Pollinator Garden Tips

| Colorado Native Plants, Maintenance

by Jenifer Health

 In my reading and experience I’ve come across several ways to boost the value of my yard for pollinators. This article provides my favorite tips and tricks to enhance the value of your pollinator garden.  

Gardens that help pollinators are very important ecologically. Even a small space, like an apartment patio, balcony or deck, can contribute meaningfully to the survival of pollinators, as individuals and as a species. Together, we can saturate our communities with habitat for pollinators. This article focuses on invertebrate (insect) pollinators, including (but not limited to) butterflies, moths and native bees. (Honeybees, which are from Europe, will benefit as well, but are not indigenous to our continent and not the direct subject of this article).

Depending on the species, pollinators need pollen (protein source), nectar (energy source), water, larval host plants, sunlight and shelter to thrive. (The June 2020 issue of Wild Ones Front Range Chapter newsletter includes information about larval host plants.)  

Pollinators are animals that evolved alongside flowering plants. Some flowering plants are pollinated by wind, but many have evolved to attract and support animals that carry pollen from blossom to blossom and plant to plant for them, resulting in potential seed to create a next generation of the plant. Successful pollination (whether through pollinating animals, human intervention, or wind) is an absolute requirement for survival of the plant species. Plants encourage pollinators to visit them in many ways, including coloration (often at wavelengths of light that humans cannot see), scent, nutritional value of nectar or pollen, and providing nesting materials for animals. Even a single, high-quality pollinator-supporting plant in a pot can help an insect by providing sustenance along the insect’s path. One good pollinator plant is better than none; more good pollinator plants are better than fewer. 

1.  Leave the leaves. This tip is worthy to be first on the list, both because it is timely (it’s Fall!) and because of the huge and locally-devastating impact of not following this tip. “Leave the leaves” is a movement championed by the Xerces Society (an authority on insects) and many other organizations.  

Most butterflies and moths overwinter in the landscape as an egg, caterpillar, chrysalis or adult. They need leaf litter over the winter as protection. Many insects and their larva have evolved to resemble leaves, blending in for protection from predators. If we collect leaves (rake, scoop, blow, shred) from gardens, we are likely to unintentionally also remove and destroy the next generation of these insects, or to make them vulnerable to cold and predation.   

Many native bees (as distinct from the European honeybee) nest underground at a shallow depth. These insects need leaf litter as insulation to protect them from freezing temperatures.  

Countless other insects (many of them serving as food for birds and other wildlife) live in leaf litter and could be destroyed when we do Fall leaf cleanup.

Asclepias tuberosa and Monarda fistulosa in bloom
Photo by Lisa Olsen
Asclepias tuberosa and Monarda fistulosa 

In addition, leaves benefit you and your garden by building up healthy soil, retaining water (always important in our dry climate), and suppressing weeds. If you want to make a single change this Fall that will provide big benefit to pollinators, then, please, leave the leaves.  If you feel compelled to clean up the leaves come Spring, please wait until late Spring/early Summer after the insects have emerged.

2.  Minimize your Fall cleanup. For many traditional gardeners, Fall leaf cleanup is just the beginning. It is also common to cut down the perennials in the garden in Fall, including discarding seeds and stalks. Please don’t.

Especially if you have native plants, consider collecting the seed so that you (or your neighbors) can further enhance the habitat in your community by growing native pollinator-friendly plants inexpensively from seed. Helping to make pollinator gardening friendly to the family budget could significantly increase the size, quality and frequency of pollinator habitat in your neighborhood.  

In addition to bees that nest in shallow soil (mentioned above), other types of native bees nest and lay eggs in hollow stems or flower stalks. If we clean those up in the Fall, we eliminate all of the pollinators and eggs/pollinators-to-be(e) that are inside of those stalks. Let the plants stay where they stand (or have fallen) over winter. It adds “winter interest” to your garden and leaves shelter in place for insects that otherwise will die.

When you do clean up the garden in Spring, leave hollow stems and stalks until late May, when it will have been warm enough for long enough for the eggs to have hatched.  (I sometimes cut stems down earlier in Spring, then leave large piles of hollow stems/stalks scattered in sunny parts of my yard until June. That way I can complete the cleanup labor before it’s time to shift to planting.)

Echinacea purpurea (Purple Coneflower),
Campanula rotundifolia (Harebells), and
Callirhoe involucrata (Winecups)
photo by Jenifer Heath
Echinacea purpurea (Purple Coneflower),
Campanula rotundifolia (Harebells), and
Callirhoe involucrata (Winecups)

3. Native is better. When selecting plants for your garden, keep in mind that the more locally or regionally native plants you include, the better for the native bees and butterflies that co-evolved with those native plants. And take the time, before you buy plants, to think about what level of “native” you want to maintain. There is evidence that, at least in some cases, straight species are more nutritionally valuable and more accessible to native bees than named cultivars of native plants; many cultivars have been bred and selected for aesthetic qualities such as double petal forms, which makes pollen and nectar less readily available for pollinators.  

Staff at some garden centers will tell you that all Penstemons, for example, are native (not true, as many Penstemons in the horticulture trade are hybrids). While it is true that Penstemons are endemic to North America and are concentrated in the Southwest, there are many species of Penstemon that are native specifically to the Front Range. On the most practical of levels, a plant that is native to THIS AREA (as opposed to native to some other part of the country) will be better suited to our growing conditions, including our sunny dry summers and cold winters. In fact, after hailstorms, when my trees and my neighbors’ gardens are looking dismally torn up, my native plants just take it in stride and thrive. I have also found this to be true of early and late freezes – I never have to worry about covering my native plants or which plants will die from the cold.  

Solidago (Goldenrod) and Asters blooming
photo by Jenifer Heath
Solidago (Goldenrod) and Asters

More importantly, native plants are useful to our native insects. That’s not to say that you cannot also grow the azaleas you loved back home as a child (although they really don’t do very well here, so I encourage you to ditch the azaleas!), but rather I encourage you to have at least a few plants that provide habitat for specialist insects (those insects that are limited in terms of food sources or host plants for larva). You should take the lead and the responsibility for finding true native plants. Look at the scientific names of plants (not the common names) to identify the true natives. Wild Ones Front Range Chapter and the Colorado Native Plant Society are both good starting points for resources.  

In some cases, if you want a specific type of native plant, you may need to go to a more specialized nursery (like Harlequin’s Gardens in Boulder or High Plains Environmental Center in Loveland) or order seed, plants, or bare roots online (like at Prairie Moon or, if you look carefully at plant names, High Country Gardens). You can get high-quality native plants online if necessary (but supporting our local resources is a high priority).  

4. Build a sod farm and/or maintain bare soil.  Many of our native bees live underground, but here on the Front Range we often have clay soil, and we often cover the soil in our gardens with mulch. To help those ground-dwelling bees find shelter, at the very least it helps to provide patches of soil in sunny areas that are not covered with mulch or plants. This allows those bees access to potential shelter (holes in the ground). But it can be tough for a bee to dig a hole in clayey soil. If your garden includes pre-existing holes dug by other animals, some bees may use those for shelter, so consider leaving them as is.  

Alternatively, if you are feeling adventurous (and especially if you are removing sod) try building a sod farm. A sod farm is a small pile of sod you have removed, or just extra loose dirt from planting holes, maybe with a bit of structure like small branches scattered throughout. Simply pile the sod in a stack, root side to root side and grass side to grass side. This can provide easy access for the bees, as well as shelter and some insulation from the cold.  

5. Include plants with fuzz.  Some of our native (and one non-native) bee species collect the fuzz or hairs from plant leaves to line their nests. Named for this behavior, these bees are known as Wool Carder Bees (Anthidium sp.). Male European Wool Carder Bees (Anthidium manicatum) will aggressively defend their territory; to thwart that behavior it may be prudent to plant a few patches of plants with fuzzy leaves rather than one solid block. Wool Carder Bees show a preference for the extremely fuzzy non-native Lamb’s Ear, but are known to visit other fuzzy species, including the invasive Common Mullein (Verbascum thapsus). Desirable native plants with fuzzy leaves include Black-Eyed Susan (Rudbeckia hirta; avoid named cultivars); it grows easily from seed, has loads of bright yellow blossoms and a fairly long bloom season, and are flexible about how much sun they need. Other natives, like Coneflowers (Echinacea sp.), Sunflowers (Helianthus sp., including the native perennial Maximillian Sunflower), and Hoary Vervain (Verbena stricta) have noticeable hairs or fuzz. [Our native Milkweeds (Asclepias sp.), while not fuzzy, produce loads of seeds that are attached to fluffy tufts that carry the seeds aloft on the wind. Birds will use that fluff to line their nests in the Spring. If you are collecting Milkweed seeds in the Fall, save the fluff and store it over the winter to put out for the birds during the Spring nesting season.]

6. Create color or scent targets. Planting species in blocks of roughly 9 square-feet creates an eye-impactful swath of color during bloom season for humans. More importantly, it  creates a target of color for insects (probably colors that we can’t even see) and scent that can attract and nourish pollinators. These “targets” are sensed by migrating butterflies and can signal them to come down to your neighborhood for food. Anecdotally, the first year that my first target area bloomed, all my nearby neighbors reported more butterflies than in prior years.  

In addition, some bees will spend a whole day foraging from a single type of plant. If that type of plant is scattered throughout your garden or your neighborhood, that bee will expend much more energy finding food than if all the plants had been planted together. This is not to say that all of your perennials need to be planted in large groupings, but some should be.    

7. Provide blossoms throughout the Spring/Summer/Fall seasons. Different pollinators visit our area at different times of the year. Some are here during a migratory season, some are here briefly because they have very short lifespans, and some are here all season long. In every case, in every timeframe, we must provide sustenance. Otherwise an insect, or a cohort of insects, could die.

Notice whether there are times when there are no new blooms in your garden and find a plant to fill that time gap. You can research bloom times for potential additional plants – there are many resources online. I won’t lie; it’s tough to find much that is native and blooms really early (March/April) or really late (carrying into October). That’s when I supplement with non-natives, such as sedum “Autumn Joy,” which is the latest bloomer in my garden and loved by bees (or maybe it looks like they love it because they have no other sources of nectar that late?). For very early season, I use non-native Pasque Flowers (Pulsatilla vulgaris; I have the native P. patens, too, but it’s hard to get enough), Basket of Gold (Aurinia saxatilis), and early Bugleweed (Ajuga sp.). But for me, Prairie Smoke (Geum triflorum) comes way too late for my first cohort of pollinators. For some, our native Solidago (goldenrod) blooms late, many years it blooms so late it gets nabbed by frost. And Rabbitbrush (Ericameria sp.) is another good native option for late-season bloom.  

8. Provide water for your pollinators. Pollinating insects and birds need water. We all know about bird baths as a source of water for birds. Well, there’s a similar concept for bees: find a shallow dish, place stones or gravel above your intended water level so the bees will have a place to land, approach the water, stand, and won’t drown, and keep it filled with fresh water throughout the garden season.  

Butterflies (and some other insects) like (or need) to hang out around puddles of water in soil (probably NOT amended soil, but natural soil). One explanation for this is that they may be seeking out salts or other nutrients that move from the soil (or from decaying plants or carrion) into the water. You can find ‘how to’ instructions for making a puddling station for butterflies, but in my view, because we aren’t exactly certain of the purpose of puddling, we cannot be sure we’d be reproducing what they need, so why not take the easier path. Find an area of cleared dirt in your garden, preferably in the sun, create a slight depression in that dirt/soil (with a tool if necessary, but you might also be able to compress the soil with your feet), and fill it with water regularly throughout the season to keep it damp.  

Remember: It’s not all on you to save every pollinator, and no garden needs to follow every tip. Anything that you do will help.  Many of us are working towards Doug Tallamy’s goal of creating a “homegrown national park” by transforming bits and pieces of lawn, garden, rock outcrop, wall, fence, balcony, and patio pot area, throughout our rural, suburban and urban neighborhoods to native landscaping. [See Bringing Nature Home

  • Do your part: even a single pot, or a small patch in your corner of the world will provide better habitat for our native insects. That is a win for us all!  
  • If you don’t have a yard, balcony, patio, etc., volunteer at a community garden or with your city’s parks system to plant, weed, or water their pollinator gardens.
  • Consider coordinating with your neighbors to be sure that, between all of you, there is a variety of native host plants for larva, plants with fuzz or hairs, and targets blooming throughout the seasons.  
  • Take a bigger step and talk with your neighbors about planting garden areas that connect from house to park to office complex.  
  • Go further still or take a different path by not deadheading post-bloom, but instead allow the seed to mature. You can either collect and share the seed or let the plants re-seed naturally and share the baby plants next year. They are easy to dig up from your garden and plant in the garden of a neighbor or friend. (Be sure to leave seed on the plant for birds and other animals to eat in Fall/Winter/early Spring.)
  • You can harness the power of social media to find like-minded folks. You can post on Nextdoor when you have plants to share, thus contributing to native pollinator habitat in yards for blocks or even miles around.  

Need help getting started? Resource Central in Boulder sells sets of locally grown perennials with the intention of reducing water use and replacing lawns, bit by bit. Some of these are designed for pollinators and some include native plants (we at Wild Ones Front Range Chapter would really like them to be ALL native plants, but currently, they are not). A “Garden In A Box” is ordered in advance online and delivered, usually, to central locations throughout the Front Range for pick up. Some public water providers subsidize the purchase of these gardens.  

This list of tips is, of course, not comprehensive and flows from my own experience, what I’ve read, and what I’ve learned from classes and conversations. Here are a few resources that I especially like: 

Curious to learn more about transforming your garden into a habitat with Colorado native wildflowers, grasses, shrubs, and trees? Check out our native gardening toolkit, register for an upcoming event, subscribe to our newsletter, and/or become a member – if you’re not one already!