If your landscape goal is to have the perfect lawn, who is it for? Yourself? Your neighbors? If the answer is both, perhaps you should expand your definition of neighbors and rise to a different challenge: Try growing a perfect lawn for bees.
That means you’ll have to change your concept of a perfect lawn. Most people probably think a lawn should consist of a single type of grass that's manicured and maintained to look like a golf course. And why not? It’s a lawn they can love and their neighbors will admire. It’s a look millions of Americans strive for.
According to a 2015 study by the National Gardening Association, 49 percent of all U.S. households, or 59 million households, participated in lawn care in 2015. The study also found that lawn care retail sales increased to $10.9 billion in 2015 and average household spending on lawn care in 2015 increased to $201.
But all the time, money and effort Americans spend creating a perfect lawn for themselves isn't so perfect for bees. In reality, it’s a food desert. Luckily for homeowners and bees, there’s a happy middle ground, one that can provide an attractive look for homeowners as well as foraging opportunities for bees. It’s called a bee lawn.
Bee lawns have a mixture of low-growing flowering plants as well as turf grasses. Properly planted and maintained, they can have a pleasing aesthetic appearance that shows neatness and care while achieving the environmental purpose of establishing a habitat for honeybees and native bees.
The University of Minnesota is playing a leading role in developing appropriate ways for homeowners to help pollinators by growing bee-friendly flowers from seed — not transplants — in their lawns. Mary Meyer, a professor and extension horticulturist at the university’s Landscape Arboretum, and James Wolfin, a University of Minnesota graduate student in the departments of entomology and horticulture who is researching bee pollinator habitat enhancement, have suggestions for creating a bee lawn that can make everyone happy — homeowners, neighbors and the bees.
How to create a bee lawn
"With a bee lawn, we try to introduce low-growing flowers that will bloom after being mowed and are good sources of forage for pollinators," said Wolfin. Good forage, he added, "Means that the nectar is high in sugar content and the pollen is high in protein."
He offered a five-step process to achieve those goals developed by the university’s bee and turf grass science lab through research.
1. Identify your turf. Your grass type will impact the ability of flowers to grow and bloom in the turf grass area. What really matters is the thickness of the leaf blade. This will determine how many nutrients the grass needs to survive and its rate of growth, which will affect its ability to shade out the flowers you're trying to grow.The University of Minnesota research found that Kentucky bluegrass and fine fescue species work well because they have thinner leaf blades and a slower growth rate than other grasses. Wolfin emphasized that because we normally try to keep flowers out of lawns and now are purposefully putting them into the lawn, we must reverse the way we think about grasses. The idea with a bee lawn is to promote flowers in the lawn rather than exclude them. If you're unsure of what type of grass or grasses you have in your lawn, you could take a sample to a local garden center or contact your extension agent and ask if they could recommend a source who could help you. You could also use a diagnostic tool developed by the Purdue University Turfgrass Science Department of Agronomy that helps users learn the essential features of grasses and identify major grass species that may be present in their lawns.
2. Choose your flowers. This will vary from region to region and from lawn to lawn within regions depending on how much sun or shade you have and how much foot traffic you get on your lawn. But, Wolfin said, there are three critical considerations in flower choices: They should be able to easily adapt to the soil type that exists in your lawn, they should survive mowing and they should be a good source for pollinators.
3. Modify your lawn management. Let your bee lawn grow higher than you would let a typical lawn grow, and mow it at a higher level than you have mowed previously. (In fact, fellow MNN writer Russell McLendon wrote a great overview of how to handle the tricky dance of mowing for bees in Why 'lazy' lawn mowers are heroes for bees.) But, Wolfin advised, still use the one-third rule — never mow more than one-third of the plant. Typically, homeowners set mower heights at 2.5 to 3 inches. With a bee lawn, Wolfin recommends letting grass and flowers reach a height of six inches and then mowing them back to four inches. You can still have a bee lawn at a lower height, but there may be fewer blooms, he said.
4. Disrupt the lawn before seeding. Before putting flower seed onto the grass, you'll need to do several things to maximize germination and, hence, the number of blooms. Two ways to do that are to scalp the existing grass and aerate the soil. Scalping is mowing the turf to an inch or less. If your mower doesn’t have a setting that low, set your mower on the lowest height possible. The reason to scalp the lawn is there must be seed-to-soil contact for the flower seed to germinate. The higher the grass, the greater the chance that flower seed will get caught up in the grass blades and not reach the soil. Aerating the soil will pull out soil cores and create holes throughout the turf grass area, thus increasing water flow through the soil, improving the chance for seed-to-soil contact for better germination and seedling growth as well as improving the overall health of the soil.
5. Sow seed at the optimal time. The best time to sow the seeds is in the late fall when the soil temperature is around 40 degrees F and grasses are going dormant.
What types of flower seed should you choose?
In the initial trials, University of Minnesota researchers found that Dutch white clover (Trifolium repens) was effective in attracting both honeybees and native bees. Last year they added lanceleaf self-heal (Prunella vulgaris ssp. lanceolata) to the trials and this year are adding creeping thyme (Thymus serpyllum), lanceleaf coreopsis (Coreopsis lanceolate) and calico aster (Symphyotrichum lateriflorum).
"The diversity we have found in these bee lawns is incredible," said Wolfin. "More than 40 species of bees native to Minnesota chose clover as a forage resource." There are an estimated 425 bee species in Minnesota, and the diversity numbers are based on a survey limited to urban parks. "That we had an estimated 10 percent of the bee species in the state on one flower species alone was really remarkable for us."
Increasing the number of flowering species in lawns will also increase the different species the bee lawn will attract. In the three years that researchers have been studying bee lawns, slightly more native bees have been observed than honeybees.
Homeowners in different regions of the country, of course, may want to use flower species in their lawns that are native to that region or that grow best in their area. There are several ways to determine which flowers to use in your bee lawn. Those include inquiring at local garden centers or asking your county extension agent. Another way is to visit the Xerces Pollination Resource Center.
One thing to be aware of is that since bee lawns are still a fairly new concept, Meyer and Wolfin are not aware of any bee lawn seed mixtures available in the general horticultural trade. Some local garden centers, such as several in the Twin Cities area, offer specialty mixes, but you'll need to ask. Seeds for the flowers you’ve identified for your bee lawn should be available as individual seed packets locally or via internet searches.
What about the neighbors?
For people who like to keep up with the Joneses, converting a standard lawn to a bee lawn will put you way ahead of them. In fact, you could be so far ahead that it would be a good idea to alert them in advance about what you're doing. Advance alerts will keep them from being surprised and possibly upset to see what they might think are weeds growing in your "once-perfect" lawn.
"Talk to your neighbors," said Meyer. "Help them understand there are flowers growing in your lawn for a reason, that they are for the bees. It’s a different mindset than a monoculture lawn, but I think most people will be OK with it because there’s a lot of positive publicity about bees now. I think people are more accepting today than they used to be."
It’s also a good idea to know about city ordinances and neighborhood covenants for lawns, she added. The limitations are generally on the height of the lawn. "If you get something over a foot, you could get into a zoning compliance issue I think if you do what James [Wolfin] said, grow to six inches and mow to four, you will be within a comfortable level for most people."
The future of bee lawns
Meyer and Wolfin credit the work of Dr. Marla Spivak and her team at the University of Minnesota’s Department of Entomology, which includes the Bee Lab, with raising awareness of both honeybees and native bees in the Twin Cities area.
Part of that work has involved exploring the social science aspect of bee lawns and how people perceive them. Hannah Ramer, a University of Minnesota graduate student, went through different areas of Minneapolis and asked people how they felt about their local government using taxpayer money to install bee lawns in local parks, said Wolfin. She found greater than 90 percent approval among parkgoers in Minneapolis. "It’s inspiring to see that the people we interacted with were extremely supportive of having bee lawns installed in their local area."
There are, after all, many advantages to promoting bee habitats in lawns. Bee lawns require less maintenance than a manicured lawn; they reduce fossil fuel use because they require less frequent mowing; they're conservation friendly because they require less water; they're low impact in regard to general maintenance; they provide pollination sources for urban gardening, which is on the rise in many communities. The lawn can also become a valuable resource for local beekeepers, or, if you're more focused in general on wild bee conservation, you'll see an incredible number of bee species using your lawn.
"I hope people are open to thinking about this," Meyer said. "Many people have never really thought about it. They’ve not recognized that an aesthetically beautiful landscape is not necessarily a healthy landscape ... that a typically beautiful monoculture lawn is not necessarily a healthy landscape. They’ve never really thought about what are the guidelines for taking care of a minimal maintenance lawn. They don’t know what to do in that regard. Education, I hope, can really help them."
And really help the bees.