The Mt. Cuba Center TOP PERFORMERS Program was created based on the research of Mt. Cuba Center in Hockessin, DE. Each of the plants in this program received a rating of 4.0 or higher in their trials (on a scale of 1-5, with 5 being the highest).
The Mt. Cuba Center research team uses the Trial Garden to evaluate native plants and related cultivars for horticultural and ecological value, and to highlight the ecosystem services native plants provide. Our partnership with Mt. Cuba will help to ensure that some of these great garden plants continue to be sold in the trade.
The Mt. Cuba Center TOP PERFORMERS Program consists of the following plants:
The HABITAT Program was created based on the research of Dr. Doug Tallamy. Each of the plants in this program provide food for caterpillars (larvae) of butterflies/moths of the Eastern United States.
An example is the caterpillar pictured to the right. This is the Monarch Butterfly caterpillar, a common and photogenic creature. The Monarch caterpillar only feeds on milkweed plants, such as Asclepias incarnata (Swamp Milkweed), A. syriaca (Common Milkweed), A. tuberosa (Butterfly Weed), and A. verticillata (Whorled Milkweed). Without milkweed the Monarch butterfly will not lay eggs and reproduce.
If milkweed isn’t your plant of choice, how about hibiscus? Hibiscus is a the host plant for the Spiny Oak-Slug Moth and the Delightful Bird-Dropping Moth (you know you want to see that one).
The HABITAT Program consists of the following plants:
The POLLINATION Program was created based on the research of Sam Droege (USGS) and Jarrod Fowler. Each of the plants in this program provide food for pollen specialist bee species of the Eastern United States.
An example is the bee pictured to the right. This is Colletes aesthivalis, a specialist bee of Heuchera americana (Coral Bells). This bee was not documented in Pennsylvania for over 100 years, until one of our employees noticed it in her garden in the spring of 2020. Without the Heuchera americana plant and flowers, this bee could disappear forever.
Many of these native specialist bees go un-noticed in our gardens, however others simply do no have the host plants they require for survival. Adding these plants to your gardens and landscapes is a great way to increase biodiversity and provide a valuable food source for our native bees.
The Pollination Program consists of the following plants:
Depending on the audience, people love them or hate them. To some a ”bee“ is the pesky yellow jacket lingering on your soda can. To others, a “bee” is the honey bee, a European species known for iconic hives and honey production. Children often associate bees with painful stingers, while some adults worry about potentially deadly allergies.
To me, a “bee” is all of these things and none of them. I keep hives for honeybees, I get angered by the yellow buzzing things like yellow jackets (which in fact are not a true bee), and I thoroughly enjoy watching various native bumblebees as they visit the diverse flora in my backyard.
Watching these various bumblebees, as they collect yellow/gold pollen on their legs is what alerted me to something unusual a few weeks ago. A garden visitor hanging out on my native Heuchera americana or Coral Bells. However, this visitor was a bit different.
Smaller than a honeybee and carrying bright orange pollen on her back legs, the bee keeper in me wondered – “Where is she finding orange pollen this time of year?” Typically red-orange pollen is an early spring occurrence on honeybees – a sign that the henbit is in bloom. (Henbit, or Lamium amplexicaule, is a European annual that has naturalized in the United States.) This observation lead me to investigate further.
If you are familiar with Heuchera americana, you know that the flower is nothing exceptional, predominantly green and tiny. For many years I would cut them off because they would flop. However this year, they were standing tall, in a site with more sun exposure than normal due to a recent tree removal. I quickly ripped open one of the small green flowers to discover a surprise – orange pollen.
My professional response to this was nothing other than “SQUEEEEEEE!!” What else can one say when you find a bee in your backyard that has not been documented in your state for 102 years?
Takeaway? Straight species native plants are important. Not only are there specialist bees for Heuchera, but there are specialist bees for Zizia, Asters, Goldenrods, Sunflowers, Coreopsis, Eupatorium, and so much more! Jarrod Fowler has compiled a great resource list of specialist bees and native hosts. What I have learned from this experience is that there are MANY unknowns when it comes to specialist bees. Will they collect pollen from cultivars of the straight species? This is something the scientists don’t have an answer for. Continued monitoring is needed and citizen scientists can play an important role in this monitoring.
Bumble bees are perhaps one of the most widely recognized bees that grace our gardens and landscapes. With their characteristic buzzing and noticeably furry bodies adorned with pollen, bumble bees bring both joy for us as observers and ample pollination benefits to a large array of landscape plants and food crops. Bumble bees are in fact a genus of about 50 individual species that share similar attributes, 28 of which live in the Eastern US.
Unlike European honey bees, bumble bees form annual colonies, meaning that each year a new queen emerges from hibernation to build and populate an entire colony. Over the course of the spring and summer the queen and the workers she herself incubated, oversee the rearing of several more generations of female workers. These workers collect the pollen and nectar necessary to support the growing colony. In the late summer, male drones are born that mate with a select few females. These young females, called gynes, forage for a couple weeks to build enough energy stores to hibernate through the winter. No other member of the colony lives through the winter frost. In the early spring, these young queens emerge and each begin her own nest. And the cycle continues…
With their large size and long tongues, bumble bees are able to access pollen and nectar from a large variety of flower types; they are called generalists in that sense. That is a good thing because members of the colony need to feed from February until late fall, so it is critical that they have a wide variety of food sources available. Bumble bees can do what few other bees can… Buzz! What we hear as buzzing is called sonication and has a critical role in pollen collection for the bees. Buzz pollination occurs when the bees rapidly vibrate their flight muscles while holding onto the flower anthers (male flower parts that hold pollen). This vibration releases pollen that would otherwise be inaccessible. The bees can then brush the pollen from their bodies and head and pack it into the pollen baskets on their rear legs. Food crops like tomatoes, blueberries, and apples rely on buzz pollination, so thank a bumble bee next time you slice that tomato for your sandwich!
What Can You Do?
So, how can you ensure a healthy population of bumble bees in your garden or community?
Plant flowers, trees, and shrubs with a variety of bloom times, ensuring that the bees will have nectar and pollen sources from early spring through late fall.
Resist raking and clearing in early spring so the young queens can emerge safely from the ground and begin their broods.
Leave piles of plant debris and abandoned rodent holes be. These are the favorite nesting sites of bumble bees as they are already built, protected, and ready for a new queen to begin her brood.
Resources & Further Reading:
Holm, Heather. Bees: An Identification and Native Plant Forage Guide. Pollination Press, 2017.
Holm, Heather. Pollinators of Native Plants: Attract, Observe and Identify Pollinators and Beneficial Insects with Native Plants. Pollination Press LLC, 2014.
Mader, Eric, et al. Attracting Native Pollinators: Protecting North Americas Bees and Butterflies: the Xerces Society Guide. Storey Pub., 2011.
We all want to attract pollinators, but many times we don’t have the space to include every plant an insect might find valuable. What is the best way to break down the massive lists of pollinator plants? Let’s look to the research.
From 2012-2015, Master Gardeners from Penn State Extension studied 86 native plant species and cultivars for their attractiveness to pollinators. The winner? Hands down, it was Pycnanthemum muticum or Clustered Mountain Mint. Oh no, a mint you say? Although it looks like a mint and smells sort of like a mint, it doesn’t always behave like a mint spreading everywhere (although I can’t lie, in some soils it does).
If you have space to grow it, Clustered Mountain Mint will attract the largest number of different pollinator species to it’s tiny white flowers. Bees, flies, wasps and more are frequent visitors. The great part is that these insects are so intent on feeding, that they could really care less about you observing their feast. The plant will be alive with activity, almost humming, which is a delightful observance. (Learn more about Clustered Mountain Mint here https://cavanos.shop/product/pycnanthemum-muticum-clustered-mountain-mint/)
Another great plant that did very well in the trial was Eupatorium dubium (Eutrochium dubium) or Coastal Plain Joe Pye Weed. This Joe Pye has a shorter stature than many, topping out between 3-4’ for me. It is also more tolerant of dry soils which is great for folks with drier soil who REALLY want to be able to grow a Joe Pye!
Coreopis ‘Zagreb’ while a cultivar, placed in the top 20. While this Coreopsis might seem common place to some, the fact that it blooms earlier in the season is great for the pollinators in early summer. Aster ‘October Skies’ (Symphyotrichum) is another great flower in the top 20, with a lovely blue flower in the fall.
While any of the top 20 plants would be great additions to your garden, don’t feel like you should limit yourself to only these 20 plants. Biodiversity in nature is important, and if your entire neighborhood plants the same 20 plants, you could miss out on some really cool insects! Like a specialist bee that only visits Helianthus (Sunflower), or only visits a certain Heuchera (Coral Bell). Let’s get planting!
June is National Pollinator Month. At Cavano’s Perennials we value the role that our pollinators and beneficial insects fill – bee, bird, butterfly or bat – we love them all. We continue to develop habitat gardens on our property so that we can enjoy not only the physical beauty of having the insects onsite, but also to utilize many benefits they have to offer.
Pollination (the obvious). Our display gardens incorporate food – greens, potatoes, tomatoes, squash, etc – food that is then harvested and given to our employees. Without pollinators, much of that food would never come to fruition.
Insect control. Some beneficial insects eat other insects, many of which can be problematic in a nursery. Parasitic wasps are a natural enemy of pest insects, and a large population can be very beneficial.
Food for other creatures. While this may be a sad reality to some, our pollinators are the beginning of the food web. They provide a vital source of nutrients for birds and small mammals. Without the caterpillars of butterfly and moth species, many of our songbirds would disappear. This food source is vital to the diet of a baby bird.
As we begin National Pollinator Month, stay tuned for more information about creating pollinator habitat, specific plants of interest, management of pollinator areas, and much more. #PlantsDoThat #CavanosGrows #PlantsMakePeopleHappy #Pollinators