Spring has sprung, and here come the birds . . . but what about the bees?
Pollinators such as bees and monarch butterflies are on the decline, causing alarm among gardeners and biologists alike.
Two years ago, a species of bumblebee made the US endangered list for the first time. According to a study by the Xerces Society, the monarch butterfly population has decreased about 80 percent in the East since the 1990s.
In response, Lori Wolfe and Jean Shildneck, organizers of the seventh annual Gardening Green Expo held recently, decided to open a public dialogue about these creatures at Kennedy Country Gardens in Scituate.
Speakers discussed the theme of how people could “Plant for Pollinators.” Here’s what they had to say in interviews with the Globe.
Kenneth Pearl, a member of the Plymouth County Beekeepers Association, said we’d lose 75 percent of our food if pollinators go extinct. He said there are even some variations of food that can only be pollinated by bees, such as almonds and cranberries.
“Without pollinators, we don’t eat. If everyone wants to give up eating, then we don’t need pollinators,” Pearl said. “A wise man said, ‘If we lose honeybees we lose mankind.’ ”
Katie Banks Hone, known around Ipswich as the “Monarch Gardner,” said the destruction of pollinator habitat causes an overall decline in population, as shown with the monarch butterfly over the years.
The way to save monarchs is to foster biodiversity. Hone said people should plant native plants in their yards, such as milkweed, the only plant on which monarch butterflies lay eggs.
“Create habitat, create habitat,” Hone said. “[Pollinators] have so many issues with climate change and the habitat is the buffer that keeps them afloat. No milkweed, no monarchs.”
Hone acknowledged that although Monarch Watch’s data showed an uptick in this year’s population because of beneficial weather, she emphasized that relying on seasonal temperatures isn’t a sustainable solution for pollinators.
“Three years ago, the population went down 25 percent because there was a freak winter in Mexico that killed off millions,” Hone said.
Instead, people should cultivate gardens that support pollinators; this means planting native plants and curbing the use of pesticides that can destroy and disrupt other organisms in the environment.
“We need to have a habitat to act as a buffer when we have those bad years,” Hone said.
Barbara Passero and Jean Devine, the leaders of Meadowscaping for Biodiversityin Waltham, also stress the significance of native plants. They are better at resisting harsh environments, benefit animals and plants that interact with them, and use less water.
Wolfe also acknowledged that planting native plants for pollinators simultaneously encourages water-conservation gardening.
“We try to think of a new theme each year that ties in with water-smart gardening. Pollinators rely on native plants that are also drought-resistant,” Wolfe said.
According to Mass Audubon, five native plants to consider are butterfly weed, joe-pye weed, foam flower, columbine, and maidenhair fern.
However, it’s difficult to motivate people to choose native plants. “That’s the problem, really,” Passero said. “Even with gardeners.”
Pollinators also are suffering because of pesticides that kill them and their surrounding environment.
“A lot of nurseries have fertilizers that have chemicals,” Passero said. “Pesticides kill the bees.”
Still, all the speakers have hope.
“Everyone can do their part to contribute to biodiversity and mitigate climate change,” Devine said. “Plant native plants in your backyard.”
Here are some tips for your own garden.
■ Attract the bees: Pearl has found that his home-grown pumpkins, winter squash, strawberries, and raspberries greatly benefit from bee pollination. Dandelions are a native flower that’s easy to grow.
■ For monarchs, get milkweed: Hone said two species grow natively in New England: swamp milkweed and butterfly milkweed. Local nurseries sell them in June and each plant requires a square foot of space to grow.
■ Swap out your pesticides: Pearl shared his recipe for homemade pollinator-safe weed killer: Mix together one-third cup of blue Dawn dish soap, a gallon of white vinegar, and two cups of Epsom salt. Spray once on a weed after the morning dew has dried; “It should be gone that evening,” he said.
■ Exercise the power of supply and demand: Hone, Devine, and Passero recommend boycotting plants and fertilizers that have pesticides, especially in local nurseries. Hone also suggests asking nurseries to supply more native plants.