July 2024 Plant Availability

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Greetings,

We hope your summer solstice was ‘a buzz’ with beauty and light, as ours was here at the nursery. It’s been truly remarkable to see such diversity of native bees this spring and summer, taking advantage of all of the glorious native blooms throughout our retail tables and garden spaces. In the brief moments without sounds from traffic along Canal Blvd. and the trains in the train yard across the way, we can literally hear the nursery buzzing from all of the bee activity!

Have you ever wondered why bees buzz?

If, like us, you assumed it was because of the vibration of their wings, you are partially correct– bees definitely make a buzzing sound as they fly…but have you ever noticed a bee buzzing when its wings aren’t moving? We recently have, and our curiosity led us to the fascinating adaptation of ‘buzz pollination.’ Let’s get into it!

What is ‘Buzz Pollination’ / Sonication?

Buzz pollination (also called “Sonication”) is simply a method of pollination whereby bumblebees produce vibrations that allow them to shake more pollen loose for the taking than other pollination methods are able to do. Upon visiting a flower, a bee lands and grabs onto the base of the anthers (the part of a flower that produces and contains pollen) with its mandibles (mouth parts), curling its body around the anthers so that its thorax (midsection) surrounds the pollen-bearing part. Once securely positioned on the flower, the bee halts the beating of its wings and begins to rapidly contract its thorax muscles, separate from its flight mechanisms. The resulting vibrations from the bee’s thorax muscle contractions are transmitted through the bee’s head, mandible, and body, to the anthers of the flower. As the vibrations resonate through the anthers, the pollen grains within become excited and expelled onto the bee’s body.

Which pollinators perform buzz pollination?

Researchers have found that the ability to pollinate by way of sonication has been observed across over 50 genera of bees and even 1 hover fly! Perhaps most notably though, honey bees (Apis mellifera) are unable to use this ‘buzz’ method of pollination. If you’ve ever heard that native bees are more efficient pollinators than honey bees, this is one of the big reasons why.

Why is buzz pollination important?

There are approximately 15,000 – 20,000 species of plants across 65 genera with flowers that require buzz pollination, since their flowers only release pollen through small openings (pores/slits) in their anthers’ tips. It is hypothesized that flowers evolved this morphology as a means of reducing competition among pollinators– when fewer pollinators are able to effectively get pollen from a particular type of flower, it increases the likelihood that some of that collected pollen will end up in another flower of the same kind, resulting in successful pollination for that plant species. It also protects precious pollen from pollen theft (when an animal collects or eats pollen with little to no pollination provided in return; usually a product of mismatched morphology between a plant and an animal). Buzz pollination is crucial for a variety of really important food crops such as tomatoes, peaches, potatoes, and blueberries. Better quality pollination, whereby more pollen grains are transferred from the male to the female parts of a flower affects the quality of food produced, such as melons, apples, and even strawberries–which don’t exclusively need to be buzz pollinated, but are much better quality if they are! Since honey bees are unable to perform buzz pollination, this is a clear indication that native bees have huge ramifications on our food production systems.

If you’d like to witness buzz pollination in action and support the native bees that perform it with rich pollen sources in your garden, here are some of the native plants species we have in stock this month that are adapted for buzz pollination 🙂

Bluewitch Nightshade

Solanum umbelliferum

Available in D-16 pots for $7.30

Bluewitch Nightshade is a tough perennial sub-shrub that grows up to 2-3 ft. tall and wide.
The 1-inch, bright blue-purple flowers bloom most of the year and are followed by bright green berries that turn a deep purpley-black when ripe (do NOT eat them! – all parts of this plant are toxic to humans and some animals).
Grows in both rocky and clay soils, does well in containers, and will stay green, leafed out, and blooming with a little summer water. It’ll also thrive on neglect, going summer deciduous to survive.
They are a lovely showy bloom for a sunny spot in a garden, and do well in containers, too!
Pairs well with annual wildflowers, monkeyflowers, sagebrush, and asters.
A great choice for bee gardens as the bright yellow centers of the flowers provide a plethora of pollen with the right ‘vibes’ 😉

American Nightshade

Solanum americanum

Available in D-16 pots for $1.93 (75% off) – $8.50

American black nightshade is an annual or short lived perennial herb and grows about 2 – 5 ft. tall, favors open spaces in woodlands, and often disturbed, wetland-riparian areas. Widely distributed across the Americas, and used medicinally internationally!
The delicate, parachute-like drooping white and yellow flowers are followed by shiny dark blue berries.
Caution–all parts of the plant are toxic, especially unripe fruit, so leave the fruit for the birds!
American black nightshade is one of the most widely spread and morphologically variable Solanum species–best for restoration and larger-scale plantings, where it has room to reseed and spread!

‘Carmel Sur’ Manzanita

Arctostaphylos edmundsii ‘Carmel Sur’

Available in D-40 pots for $10.90

This popular Manzanita cultivar, ‘Carmel Sur’ (formerly ‘Emerald Carpet’) is valued for its dense, petite, deep green foliage and rapid spreading growth, up to two feet a year. It will grow to about 1 ft. tall and 6 ft. wide in the form of mounds or patchy mats in sandy soils. Space 4 ft. apart.
The small, urn-shaped flowers are white to pale pink, favored by native bees and butterflies, and will produce shiny red-brown drupe fruit.
Carmel Sur is an excellent choice for a groundcover and makes a beautiful addition to coastal gardens and habitat gardens.
Since this is a hybrid of two coastal species, it is not very tolerant of heavy clay, but it does well in most other soil types.
A little supplemental summer water is necessary farther inland from the coast, and it prefers afternoon shade. Avoid direct salt spray if planting along the coast!

California huckleberry

Vaccinium ovatum

Available in D-40 pots for $10.90

A slow growing, evergreen shrub that grows to 2 – 3 ft. in the sun and up to 12 ft. tall and 10 ft. wide in the shade!
It prefers well-drained, humus-rich soils, and is native to low-elevation forests of Western North America, especially woodland edges and openings.
The small, ovate, evergreen foliage looks good year round, has small pinkish urn-shaped flowers March – May, followed by edible glossy, blackish-purple berries that are favored by birds and small mammals.
In a partial shade garden, the shrubs are a beautiful backdrop for mixed borders. In a full shade garden, grow it as a tall evergreen hedge. In a full sun garden, it will produce more berries but it will not grow as tall as it will in the shade garden. Also does well in containers!
A valuable food for numerous native peoples of western North America, huckleberries can be eaten fresh, dried, stewed, canned, made into pies, mixed with oil, or dried into cakes.

Mock Heather

Ericameria ericoides

Available in D-40 pots for $2.48

Mock heather (also called California goldenbush) is a small, mounding, evergreen shrub that grows to about 3 ft. tall and 3 – 4 ft. wide.
Deer resistant, fast growing, and tolerant of saline soil, this sturdy shrub is sure to stand up to wind, water and browsing!
The bright golden-yellow colored flowers blanket the densely leafed plant from late summer into fall, providing late season color, pollen and nectar to hungry pollinators!
Native to sand dunes, from just north of the Bay Area to the Los Angeles area, Mock heather will thrive in seaside conditions, and shapes up well with light winter pruning.

Leopard Lily

Lillium pardalinum

Available in 4”, D-16, and 1-gallon containers for $7.30-$14.50

This towering member of the lily family is very elegant, and pleasing to the eye. Its 3 – 8 ft. tall stalks bear up to 30 pendant blossoms in late spring or summer. Then, like most bulbs, they go winter dormant.
The striking orange blooms have a base of scarlet with small maroon speckles sprinkled across the petals, which are a bright show against delicate chartreuse stems.
Leopard lily is also a nectar plant for large butterflies such as the two-tailed tiger swallowtail, monarch and admirals.
Plant with ferns, coral bells, western azaleas, or any other moisture loving shrubs in damp areas of a partially shady garden.

Douglas Iris

Iris douglasiana

Available in 1-gallon containers for $14.50

Douglas Iris is an herbaceous perennial that grows 1 – 2 ft. tall and will spread and self sow, filling in a cottage shade garden beautifully.
Useful in several contexts–does well in dry shade under oaks, broad container platings, rock gardens, slopes, massing together to form dense clumps.
Pairs well with companion plants such as woodland strawberry and yerba buena.
The large dark purple flowers (occasionally white, rarely yellow) are seen in late winter through spring, and can be deadheaded in the summer for a tidy look.
Blooms are attractive to native bees and other insects, and provide nectar for hummingbirds!

Research & Resources

De Luca, Paul A, and Mario Vallejo-Marín. “What’s the “Buzz” About? The Ecology and

Evolutionary Significance of Buzz-Pollination.” Current Opinion in Plant Biology, vol. 16, no. 4, Aug. 2013, pp. 429–435, https://doi.org/10.1016/j.pbi.2013.05.002. Accessed 24 June 2024.

Kubey, Elizabeth. “Small Wonders: The Plight and Promise of California’s Native Bees.”

California Native Plant Society, 25 June 2021, www.cnps.org/flora-magazine/small-wonders-the-plight-and-promise-of-californias-native-bees-23883.

Look, Deep. “This Vibrating Bumblebee Unlocks a Flower’s Hidden Treasure | Deep

Look.” YouTube, 19 July 2016, www.youtube.com/watch?v=SZrTndD1H10.

“Pollen Specialist Bees of the Western United States.” Jarrodfowler.com,

jarrodfowler.com/pollen_specialist.html. Accessed 24 June 2024.

Vance, Erik. “Native Bees Often Better Pollinators than Honey Bee | Research UC

Berkeley.” Vcresearch.berkeley.edu, 14 Nov. 2011, vcresearch.berkeley.edu/news/native-bees-often-better-pollinators-honey-bee.

‘Buzz’ On and ‘Bee’ Well from all of us at the Watershed Nursery!

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