Like to eat? Thank a bee! Join us at the Haven on June 19 to celebrate National Pollinator Week. Our open house will take place from 5:30 to 7:00pm. Visitors will be able to:
- View an observation honey bee hive. Get a glimpse inside the hive to watch the queen lay eggs and the workers tend to the young bees and make honey.
- Observe our many bees "in action" working plants in the garden to collect pollen and nectar. Common bees seen in June include bumble bees, carpenter bees, honey bees, leafcutter bees, and sweat bees.
- Check out our lowest-water use bee plants to get ideas for your own water-wise bee garden.
- Taste and buy honey from the Honey and Pollination Center. A portion of the proceeds support bee research at UC Davis.
- Buy native bee houses for your garden. All proceeds support the Haven.
“How many plants do I need?” “How should I space my plants?” are two of the common questions we hear at the Honey Bee Haven when visitors ask about designing their bee gardens. Among the factors ecologists use to evaluate how bees use a floral resource are patch size, floral diversity, and floral density.
Patch size is the area covered by the desired resource (flowering plants) in a habitat that is fragmented. Floral diversity is the number of different species of flowering plants in an area, while floral density is the number of flowering plants in an area.
For honey bees, patch size is key. The scout bees return to the hive and direct their sisters to a good resource. Honey bees are efficient foragers that will visit many flowers on one plant until they have a full load of pollen or nectar. By grouping all plants of a species into a singe patch rather than spreading them around the garden you help honey bees maximize the value of each trip to and from the hive. There is no hard and fast rule for a minimum patch size, although three feet square is an area often recommended by bee biologists.
Bumble bees, on the other hand, tend to move quickly from plant to plant. So large patches of one plant species are less important than dense patches with a diversity of flowering plants.
At the Haven we have examples of both planting styles.
Getting back to the questions posed at the beginning of the post: rather than worrying that you might not have a large enough garden or be able to provide the right mix of plants, just do it! Choose plants that will provide flowers for as much of the year as possible, with as much of the garden as you can planted with flowers. In the Davis area, bees are active year round so the Haven always has something in bloom. If the garden does include turf areas, which don't provide bee forage or habitat, try to plant your flowers so that they are in a continuous patch.
Good horticultural practices are important to the success of any garden. In bee gardens, though, we need to do things a bit differently, as some common practices may not be best for the bees. When most of us think of bees and pollination the managed European honey bee, Apis mellifera, comes to mind. But beyond the honey bee are over 1500 species of bees native to California, many of which provide essential pollination services in both wild and agricultural settings. About 70% of these wild bees live in underground nests. This includes the social bumble bees and solitary bees like the long-horned bees (Melissodes spp.), digger bees (Anthophora spp.) and sunflower bees (Svastra obliqua) that are common in urban gardens.
Three important practices that should be adjusted to accommodate ground-nesting bee habitat are mulching, tillage, and sanitation.
Mulch has many benefits in the garden. It retains soil moisture, can protect against soil temperature extremes, and provides valuable habitat for arthropod predators such as ground beetles (family Carabidae). Ground-nesting bees need bare soil to create their nests, however, so bee gardeners should leave some ground uncovered. Visitors to the Honey Bee Haven will notice that the garden has many areas of sparsely-laid mulch to accomplish this. Turf-covered areas are not used for nesting.
Ground-nesting bees have soil preferences that vary by species. This is an area in which very little research has been done, but we do know that undisturbed soil is essential. Tilling the garden destroys underground bee nests and disrupts abandoned rodent burrows that are important bumble bee nesting sites.
Finally, while sanitation is an essential tactic in garden pest management, it’s important to not be too neat. Small clumps of grass or weeds or debris left under shrubs can protect the bumble bee queen as she overwinters in her nest below. Garden visitors will see that we leave some weed growth on the garden edges to provide this type of habitat.