“Garden Allies” began ten years ago as a forum to share stories about the art and science of conservation biological control; those beneficial insects that keep our gardens thriving, full of life, and beautiful. Before long we branched out to include pollinators, birds, soil organisms, and a myriad of sometimes unrecognized players in garden ecology. Revealing the occasionally mysterious roles of these garden denizens has been illuminating—not only for readers, but also for author, illustrator, and editors. We’ve had some fun along the way: fall issues covered “spooky” topics including spiders, bats, earthworms, and decomposers. How many readers noticed that for three years, springtime “bird” stories were followed by summertime “bee” topics?
The untold story that remains is our own.
Every animal on earth relies on plants for survival—sometimes directly (herbivores), sometimes indirectly (carnivores), and sometimes a bit of both (omnivores.) The first gardens were undoubtedly utilitarian—cultivated for food, medicine, fiber, and other human needs, but appreciation for gardens’ ornamental value was surely not far behind. Throughout much of garden history, pollination was taken for granted, but herbivorous insects and other animals have long been viewed as competitors. The first enclosed gardens were very likely designed to keep out large hungry herbivorous animals, and we found creative, sometimes highly toxic, ways to battle plant-eating insects. As our human population grows, and concerns about pollinators and environmental health mount, strictly ornamental gardens, kept insect-free with pesticides, are falling from favor.
Attention to pollinators has raised awareness of the interconnected nature of life in our gardens and the surrounding wild landscape. If we want butterflies, we must provide for caterpillars—most of which require regionally native plants, as do most herbivorous insects. If there are lady beetles, they must have sustenance—often in the form of aphids. Ninety-five percent of all terrestrial birds feed their babies insects, mostly caterpillars. If we like birds we must accept, and even welcome, a little imperfection in our gardens and explore the underlying ecological relationships.
In the end it is up to us, as garden allies, to commit to environmentally sound practices and to encourage others to adopt them. Nurture your soil, the foundation of any garden. Learn which plants and design principles will attract beneficial insects of all kinds.
Stop using pesticides.
Plant native milkweed for monarchs. Ask your local nurseries to stop selling invasive plants. Create wildlife corridors with habitat hedgerows and encourage your neighbors to do the same. Grow some of your own food, start a worm-composting bin, and learn about seed saving. Read Bringing Nature Home by Doug Tallamy. Join your local native plant society and botanic garden and make some new friends. Volunteer there, or at your local school garden—they teach the next generation—and they need your help!
Botanic gardens are playing an increasingly important role in plant conservation and modeling sustainable landscape practices. The American Public Gardens Association has committed to increasing sustainable practices at member gardens, and to teaching the public about climate change. Public gardens are organizing collaborative seed banking efforts, planting pollinator gardens, and conducting research. At the Santa Barbara Botanic Garden, an exclusively California native garden, we participate in the California Phenology Project, a citizen science initiative that tracks seasonal changes in plant life cycles. We conduct research on which California native plants are best at supporting pollinators and other beneficial insects and teach classes on conservation biological control.
As the Pacific Horticulture “Garden Allies” series draws to a close, the work continues. What’s next? We must all continue to share the best ways to create habitat and work to connect the urban heart of our cities to our wild landscapes. As for me, it’s time for a walk in the garden to see which allies are out and about today!
The author wishes to thank the many scientists and other experts who have contributed to a deeper understanding of conservation biological control, corrected innumerable errors, and shared their excitement about the natural world and gardens (the usual terms apply—remaining errors are the author’s.) Much gratitude is also due to my editors: Richard Turner, who first invited me to write “Garden Allies” and was an early champion of conservation biological control, and Lorene Edwards Forkner, who has shepherded the series to its conclusion. Thanks to Craig Latker, who produced dozens of beautiful drawings. Finally, thanks to you, the readers, who have made it such a pleasure to write for Pacific Horticulture.