Put your bee home up in March or early April! This will offer prime nesting sites for solitary bees for laying their eggs.
(Several excerpts from the UC California Agriculture Urban Bee Study)
California has 1600 native species of bees! Santa Barbara County has 5 families, 19 genera, 67 species! Solitary bees deserve a sweet space in our gardens and in our hearts!
Plant what they eat!
In an urban bee study by UC California Agriculture, California plants that got high counts of visits were easily accessible plants, cosmos (Cosmos spp.), lavender (Lavandula spp.) and catnip mint (Nepeta spp.), partly due to their long flowering periods. Of native bees throughout California, the two most attractive plant families to bees were Asteraceae (which provide pollen and nectar) and Lamiaceae (which provide nectar).
Bumble bees (Bombus spp.), small sweat bees (Halictidae) and honey bees all enjoy California Poppy. Honey bees and large carpenter bees (Xylocopa spp.) love palo verde (parkinsonia aculeata), wisteria (Wisteria sinensis) and autumn sage (Salvia greggii/microphylla/cvs.). Digger bees (Anthophora edwardsii) forage faithfully on manzanita flowers (Arctostaphylos).
Blanket flower (Gaillardia x grandiflora) and sunflower (Heianthus an-nuus) attract long-horn bees (Melissodes spp.) and honey bees.
Already you have learned the names of some of your bees, plus what they like to dine on! Plant different kinds of plants to bring more bee diversity!
Some 60 to 80 species were identified in each city where study counts were done; the ultra-green sweat bee (Agapostemon texanus) was among the most common. Top, a female on bidens (Bidens ferulifolia); below, a male on sea daisy (Erigeron glaucus). Many bees lived here before urbanization; they and others have adapted. For example, honey bees (Apis mellifera), alfalfa leafcutting bees (Megachile ro-tundata), Megachile apicalis and Hylaeus punctatus. Megachile ro-tundata is a commercially important leafcutting bee. Honey bees, the most common yellow-faced bumble bee (Bombus vosnesenskii), the large carpenter bee (Xylocopa tabaniformis orpifex) and the ultra-green sweat bee (Agapostemon texanus) live throughout California.
Severely wet winters and springs are hard on bees. They prefer warm, sunny mornings with little or no wind.
And, they need safe living quarters!
Bee hotels, a pollinator’s paradise, are small to large, simple to elaborate! Pollinators’ housing needs are hugely diverse! Bare soil, hollow twigs, big holes in trees, little holes of only a certain depth.
Solitary (nonsocial) bees will nest in a variety of substrates in urban gardens. The digger bee (Anthophora edwardsii) nests in bare dirt. About 70% of solitary bees nest in the ground! Solitary means a male and a female bee mate, and the female constructs a nest and lays an egg in each single cell she creates, with 3 to 10 cells per nest depending on space; there is no hive, division of labor or social structure as in the social honey bees and bumble bees.
Many of these solitary bees prefer to construct their nests in soils with specific characteristics, such as composition, texture, compaction, slope and exposure. Nesting habitat can be provided for these bees in gardens by leaving bare soil and providing areas of specially prepared soil, from sand to heavy clay to adobe blocks. Make a Miner bee nest! Excessive mulching with wood chips will greatly discourage ground-nesting bees, which need bare soil or a thin layer of natural leaf litter.
If you see soil like this, DO NOT WALK ON IT, rope it off so others don’t either. The Miner bee nests in colonies of separate tunnels excavated into hard clay. Females construct the nest, softening the hard clay with regurgitated water and removing clay particles with their mandibles.
Other bees nest in pre-existing cavities. Honey bees nest in large tree cavities, underground and in human structures such as the spaces between walls, chimneys and water-meter boxes. Bumble bees commonly nest in abandoned rodent burrows and sometimes in bird nest boxes. Most cavity-nesting solitary bees such as Hylaeus (Colletidae), and most leafcutting bees and mason bees (Osmia [Megachilidae]) prefer beetle burrows in wood or hollow plant stems. Nest habitats for these bees can be supplemented by drilling holes of various diameters (especially 3/16 to 5/16 inches) in scrap lumber or fence posts, or by making and setting out special wooden domiciles in the garden. Once occupied by bees, these cavities must be protected from sun and water exposure until the following year, when adult bees emerge to start new generations. Neglecting to protect drilled cavities occupied by bees can lead to bee mortality. Some people tuck them back in old mailboxes. You will find some excellent bee care tips at Wings in Flight!
Hollow twigs, bamboo, various size holes drilled in logs and 4X4s.
Left, sealed nursery chambers. Right, adult emerging from nest.
Large carpenter bees (Xylocopa) excavate their nest tunnels in soft wood such as redwood arbors or fences, and small carpenter bees (Ceratina) use pithy stems such as elderberry or old sunflower stalks. Partitions between the brood cells are usually composed of bits of excavated material.
How good does it get?! This is an epic weather protected, farm-size community for solitary bees that opens to both sides!
How about this Pollinator Condo?! [It needs weather protection….] Lower larger holes are for Bumblebees. Bumblebees will also nest in old bird houses.
You can buy bee homes, even bee home making kits, but if you are even a little bit crafty, why not make one?! It could be big, it could be on a post, or small and decorated hung among the tomatoes! The bees will love you!