native plants

How to stop bunnies from eating your pollinator garden

Don’t be fooled by extreme cuteness: bunnies are every pollinator gardener’s nightmare. You spend precious time and money planting a native garden to feed pollinators, only to end up feeding bunnies instead. In the TPI gardens at Tufts, we face our fair share of bunny herbivory. But, we’ve also learned a few strategies for combating hungry rabbits, including a list of which plants rabbits avoid entirely. Read on to learn our tips for how to bunny-proof your pollinator garden, and visit our native plant sale in mid-June to pick up plants that will thwart the rabbits!

With a little preparation, your pollinator garden can feed more bees than bunnies PC: jjjj56cp, Flickr

1. Prioritize rabbit-proof plants

The single best way to avoid having your garden munched on by rabbits is to grow plants that rabbits do not like to eat. Over the past three years, we have kept track of the fates of over 30 different species of native plants in our gardens. Although many of them, in one year or another, have been munched on by rabbits, some species have been avoided entirely. Here is the list of plants from our garden that have never been eaten by rabbits:

When other plants become a light snack for rabbits, New York ironweed does not. Its stems are tough and fibrous (some might even say iron-like), and their leaves contain bitter chemicals.

Mountain mint (Pycnanthemum spp., e.g. P. virginianum, P. tenuifolium)
Anise hyssop (Agastache foeniculum)
Bee balm (Monarda spp., e.g. M. bergamot, M. punctata)
New York ironweed (Vernonia noveboracensis)
Foxglove beardtongue (Penstemon digitalis)
Golden Alexander’s (Zizia aurea)
Goldenrods (Solidago spp. e.g. S. sempervirens)
Wild senna (Senna hebecarpa)
Joe-pye weed (Eutrochium maculatum)
Boneset (Eupatorium perfoliatum)
Cutleaf coneflower (Rudbeckia laciniata)
Sneezeweed (Helenium autumnale)
Partridge pea (Chamaecrista fasciculata)
(most herbs*)

2. Avoid tasty plants

In a similar vein, a great way to make your garden bunny-proof is to not grow the plants that rabbits love. Here’s a list of plants from our gardens that fed more rabbits than pollinators, and which should be planted with caution:

Symphyotrichum spp.asters (S. novae-angliae, S. laeve, S. prenanthoides)
Blazing star (Liatris spicata, L. scariosa)
Wild false indigo (Baptisia spp.)
Cardinal flower (Lobelia cardinalis)
Swamp milkweed (Asclepias incarnata)
Purple coneflower (Echinacea purpurea)
Cup-plant (Silphium perfoliatum)
Black-eyed susan (Rudbeckia hirta)
Sunflowers (Helianthus spp.)
red columbine (Aquilegia canadense)
Culver’s root (Veronicastrum virginicum) — not always eaten

3. Create an unappetizing display by mixing plants

We’ve found that tasty plants are often avoided when planted among distasteful plants, so try to mix and match. This means your tasty asters stand more of a chance if mixed in with lots of distasteful mountain mints, ironweed, and goldenrods. Pollinators appreciate the diversity too—the more diverse your garden, the more kinds of pollinators you will attract! And, from an aesthetic perspective, inter-mixing plants means that any rabbit herbivory that does occur will be far less noticeable.

4. Protect vulnerable plants

Rabbits love eating the youngest plants. Often, young leaves have not yet accumulated as many distasteful chemical compounds as older leaves. In our gardens, for example, young emergent sunflowers (Helianthus annuus) and cup-plant (Silphium perfoliatum) are frequently nibbled as seedlings, but are left untouched when they are larger. By protecting young plants with fencing, your garden will have the blooms you want later in the season!

The same applies to woody plants and saplings, but for a different reason. Young wood is soft, sweet, and easily chewed by rabbits and rodents. Be sure to fence young saplings in their first years–especially over winter–to prevent girdling and other herbivory that can kill your long-term investment.

5. Use your local knowledge

Keep in mind that our lists of plants (both enjoyed and rejected) reflect the tastes and preferences of rabbits in urban Massachusetts, as well as the context of our campus garden. So, to make your garden as bunny-proof as possible, learn from experience. If bunnies in your neighborhood never touch the wood asters and swamp milkweed in your garden, then by all means, plant, plant, plant. Conversely, if the bunnies in your neighborhood have a penchant for anise hyssop, then definitely don’t keep planting while expecting a different result.

Do you have tips for thwarting bunnies in your pollinator gardens? Drop us a comment!

*Although we advocate for growing native, you can add fragrant, non-native herbs like lavender, rosemary, thyme, borage, and oregano to make your garden even more bunny-proof. The nasty compounds in most mint-family plants are quite distasteful to bunnies.

educate

The 5 best ways to make your yard pollinator friendly

by Atticus Murphy

Planting a pollinator garden is all the rage these days, but if you’ve never gardened before, it may seem like a daunting task. Don’t worry, it doesn’t have to be complicated! You can support pollinators in your yard by taking several easy and important actions. Tufts Pollinator Initiative has distilled it down to the 5 most important actions you can take today!

1. Plant a diverse set of flowering plants

Diversifying the flowers in your garden is the best way to support the most types of pollinators. Shoot for diversity on all levels: color, flower shape, size, and, most importantly, bloom time. Each pollinator species might only be active for a few weeks and visit a small number of plants, so adding flower diversity throughout the year will almost always boost your yard’s pollinator diversity (and give you blooms year round!). A good place to start? TPI’s top 10 flowers for bees!

Diversity begets diversity: we’ve planted over 15 flowering species at our campus gardens and seen over 115 species of insect pollinators!

2. Add woody plants like trees and shrubs

Native trees and shrubs make excellent additions to pollinator gardens because they provide resources that herbaceous, perennial flowers often don’t. For instance: many native trees and shrubs bloom early in spring, at a time when few other plants are blooming on the landscape. In addition, trees and shrubs provide homes for solitary bees and many butterflies depend on tree leaves to complete their life cycles. As a bonus, trees and shrubs require very little maintenance after their first few years and provide shade for decades! To help you pick, check out TPI’s top 10 trees and shrubs for bees.

Unequal cellophane bees (*Colletes inaequalis*) depend on pollen and nectar from early-blooming red maple trees to complete their life cycles.

3. Grow native plants

To support our native pollinators, grow native plants. Our native pollinators have been in relationships with native plants for thousands of years, and sometimes have evolved such a picky diet that only one or a few native plant hosts will do. Avoid non-native ornamental plants (esp. doubled cultivars) like petunias and impatiens–they either offer unsuitable food resources, or have been bred to offer no pollen and nectar whatsoever. Compared to traditional ornamental plants, native plants can survive is less than ideal soils and periods of droughts, while still filling your garden with bursts of color. Pick up your locally-grown native plants at TPI’s summer plant sale!

fall bees fueling up on new england aster before winter — Native bees love native flowers like New England aster.

4. Minimize herbicide and insecticide use

It’s simple: to keep insect pollinators around, don’t apply pesticides. Herbicides kill the flowers that pollinators use for food. Leaving weedy flowers (“weeds”) to bloom creates abundant and diverse resources for pollinators. And insecticides like neonicotinoids are deadly for pollinators: remember, anything that kills a mosquito almost certainly kills a bee. Even if you apply these chemicals to a separate area of your yard, they have a high potential of running off into the surrounding pollinator friendly areas. Stick to hand weeding problem plants whenever possible and try handling pesky insects in chemical-free ways like limiting standing water or having nests removed.

5. Mow remaining lawn infrequently

Conventional turf lawns are fun play spaces, but monocultures of grass do not support pollinators, so it’s always best to limit the amount of lawn on your property. For any lawn that you keep around, one of the most impactful things you can do is to mow as little as possible. Even going from mowing weekly to mowing every other week leads to dramatic increases in the number of pollinators and flowers found in lawns. You don’t need to let the lawn look truly wild to achieve big benefits either! Leaving a margin of unmowed grass around the edge can provide valuable nesting habitat for bees and low-growing flowers like white clover.

By mowing your lawn less frequently, you can support native pollinators like bicolored striped sweat bees *Agapostemon virescens*!

Following these simple steps can help you take big strides towards making your patch of the urban landscape a haven for pollinators. One of the most rewarding things about implementing steps like these is that you are nearly guaranteed to see returns after just a small amount of investment–if you plant it, the bees, butterflies, wasps, and hover flies really will come. Happy gardening!

To learn more, check out our publication on pollinator gardening produced in collaboration with Tufts CREATE Climate Solutions.

cultivate

Pipevine Swallowtails and the case for caterpillar gardening

When you think of gardening for pollinators, you most likely think of beautiful flowering plants which attract bees, butterflies, and other insects by offering copious amounts of nectar or pollen. But flowers cannot give all pollinators the food they need. Butterflies in particular can be very picky when deciding what to eat when first starting out their lives as caterpillars. Most butterfly species have evolved to specialize feeding on one or a handful host plants. In a sense, when it comes to supporting butterfly communities, providing ample host plants for these soon-to-be-butterflies could be just as beneficial as planting nectar flowers for adults!

Pipevine swallowtail eggs are laid in small clusters so that when they emerge, these caterpillars work together eating leaves in small groups

The Pipevine swallowtail Battus philenor is one butterfly that benefits tremendously from the gardening of its favorite plant, Pipevine Aristolochia, after which it is named. Both Pipevine and the butterfly with which it shares its name is native across eastern North America, including Massachusetts. The plant itself is highly toxic and could cause severe kidney problems or even cancer if ingested by humans, but Pipevine swallowtail caterpillars could not care less.

These caterpillars have evolved not only to cope with the toxins in the plants, but to actively seek them out. Pipevine swallowtails, like many other butterflies, including Monarchs and their beloved milkweed, acquire the toxic chemicals present in their host plant and sequester them. As caterpillars they build of reserves of this chemical making them unpalatable to potential predators for the rest of their life. This is part of the reason many butterflies display such bright and captivating scales – it can be a signal to predators that nothing good will come from eating them.

In the right conditions Pipevine can scale great heights clinging to trees or other supports

Though these caterpillars cannot get enough of Pipevine, the adult swallowtails themselves do not nectar on the flowers it produces. Pipevine, like the name suggests, produces curved flowers that resemble a smoking pipe which is not conducive for a butterfly proboscis. Dutchman’s pipe Aristolochia macrophylla, is the most common species in eastern North America, and produces small tubular flowers with a small circular entryway. Into that entryway go flies which are actually attracted to the flower’s fragrance. Upon entering the narrow pipe, the flies get a little stuck, catching some of the flower’s pollen and carrying it with them until they end up in another flower which they help fertilize. After fertilization, the plant produces great seed pods which, when rooted and grown, will provide more food for those hungry caterpillars.

Before you start thinking this toxic, fly-attracting plant might not be the right fit for your garden, consider that Pipevine has been an immensely popular ornamental plant since Victorian times. It is an ideal option for trellises, fences or pergolas, providing plenty of shade when mature! If you are interested in attracting these beautiful butterflies to your home or garden in the future be sure to water your Pipevine as it needs lots of water and give it a place to climb. Be sure, too, to get Aristolochia macrophylla specifically, as some species will not support these caterpillars or might even be invasive – moreover macrophylla will provide the best shade (it is given the Greek name meaning ‘large leaf’) and will attract some marvelous butterflies looking for the right place to lay their eggs.