Planting for Pollinators - Spanning the Summer Dearth

March 6, 2018

by Bill MacElroy

A key mission of the Sonoma County Beekeepers’ Association is to encourage people to plant for our pollinators—including not only for our precious honey bees but also many other native species of bees and bumblebees.

Cultivation and landscaping in Sonoma have changed the floral ecosystem in a way that causes long periods of time where not much food is available to the foragers.

In particular, toward the end of summer, most landscaping plants have stopped flowering. This is called the “summer dearth” and it can mean hard times for the pollinators who are getting ready for winter. As we inspect honey bee hives before the winter rains, a key indicator of colony health is the degree to which they have successfully put away “stores” of honey and pollen (bee bread).

In areas where nothing has bloomed for several months, we frequently see little to no critical supplies to keep the colony fed in the colder months.

One of the top reasons that colonies don’t survive through to spring is that they simply starve to death.

Few people realize that it takes more than 1.5 million flowers and 50,000 miles of bee flight to make one pound of honey. A normal colony in our Sonoma Mediterranean climate needs about 40 pounds of honey to comfortably winter-over—so that’s a LOT of work that the bees need to accomplish between spring (when there are lots of things blooming) and the time when the flowers are gone. Our job as gardening stewards of the land, is to make sure that period of time is as long as possible.

Over time, many wild plants that were “late bloomers” in Sonoma have been removed because they don’t fit with our notions of a well-kept lawn. These include dandelions, thistles, clovers and wild fennels. So when “planting for pollinators,” a very important aspect to your planning should be to include things that bloom in the July to October timeframe. If you have land that isn’t being used, consider letting the “weeds” bloom wild where there’s low risk of fire.

A few very good options for “spanning the dearth” include: borage, butterfly bush, fuchsias, continuous blooming roses, heather, lavender, mint, rosemary, oregano, sage, sunflowers, thyme, valerian, and yarrow. Many of these are naturals for an herb garden, so they not only feed the pollinators—they also feed you!

Many plants (borage, lavender, oregano, etc.) can be encouraged to blossom multiple times during the summer by cutting them back after the first bloom. Lavenders, in particular, will send up a hearty second set of bloom spikes in August if you cut them for fresh flowers in early June. Rosemary is also an important plant for pollinators because, in our climate, it blooms almost all year round.

There are many, many resources for information on planting for pollinators in Sonoma County. Here are several good links:

http://www.sonomabees.org/wp-content/uploads/2015/08/Plant4Bees_hand-out_v3.pdf

http://sonomamg.ucanr.edu/Top_Plants_for_Sonoma_County/

https://www.sunset.com/garden/flowers-plants/plants-pollination#plants-pollination_15

Dr. Bill MacElroy is a member of the Sonoma County Beekeepers’ Association and is the general manager of Monte-Bellaria, a West Sonoma County lavender farm.www.monte-bellaria.com