How to Grow a Pollinator Garden in Raised Beds
Pollinator gardening is a popular way for plant lovers to support those all-important garden workers. We just love a functional and beautiful raised bed garden. In this article, beekeeper Melissa Strauss will help you build a raised bed garden that the butterflies will be talking about for miles.
Contents
As someone passionate about pollinators, I am always looking for new and functional ways to add more pollinator plants to my garden. Recently, I’ve been turning a number of my raised beds into pollinator-friendly flower beds. With so many pollinator populations faltering, I want to provide as much food for those little guys as possible. I also enjoy seeing them visit.
If you’re already all set up in the garden with raised beds, it’s easy to convert those beds to pollinator gardens. If you’re just getting started, it is a bit more work, but we are here to help point you in the right direction and help you include the right elements to have a bustling pollinator garden. Let’s get started!
Know Your Local Pollinators
An important factor in creating a pollinator paradise is to know which pollinators you are supporting. Some pollinators will come as no surprise, while others may not be as well known. Knowing which pollinators are important in your region will help you determine which plants are integral to building a comprehensive pollinator garden.
Bees
We are all familiar with the famous honey bee, or Apis mellifera. Of more than 20 recognized sub-species of this type of bee, not a single one is native to the United States. However, they are important, agriculturally speaking, so don’t hesitate to consider them when selecting plants.
Without going into too much detail about the taxonomy of bees, there are more than 4,000 different bee species native to the United States. These range from the tiny Perdita minima to the very large Xylocopa, commonly known as the carpenter bee. Every single one of them pollinates flowers.
All bees have ultraviolet vision. They see and gravitate toward flowers that are blue, violet, white, and yellow. They cannot see red, and it appears black to them, which signifies danger. Honeybees seek out large groupings of flowers and are not particular about native status. However, many native bees depend on the pollen and nectar from various native plants to support their young.
Butterflies
Butterflies are more particular about the plants they prefer. Each region has specific butterflies native to that area. More than half of butterfly species in the US are considered to be declining. One-third of the total species are in danger of extinction.
Preserving the habitats of native butterflies is a very important aspect of pollinator gardening. Butterflies are most attracted to flowers that are short and tubular or grow in flat-topped umbel-like clusters. They are especially attracted to red, pink, purple, yellow, and orange flowers. Each butterfly also has at least one host plant, but more on that in a minute.
Hummingbirds
Hummingbirds are great little pollinators, and is there anything cuter? It would be impossible for me to choose a favorite pollinator. But I do very much enjoy watching hummingbirds flit about the garden. Seeing these little birds gives me a sense of accomplishment in creating a diverse environment for pollinators.
These pocket-sized birds are native to the Americas. Of just under 400 species, all of them are efficient pollinators. Their uniquely adapted beaks make them vital for pollinating certain flowers that other pollinators can’t access. Presently, 21 species of hummingbirds are on the endangered or critically endangered list due to habitat loss.
Hummingbirds are attracted to tubular-shaped flowers. Red is the color that appeals to them most, but they are also attracted to pink, yellow, and orange. Flower structure and nectar content are more important than color to these pollinators, though.
Bats
Bats may not be the first animal to come to mind when you think about pollination. Their association with other more nefarious creatures of the night can make their presence a bit creepy. In reality, these nocturnal mammals are very important in the pollination world.
Bats are responsible for pollinating more than 500 species of plants worldwide. Some of the more common plants pollinated by bats include agave, banana, guava, and many night bloomers. They are also vital to controlling the population of less desirable insects, like mosquitos. Keeping these guys close at hand has lots of benefits.
Unfortunately, their populations are declining rapidly. According to the US Fish & Wildlife Service, more than 50% of North American bat species are in decline. Adding plants that are attractive to bats and offering them a place to roost is a good way to help support these pollinators.
Moths
Just like their cousins, the butterflies, moths are vital pollinators. Moths come out at night with bats and do a lot of great pollinating. They are especially drawn to nightshades such as tomatoes and eggplants, to name a few.
While moth populations seem to be less affected by the issues plaguing other pollinators, their numbers are still declining. There are ways that you can support moths in your pollinator garden, as well.
Other Insects
Bees and butterflies aren’t the only insects that pollinate. If you want that magnolia tree to bloom, attract beetles to the garden. Wasps are best known for pollinating orchids, but they play a role in pollinating fruit trees and garden flowers, too.
They are also helpful in controlling populations of nuisance insects like aphids and grasshoppers. They not only pollinate, they minimize the need for pesticides, which is very helpful for other pollinators. You can help support these insects with your pollinator garden, as well.
Choose a Location
This is a department where raised beds do a lot to simplify the creation of your garden. When you are planting a conventional garden, there are a lot of factors that go into preparing the area. From soil to sunlight, there are often time-consuming, physically taxing, and costly amendments to make.
Using raised beds makes selecting a space much easier. They also make it possible to garden in less conventional spaces. In an urban setting, a raised bed garden can create a pollinator refuge. If your outdoor space is a concrete patio, raised beds are a great solution. A raised bed garden is very accessible. There is no need to do a comprehensive soil test or make soil amendments. If you have poor or easily compacted soil, raised beds save a lot of work.
Many plants that attract pollinators grow best in full sun conditions. If you live in a very warm climate, full sun has a different meaning than in other places. Ideally, your garden should get about six to eight hours of sun daily, preferably early in the day.
The afternoon sun can be harsh and dehydrating. Using raised beds gives you to option of planting in high-quality soil while also choosing the position of the garden. Pollinators like to keep warm, which is another reason to place your beds in full sun.
Select Your Beds
There are several types of raised beds to choose from, and there are advantages and drawbacks to consider. When selecting your beds, you should consider both their form and function. Longevity is another factor to consider. How long do you want your beds to last? Quality beds save money in the long run because they simply hold up better. Material is another important factor.
Inexpensive wooden beds will serve your purpose for a time, but don’t expect to get more than one or two years out of them. The wood used in these beds tends to be thin, and the connections can be less than ideal. If you suspect that you won’t be tending this garden for long, these are fine for starting out.
If you love the look of wooden beds, as I do, cedar beds are a great investment. They will cost a bit more than less expensive wooden beds, but in the long run, you’ll get more bang for your buck. For small-space gardening on a patio or deck, there are some wonderful elevated options. Cedar ages nicely and weathers well.
For the ultimate in durability and longevity, you can’t beat metal raised beds. Over the years I’ve started replacing my wooden beds with metal ones, and they really do stand the test of time. They come in lots of shapes and sizes, and some include a solid base that makes them perfect for patios.
If you are really ambitious, you can construct your beds from other sturdy materials. Stone or brick beds are stunning and functional. They are also costly, backbreaking work to construct, and very permanent. For those gardeners willing to take on that type of commitment, it does make a gorgeous raised bed garden.
Design Your Space
Depending on the size and orientation of your space, design, and planning will carry different weights. There are lots of great design ideas to consider for any space. In smaller spaces, think vertical. By adding a trellis to your raised bed, you can grow flowering vines. Many flowering vines are very attractive to hummingbirds and other pollinators.
If you are placing your beds on a patio or deck, consider the overall layout of the space. Place your beds in spaces that don’t interrupt the flow of traffic. Plan these spaces so that you have easy access to all of your plants. Again, vertical elements can add a lot of personality to a space. The more flowers you can pack into the space, the more pollinators will visit.
If you have a lot of space, the sky is the limit. Your raised bed garden can be as intricate as you desire. Consider the flow of traffic when placing your beds. Set them up in a way that all of your plants will be accessible.
Fill Your Beds
A great element of raised bed gardening is being able to start right off with high-quality, nutrient-rich soil. Filling your beds with a quality soil mix can get very expensive. If your beds are shallow, you may want to simply fill them with a raised bed mix.
I find taller beds are easier on my back, and they also accommodate deeper root systems. Healthy roots make healthy plants. Smaller plants in the garden develop roots about 12″-18″ deep. Taller beds can eat up a ton of soil. If you have deeper beds there are things you can do to minimize the expense of filling them properly.
You can fill the lower portion of your taller raised beds with other organic matter like leaves, compost, branches, and grass clippings.
Fill the top 12″-18″ of your beds with a good quality soil mix. Over time, the organic matter on the bottom will break down and enrich the soil. In this way, you not only save money, but you repurpose yard waste and clean up in the process.
Select the Right Plants for Your Space
Now for the fun part. After you set up your beds, it’s time to select the plants to fill your pollinator garden. When selecting plants, you should consider your climate and the amount of time you will have to tend to them. Some plants are more high maintenance than others. Group together plants that have similar watering and fertilizing needs.
Native Nectar Sources
Planting native tends to be a hot-button topic in a lot of gardening circles. Some gardeners feel very strongly about maintaining a native landscape, while others are not as concerned. Whether you fall into one of these groups or somewhere in between, native plants are an important aspect of a healthy pollinator garden.
Honeybees, as I mentioned, are not native to the United States. These insects originated in Asia and Europe. They tend to be opportunistic when it comes to collecting pollen and nectar. These bees don’t rely on specifically native plants to thrive.
Native bees and butterflies, however, do rely on native plants. You may still see these insects visiting non-native plants, but it’s more out of necessity than preference. The plants that naturally bloom at various times of year are important to native pollinators. Not all nectar is equal, and native pollinators are adapted to certain types of nectar during each season.
Some pollinators rely almost exclusively on a specific plant for reproductive reasons. I will address this in a moment. Suffice it to say that planting native flowering plants in your pollinator garden is important. Native plants also tend to be lower maintenance, as they are well adapted to the conditions of your region.
Many pollinators rely on both nectar and pollen to sustain their populations. While adult pollinators feed mainly on nectar, they often bring pollen home. They feed their larvae with pollen as it is a great source of protein and other nutrients.
All plants produce pollen, but not all plants produce nectar. Be sure to stock your pollinator garden with plenty of nectar plants. Some of these include:
- Salvia
- Goldenrod
- Anise hyssop
- Indian Blanket Flower
- Bidens
- Verbena
- Coreopsis
- Liatris
- Joe Pye Weed
- Black-eyed Susan
Butterfly Host Plants
Adult butterflies have their favorite nectar sources, but they won’t turn down other nectar sources when they are hungry. However, their larvae are a different story. All species of butterflies and moths have specific larval host plants. These are the plants that they lay their eggs on and which provide the first food for their young.
Without host plants, you’ll probably still see the occasional butterfly. If you want to see a lot of action, though, host plants are imperative. Butterflies will return to places where they have identified host plants. If you’re lucky, you might just get to watch the entire lifecycle play out in your garden. Some host plants are too large for a raised bed garden, but many are just right.
This is by no means an exhaustive list, but here are a few host plants that you can add to your garden to attract more butterflies.
- Monarch – All types of milkweed (look for types that are native to your region. These will provide the ideal food for their larvae based on migration patterns.)
- Painted Lady – Thistle, hollyhock, aster
- Fritillary – Violets, passionflower
- Zebra Longwing – Passionflower
- Black Swallowtail – Dill, fennel, parsley
- Grey Hairstreak – White clover, okra, downy milk pea
- Cloudless Sulphur – Senna, pea family
- Silvery Checkerspot – Purple coneflower
- Karner Blue – Lupine
Annual Food Sources
Most of the native plants in your garden will either be perennials or self-seeding. These plants are great for seasonal nectar, but they tend to have shorter blooming seasons than many flowering annuals. If you want to keep pollinators fed all year, planting flowering annuals is a great way to bridge gaps in native blooming cycles.
Most pollinators will stake out spots where there are a lot of flowers in close proximity. For bees, collecting nectar to bring back to the hive is exhausting work. It requires a lot of energy. Nectar is energy. The more they can collect using as little energy as possible, the more the better. The situation is much the same for butterflies and hummingbirds. They will seek out gardens with the greatest amount of nectar to collect.
Seasonality is important when selecting these plants. During times of the year designated as a ‘nectar flow,’ there will be an abundance of native flowers in bloom. Pollinators keep very busy during these periods. During the in-between times, you can bridge the food gap with flowering annuals. If it has flowers and isn’t considered invasive, it’s a good nectar source.
Some great flowering annuals to plant in your pollinator garden include:
- Zinnias
- Cosmos
- Sunflowers
- Marigolds
- Pentas
- Nasturtiums
- Pineapple sage
- Sweet almond bush
- Porterweed
Add a Water Source
Another important element to add to your raised bed pollinator garden is a water source. Like the rest of us, pollinators need water for drinking and cooling themselves. They are far more likely to return to your garden if there is a source of water nearby.
If you live near a stream or a pond, you are at an advantage. If not, there are lots of ways to create a water source for your garden. I prefer to use birdbaths in my garden. It’s easy to refill them with a hose, and they don’t require assembling and taking apart in order to do so.
Other options include a small fountain, a dripping bottle, or a watering dish. Place some small stones in the bottom of your receptacle for smaller insects to perch on, or you may end up with a lot of drowned bees.
There is the question of freshness to consider in terms of the water you put in your water source. Bees, in particular, locate water by smell. Fresh rainwater is unlikely to attract them. They will be more attracted to water that is chlorinated or contains decaying organic matter. This raises the issue of mosquitoes.
Mosquitoes lay their eggs in standing water. If you let water sit out in the garden without refreshing it regularly, you’ll draw mosquitoes. This creates quite a conundrum. BTI dunks are an ideal solution to the problem. These will kill mosquito larvae but are harmless to pollinators.
What to Avoid
The main things to avoid using in your pollinator garden are chemical pesticides and weed killers. Chemical pesticides are an obvious no-no. If it kills ants and aphids, it will probably kill bees and butterflies. Attracting beneficial insects like ladybugs, lacewings, and wasps will help to keep nuisance insect populations down. Native plants are a great draw for them.
You should also avoid using weed killers in and around the pollinator garden. Even though you have provided pollinators with a veritable buffet of nectar and pollen, there are other native plants that help out.
Most of the plants we call weeds are just native plants that don’t have a ton of ornamental appeal. If they flower, they’re pollinator food. Leaving these plants to grow in areas where they don’t bother your aesthetic sense is another way to attract and keep pollinators in the garden.
Final Thoughts
Building a raised bed pollinator garden is a great way to help sustain pollinator populations. Pollinators are responsible for pollinating more than a third of the foods we eat. Sadly, in spite of efforts to support them, more and more of these vital insects and animals are showing up on endangered species lists. Pollinator gardens are a great way for everyday gardeners to play a role in preserving vital pollinator populations.