Written by Katherine, Landscape Design Associate
Have you ever pollinated by hand? It’s a tedious task, best left to the experts: bees, moths, birds, bats, even the less favored wasps and flies. Butterflies are excellent garden pollinators, for their behavior is to dart quickly between flowers. They’ll uncurl their tongue-like proboscis and dip swiftly into the flower’s nectary. This is the flower organ containing a sweet mix of sugars and nitrogen-rich amino acids. As the butterfly dips from one nectary to the next, they’ll play a major role distributing pollen for a seedy future.
What kind of flowers and plants do butterflies prefer? And, how can we encourage them in our gardens? Chances are, your garden already includes some excellent butterfly habitat requirements.
Butterflies like some open areas to bask in the sun. Bare earth and large flat stones are where the butterflies like to take five.
Although they are some of the strongest fliers, butterflies enjoy some protection from the wind– it keeps bad hair days to a minimum. Larger plants, a fence or house can provide that coverage.
A moist patch of soil provides not only minerals, but enough liquid to quench the thirst of a kaleidoscope of butterflies (ie, many butterflies).
We know that butterflies love nectar, but let’s not stop there. Did you know they’ll also draw up sugary fuel from animal droppings, tree sap, and rotten fruit. Ok, that’s enough. When it comes to flowers, (more likely the focus of your garden), butterflies tend to frequent flowers with the following characteristics:
Bright colors. Reds, purples, oranges, and yellows.
Planted in clusters. A large patch of the same flower and color will attract pollinators better than a mix of several plants. The goal is to form a color block of at least 3 x 3 feet. Massing perennial plants or planting a shrub that will fill 25 square feet is an ideal way to attract butterflies and other pollinators. It also helps ensure flowers will receive pollen from their same species.
Nectar guides. This is an area on the center of the flower that reflects low ultraviolet light. We can’t see it without special camera filters. The colors and patterns attract and guide pollinators right to the nectar source.
Ample nectar supply. Not every flower contains nectar. In fact, orchids are known for their tricky ability to attract pollinators by their form and odor, without offering nectar in return. Fortunately, there are plenty of flowers offering butterflies a plentiful reward—Dianthus, Salvia, Pentas, Plumbago, and Yesterday Today and Tomorrow are perennial plants with a generous source of nectar. Bottlebrush (Callistemon sp.) and Dwarf Royal Poinciana (Caesalpinia pulcherrima var. flava) are two medium-size trees (10-15 ft) that attract monarchs and other butterflies. Annuals such as zinnias, sunflower, and cosmos are excellent nectar fodder. And culinary herbs, such as mint, sage, basil, rosemary, oregano, and chives, have lovely spikes of inflorescence. Three drought tolerant native plants that butterflies hang out with and look great in garden beds are Pohinahina (Vitex rotundifolia), Akia (Wikstroemia uva-ursi) and Koʻoloa ʻula (Abutilon menziesii). Ko’ola ‘ula is a Hawaiian endemic plant in the Malvaceae family and federally listed as an endangered species. Recently, this hibiscus relative has become commercially available as a cultivated plant.
Bloom time and species variety. In addition to clustering same-species plants or letting them grow into a larger area, choosing a variety of species will ensure a healthy nectar supply throughout the year. Pohinahina for example, blooms year-round, while Akia blooms mainly from Fall to Winter.
In addition to the flowers that produce nectar, certain plants provide the requisite stage for butterflies to play out their four-part life cycle. From eggs to pupae to chrysalis to adult winged insect, butterflies are the masters of metamorphosis. As butterflies go through these transformations, they seek out specific plants for egg-laying and to feed upon as caterpillars. In Hawaii, we have several plants important to the life cycle of our two native butterflies. The Koa butterfly (Udara blackburni) lays its eggs on the leaves of the Koa tree (Acacia koa).
The eggs develop into caterpillars who munch on the leaves of Koa, A’ali’i (Dodonea viscosea) and Mamaki (Pipturus albidus). Once the caterpillar has fattened up, it hangs upside down and molts. Its skin hardens into the chrysalis, a protective case. After emerging from the chrysalis as an adult, the butterflies feed on the flowers of Koa, A’ali’i as well as ‘Iliahi (Santalum ellipticum, or coastal sandalwood).
Mamaki (Pipturis albidus) is also the host plant for the Kamehameha butterfly (Vanessa tameamea). The Kamehameha butterfly is the state insect of Hawaii. As adults they can be spotted in the forest, feeding on the trunks of Koa, slurping on bubbles of sap. To illustrate their wide habitat range, they can also be found drawing nectar from the low-growing coastal shrub ‘Ilima (Sida fallax).
Other examples of host plant and butterfly couplings in Hawaii include:
Lilikoi (Passiflora sp.) and the Gulf Fritillary (Agrualis vanilla)
Citrus trees (orange, lemon, lime, grapefruit, and tangelo) and the Citrus Swallowtail Butterfly (Papilio xuthus)
Hibiscus and Bougainvillea and the Cloudless Sulphur butterfly (Phoebis sennae)
Crown flower or Puakalaunu (Calotropis gigantea) is a host plant for the Monarch butterfly. Belonging to the Milkweed family, Crown flower is sometimes called Giant Milkweed. Originally from India, Southern China, Malaysia and Indonesia, this tropical milkweed is now cultivated throughout the world. The plant thrives in full sun, will reach heights of 8-15 feet, and can handle moist to dry conditions. While a hatching of monarch caterpillars may quickly tear through the leaves on a healthy plant, its robust nature can stimulate a full recovery.
Attracting butterflies into your garden is one way to build connections between your space and the environment. Enhancing butterfly habitat in the garden can be a fun activity for any age and is bound to incur fascinating discoveries. Please share with us any interesting butterfly activity you have noticed in your area!
Here is a list of weblinks to further your engagement on this topic: