Nationwide declines in honeybees have focused attention on protecting native bees. One of the gardens featured on the upcoming Going Native Garden Tour demonstrates easy ways to encourage native bees and other beneficial insects.
The Troetschler Garden is the only Los Altos garden on the tour, which will feature more than 40 gardens in Santa Clara and San Mateo counties. Registration is free at www.GoingNativeGardenTour.org before noon on April 28 or until the tour reaches capacity, whichever comes first. The tour will be 10 am to 4 pm on Sunday, April 29, 2007.
“Bumblebees love California poppies,” Ruth Troetschler told me as we walked around her garden last month. Carpenter bees are partial to California fuchsia as well as other hummingbird flowers, she said. The native buckwheats under her fruit trees lure native bees as well as tiny beneficial wasps that prey on other insects.
Ruth pointed out a couple different beelike syrphid flies, which eat other insects, happily feasting on the stunning blue ceanothus flowers.
Keeping part of the garden wild and letting some plants go to seed is a good way to encourage native pollinators, she said. Flowers in the parsley, mint, phacelia, and daisy families are especially attractive to beneficial insects.
A healthy population of beneficial insects, in turn, helps to eliminate the need for toxic pesticides, which are lethal to plant-munchers and beneficials alike.
Native bees don't live in hives and don't produce honey, but they do pollinate about a third of the fruit, vegetable, and nut crops, according to UC-Berkeley entomologist Gordon Frankie. Unlike honeybees, which wait for sunny days, native bees will also work in cooler temperatures and in light rain.
Of 1600 species of California native bees, about 80 species are found in the Bay Area. Most of these build nests in the ground, which is why the Troetschler garden has a small area of bare unplanted ground. “Some bees like to dig,” Ruth said.
To provide homes for mason and some other wild bees, homeowners can make nesting boxes by drilling holes in a block of pine. The Troetschlers have placed their bee block under the eaves on the south wall of the house where the air is quiet, without any rustling tree leaves, and they clean the bee block every year.
To keep the bees and beneficials in your garden, make sure something is in bloom at least from late winter to late fall. In Ruth's garden, manzanita is the first to bloom, followed by ceanothus, sulfur and red buckwheats, and California fuchsia. She recently planted a blue elderberry to provide flowers for insects, followed by berries for birds.
Though bees are said to prefer yellows and blues, plant a variety of flower forms and colors. Clusters of each kind of flower attract more bees than single flowers scattered through the garden, Frankie found. Having at least 10 different clusters of flowers attracted large numbers of bees as well.
© 2007 Tanya Kucak