Navigate / search

How does your garden grow?

Remember those pollinator gardens we discussed back in January? Remember the plant lists for bees and the arguments about natives versus invasives? Well then, how is it going?

On this end, I’ve got good news and bad—tales that are amazing, funny, and disappointing. Here’s my report so far.

Siberian squill: I planted hundreds of Siberian squill bulbs in the fall of 2013 in the hopes of seeing blue pollen on my bees. Dozens of people told me it was invasive, that it would take over my entire property, that I would be sorry. But in spring of 2014 I was delighted with the flowers, the blue pollen pellets, the many native bees that came calling, and the dozens of photos I managed to get.

But this spring? Nothing. No plants (well, maybe five or six), no flowers, no blue. I was severely disappointed. So much for invasive. The lesson learned is that what is a sure-fire invasive nightmare in one ecosystem is a complete dud in the next. I wanted to be invaded but I was abandoned. Oh well.

Straw bale garden. I planted six straw bales this spring, four with potatoes and two with pollinator plants. Shortly after I planted, one reader told me he had tried it, found the straw field had been treated with herbicide, and all his plants died. I kept my fingers crossed, remembering that if it worked, I wouldn’t have to weed, deal with slugs, or water incessantly.

Apparently, I got lucky because my plants lived. But the slugs hadn’t read the bit about not liking straw, and every morning there are dozens of them at the salad bar munching away. Well, at least as many as can fit between all the wheat that sprouted from the top and sides of the bales.

All the articles I read said to use straw, not hay, so you don’t get seeds. I used wheat straw and got (not surprisingly) wheat—hairy masses of healthy, strong, stubborn wheat. I’ve spent more time pulling wheat seedlings than I ever would have spent pulling real weeds. Not only that, but between the wheat and the slugs, grew mushrooms—dozens of shapes and sizes and colors popped up through the top and out through the sides.

And then there’s the water. I read that the bales hold moisture so you can water less frequently. As it turns out, I have to water the bales twice for every time I water the rest of the garden. The bales seem wet enough, but the plant roots can’t seem to find it. Bummer.

Lemon Queen Sunflowers: At this time, the Lemon Queens (the sunflowers used by the Great Sunflower Project) seem to be doing fine. They are about three feet tall and look healthy—but this is my second batch. The first batch got picked out of the ground by Steller’s Jays, so I had to reorder the seeds and plant again. I started the second batch in the kitchen and held my breath when I finally transferred them to the garden. So far, so good.

Encap Honey Bee Mix: I planted this because I was curious. The bag says it contains mulch, fertilizer, seed and sparkling crystals that “swell and glisten when enough water has been applied.” So every day I water and look for sparkles. When the ground starts to float away, I stop, but still no sparkles. I’m getting plants from it, so I should be happy, right? But I want sparkles.

Last year’s perennials: Every year I plant more perennials, always looking for those plants that attract bees. Except for the Siberian squill, last year’s perennials are doing well. And here’s the best news: I saw a host of bee species this year I never saw before. Every year I think I’ve reached some kind of limit—an asymptote—but every year I see more and more different species. It is really true that if you plant flowers and hold the pesticides, you will enhance your wild bee population in short order.

In addition to several new-to-me Andrena bees, I’ve also spotted an Agapostemon, large leafcutters, Osmia aglaia, Bombus californicus, and a couple of species I haven’t yet identified. Is that cool or what?

My ceanothus bushes are as loud as my honey bee hives, but the sound comes not from honey bees but from scores of bumble bees. The blossoms are heavy with them, dipping and bobbing under their weight. The laburnums, highbush cranberry, and aronia have also been teaming with wild bees, while my honey bees have been distracted by maple, cascara, bitter cherry, and now blackberries.

One problem I didn’t see coming was my nesting tubes. They filled up early, so I purchased several more canisters in a hurry and they too were quickly filled. Next, I carefully removed the paper straws, stored them in a different container, and replenished the straws. When they filled, I had to do it again. The season is still young, so this exercise isn’t over. At least it’s a good problem to have.

Fall flowering perennials. I planted many new fall-flowering plants this year, mostly based on your recommendations in the plant lists. Yesterday, my bed of Autumn Joy sedum got undermined by a mole that managed to turn them all over, one-by-one, right down the row. I replanted them before the sun did too much damage (I hope). We’ll see.

So there you have it, the highlights and lowlights of my pollinator garden so far this year. So tell me about yours. What’s working and what’s not? What’s disappointing and what’s amazing in your bee garden today?


This male berry bee (Osmia aglaia) is taking a rest after a lot of, um, strenuous activity. © Rusty Burlew.

Are we raising extra-large mason bees?

Except for natural bamboo tubes, it seems that most commercial tunnels sold for pollinator housing have an inside diameter of about 7 to 8 mm for orchard mason bees (Osmia lignaria), 6 mm for blueberry bees (Osmia ribifloris), and 5 mm for both alfalfa leafcutting bees (Megachile rotundata) and raspberry bees (Osmia aglaia).

I don’t know where these numbers came from originally—and that is what makes me suspicious of them. Everyone who cites these measurements got them from someone else, who got them from someone else. Much like that statistic that claims one-third of our food is pollinated by bees, everyone says it but no one can confirm it.

All I know for sure is this: when I give my Osmia lignaria a variety of tunnel sizes, they pick ones that are smaller than the recommended sizes. For example, they always choose a 5 or 6 mm hole over the much larger 7 or 8 mm holes. The summer masons and leafcutters seem to prefer a hole smaller than the recommended 5 mm, generally choosing a 4 mm hole.

If you’ve been around honey bee keepers for a while, you know there is heated debate about the size of artificial foundation. On average, the cells in most foundation are quite a bit larger than the cells found in natural combs, and larger foundation produces larger bees. Many people, myself included, think that a natural cell size is best for overall honey bee health.

Now I’m wondering if we are creating artificially large Osmia and alfalfa leafcutting bees by providing housing that is a little bit wider than that found in nature. Furthermore, we know that wild species raised in artificial nests are falling victim to ever more diseases and parasites, just like honey bees. Are any of these ailments more apt to appear in larger bees raised in larger tunnels?

Just as an experiment, I purchased a pair of these: Kinsman Giant Solitary Bee Nester with 60 Tubes. The tubes inside are about 7 mm in diameter. Next I bought a supply of Paper Straws ranging from about 4.5 to 7 mm inside diameter. I made collars for the paper straws so they wouldn’t float around inside the larger tubes.

When that was done, I set the first Kinsman nest on top of another pollinator unit behind my house, just to get an idea of how to fasten them together. I went to get some hardware, but by the time I got back, the mason bees were already investigating the smaller holes. I decided it was too late to move it, so I just tied it on with survey tape. I will set out the second nest in about six weeks when the summer masons and leafcutters are flying.

My plan is to remove the cocoons in the fall and look for differences between those in large tubes vs those in smaller tubes: pollen mites, mummies, parasites, whatever I can find. This is by no means a controlled experiment, but just a look-see to decide if there is something to study in the future. I will keep you posted.


Some of the paper straws I used. They come in different diameters, but you have to read the fine print to find the info. I got different colors so I can easily tell the sizes apart.
I measured the straws and cut them to the right length for the nest.
I slit the tubes to make them easier to open later. They pop back into shape after they are cut.
I put the slit straws into larger ones so they maintain their size.
I used the cut pieces as collars for those with too much free space around the tube opening.
Here is a larger straw with a collar in place.
Here is a Kinsman nest being filled with straw inserts.
Within five minutes of putting it outside, the masons were inspecting it.

*This post contains affiliate links.

Pollinator walls, bee towers, and insect hotels

It seems that everyone is building for the bees these days, from private citizens, to transportation departments, to architectural design firms. The proliferation of bug structures, no matter how humble or how grand, indicates that humans are finally getting it: insects need a place to live too. As we cover more and more of the earth’s surface with buildings, roads, airports, and crops, it becomes vitally important to provide living quarters for the insects that serve us.

The structures are as varied as the insects that inhabit them. They may be smaller than a birdhouse or may cover the side of two-story building. They may be designed to attract bees, potter wasps, other pollinating insects, or even vertebrate pollinators like hummingbirds and bats. Some offer housing to non-pollinating beneficial insects such as ladybugs and lacewings. The options are endless and the designs are original and creative.

Germany seems to be the leader in bug structures, followed closely by Great Britain. Because those countries are small compared to places like Canada, the United States, and Australia, they were quick to realize the importance of coexisting with the beneficial insects and the need to provide shelter for them in the built environment. The insects use the habitat for shelter, safety, nesting, raising young, and finding food.

A feature that distinguishes walls, towers, and hotels from structures like mason bee condos or bumble bee nests is the wide variety of nesting choices. Pollinator walls may contain hollow reeds, wood with pre-drilled tunnels, cracked or drilled masonry, straw bundles, rolled corrugated board, clustered stones, or dry leaves. The “invertebrate habitat” shown below was built by the Cheshire Wildlife Trust. It contains many types of habitat and was built completely from recycled materials.

Invertebrate Habitat by Cheshire Wildlife Trust

The next photo shows the winner of the 2010 Beyond the Hive Competition in London. This “bug hotel” was built by Arup Associates and is designed to encourage many types of invertebrate inhabitants.

Insect hotel by Arup Associates.

If you decide to build your own habitat, here are some important issues:

  • The structure should be in an area sheltered from bright sun and high wind, such as close to a building or under a shady tree. If you hope to attract some native bees, at least past of the structure should be in the sun.
  • Insects need water, so a reliable supply such as a pond or creek should be nearby. Alternatively, you can provide an artificial source–just don’t let it run dry.
  • Many solitary bees and wasps need a source of mud.
  • The fill material should be varied in type (stones, masonry, dead leaves, reeds, wood, twigs) and have many little cracks and crannies, nooks and crevices.
  • The design must be structurally sound so it doesn’t topple from wind, rain, or snow. If you live in an earthquake zone, keep the structure low and wide instead of tall and narrow.

Structures don’t have to be large. The one shown below is small enough to become part of the garden. This was an entry in the Beyond the Hive competition by Helaba Landesbank Hessen-Thueringen.

Small but effective.

The possibilities for building insect habitat are endless and can satisfy the artist in you. So give it a try. If you like, send me a photo and I’ll post it here on my site.

Pollinator housing attached to a building. Photo by Wildbienen.


Wild pollinators cannot replace honey bees . . .

At least not in the way we’d like. In the past few years a flood of articles has heralded native pollinators as “saviors”—groups of selfless, tireless, seldom-seen gladiators that are going to step in and save our food supply once the honey bees die off.

This is a comforting thought, and perhaps one day native pollinators will shoulder the bulk of our pollination needs—but it won’t happen within our current system of agriculture. It can’t. Successful transition to native pollinators will require nothing short of a complete overall of our current farming system.

If you read about the biology and ecology of wild pollinators, you will see they can be very efficient in terms of the number of flowers pollinated per minute. So efficient, in fact, that you wonder why the heck we ever started using honey bees. But as you dig deeper, you will also see they have very different life cycles and habitat requirements.

Some native pollinators will forage only a few hundred yards from their homes while honey bees will easily cover a three-mile radius—even more if resources are scarce. Some native pollinators visit only one plant species, or several, while honey bees pollinate hundreds. Some native pollinators are active only a few weeks of the year while a honey bee colony will forage any time the weather permits. Most native pollinators live singly or in small groups while honey bees live in massive colonies. The list goes on.

In the “old days,” let’s say before the end of WWII, people who kept honey bees kept them for honey. And if you didn’t keep bees, you didn’t worry about pollination. In fact, no one paid any attention to pollinators because there was no shortage. A farmer planted a field, the pollinators did their thing, and a crop was harvested. Short-lived, picky pollinators weren’t a problem because there were hundreds of different kinds. There was always one or a dozen other species to pick up where the last one left off.

But the Green Revolution changed how we farm and, before long, there weren’t enough native pollinators to do the job. The fields were too big, the habitat was too scarce, and pesticides were everywhere. As farms got bigger and more mechanized, honey bees had to be trucked in along with other forms of migrant labor.

Even the people who are currently studying native pollinators concede that without significant changes, native bees might supplement—but not supplant—honey bees. Some experts estimate that up to 30% of the farmland would have to be converted to bee habitat. Hedgerows, borders, and habitat strips would have to be interspersed with crops. This reserved land would need to remain un-tilled and be planted with large numbers of flowering plants so that something was always in bloom.

Thing is, even with all those resources devoted to wild species, it might not be enough. We would have to change pesticide practices, stop poisoning roadside weeds, and eliminate larger-than-life fields. We would have to become stewards—rather than pillagers—of the land.

I wouldn’t want to discourage anyone from keeping a hive of honey bees or tacking a bee block to a fencepost. But even thousands of them won’t assure a future food supply. To do that we must change the way we farm—from endless rows of monoculture to GMOs to weed control—it all has to be fixed. Native pollinators can’t save us unless we save them first. Care of pollinators needs to be job one.


Bumble bee on ceoanthus.

Milkweed fairies due for a comeback

Make a wish, blow it free.

What kid in America didn’t grow up chasing milkweed fairies? The hairy white seeds floated, bobbled, and danced across the grass while the neighborhood children delighted in catching the elusive prize. Once caught, you cupped it in your hands, made a wish, and blew it free. It tumbled out on a summer breeze and drifted to wherever.

Kids? I still catch milkweed fairies and I’m plenty old enough to know better.

The problem is this—there just aren’t as many milkweed seeds floating around as there used to be. For some reason we like to see more “refined” perennials growing along our fences, roadsides and utility easements. But that’s a bias that’s hurting the pollinators—especially the milkweed butterflies such as the monarch.

The awe-inspiring monarch is completely dependent on milkweeds for survival. The larval stage eats the leaves of the milkweed and stores a portion of the poisonous sap in its tissues. This poison remains throughout the life cycle of the monarch, making it distasteful to predators. If we want to save the wondrous migrating monarchs, we have to save the milkweeds.

Milkweeds don’t deserve the “weed” part of their name. They are sturdy perennials that love the sun and can live in poor and rocky soils. Depending on the species, they grow from 2 to 6 feet high and make excellent low-maintenance border and landscape plants. The flowers come in an astonishing array of colors that includes white, green, pink, purple, and brilliant orange, and the seed pods make eye-catching dried arrangements.

The best part is that milkweeds attract not only monarchs but a panoply of pollinators including bees, other butterflies, and hummingbirds.

So put it on your list. Buy some milkweed seeds. The organizations below will provide free or low-cost milkweed seeds in a variety of colors that are especially attractive to monarchs. The sites contain useful planting and care instructions as well.

Go ahead. Plant them for the butterflies . . . plant them for the kids . . . plant them for the fairies. Then make a wish.


Milkweed seeds. Flickr photo by Muffet/liz west.