanging baskets. The sedum handles filtered shade to full sun. It seemingly never has to be watered, yet is fine with however much rain it receives. No cold snap seems to affect it. 

Chocolate Plant, Pseuderanthemum alatum: This wild perennial native to Mexico and Central America has spotted brown, shiny leaves with deep purple blooms—a rare color combo assuredly. It can grow in almost full shade and reseeds beautifully, making almost a ground cover of sorts. It’s dainty, bizarre, and quite whimsical. My plant mentor, Lindsey, grows it in her shady back yard alongside other magical shade-loving perennials such as ajuga, jewels of opar, and varieties of begonia. She gave me a small bucketful a decade ago that I have spawned thousands from. It’s one of those weird plants I feel compelled to give away constantly and plant in every shady spot. 

Pineapple Guava, Acca sellowiana:  This is perhaps my favorite non-native fruit tree. A small and fast-growing evergreen with silvery foliage, its fruits make the perfect tiny tropical snack. Neither drought nor deluge seem to negatively affect the guava. She loves sun and, especially when pruned lovingly, grows into the most elegant branching form that makes her a focal point in the edible or permaculture garden. 

Night Blooming Cereus, Epiphyllum oxypetalum: The Queen of the Night! This sprawling cactus is just pure delight and magic and one of those plants that brings people together. If you are a gardener, you almost assuredly have given or received a broken off piece somewhere along the way. Just stick the cutting in some dirt or water, and it always roots. As the name implies, epic blooms open boldly as the sun sets, then fade away in the new morning. The blooms are somewhat rare, making it that much more special. Hawk moths drink from and pollinate these flowers, an epic sight to behold. Nightblooming cereus prefers a bit more shade but surprises me often in full sun. Protect them from freezing temps. I love to fill pots and hanging baskets on my porch with the cuttings I am gifted. They grow fast and are very drought-tolerant, making them a lovely choice for a container.

Angels Trumpet, Brugmansia sauveolens: I’ve saved the best for last—Angels Trumpet is technically a small tree, but depending on where you are in the state, the tale changes. You will find it in tree form in New Orleans and warm corners of Baton Rouge. In St. Francisville, it expresses a more perennial nature, returning from the earth each year. To me, this plant is of divine order; it is so very special to southern Louisiana and the old gardens we have cultivated here. You can often find one of these planted generations ago on old properties. Almost every Louisianan I know has a childhood memory made of banana plants and angel trumpet trees. They are another joy to bring you outside at night when their giant, sweet trumpet flowers burst open to entice large moths and bats to visit. The pollinator commotion surrounding the angel's trumpet is a show in and of itself.