Last week, I saw a couple of Ruby-throated Hummingbirds whizzing around the nursery and perching in nearby trees. I love spotting these tiny and shiny birds—the only hummingbird native to New England. Even though this is the only species we typically see on the East Coast, they really pull their weight as pollinators; many native flowers rely on these birds.
“Pollination syndrome” is a term used to describe how flowers have evolved to fit different niches. Flower shape, color, and scent vary from species to species in order to attract diverse sets of pollinators. The pollination syndrome for hummingbirds is also called ornithophily, literally meaning “bird love” or “bird affinity.” Ornithophily mostly includes tube-shaped, red and orange flowers. Bloom time is another factor in this pollination syndrome; a study published this May found that red and orange flowers* typically bloom later in the season, coinciding with hummingbird migration back north (McKenzie et al. 2025. Current Biology 35(9):2175-2182). Another study from this May explored the hummingbird preference for horizontally vs. vertically oriented flowers (Choi et al. 2025. Journal of Avian Biology 2025(3):e03449). Using Anna’s Hummingbird as a study species, they found a preference for horizontal flowers. The hummingbirds spent about 27% more time at these flowers, and they were able to extract more nectar.
Given this hummingbird pollination syndrome (horizontally-oriented, tube-shaped, red flowers that bloom later in the season) you might be thinking of the perfect New England hummingbird flower: Cardinal Flower! This beautiful wildflower is well-known to be a hummingbird magnet—it checks every ornithophily box! Because this flower is pollinated so well by hummingbirds, some researchers sought out to find if the range of Cardinal Flower aligns exactly with the abundance of Ruby-throated Hummingbirds (Coffey & Simons 2025. American Journal of Botany 112(5): e70034). The abundance of this flower was generally higher in the presence of hummingbirds, and bloom time tended to flower in accordance with hummingbird abundance. However, the ranges did not overlap perfectly. This likely means that although Ruby-throated Hummingbirds are a major pollinator of Cardinal Flower, they are not the only pollinators.
With many different flowers being pollinated by hummingbirds, how do flowers ensure that the right pollen gets to another flower of the same species? Another study published this May found that different flower species deposit pollen on different parts of the hummingbird’s body (Arteaga-Chávez et al. 2025. PLoS One 20(5): e0323577). This is an example of niche partitioning—a way for species that occupy the same habitat to reduce competition by using resources differently. In this case, the resource is the hummingbird! By depositing pollen on different parts of the hummingbird’s body, flowers reduce competition for real estate and prevent their own pollen from being displaced or buried. This allows multiple hummingbird-pollinated species to flower at the same time in the same area.
To support your local hummingbirds, check out our new Hummingbird Bundle!
–Jocelyn LaClair, Seasonal Horticulture & Sales Assistant
*Note: why hummingbird feeders are often red!
