Summer Shrubs

When the weather heats up and you wonder what will be there to sustain native insects, it’s always nice to see the summer shrubs kick into gear. Take a walk through my garden and see what shrubs are blooming now and what insects are benefiting from them. Of course, the beauty for us is just icing on the cake.

White meadowsweet( Spiraea alba var. latifolia) has spires of tiny white flowers that attract small bees and lots of beetles like longhorn beetles. The seeds are pretty fertile, and I pot up a number of seedlings for friends and plant sales each year. Read my previous blog about our native spireas here.

St. John’s wort is absolutely a group of summer plants and there are several blooming now or just finished.  Golden St. John’s wort (Hypericum frondosum) is usually the earliest and it is finished now. The star is currently bushy St. John’s wort (Hypericum densiflorum) and a modest side of St. Andrew’s cross (Hypericum hypericoides). All are popular with bumble bees and other bees.

Summersweet (Clethra alnifolia) is aptly named and I’ve got two cultivars blooming now: the pink ‘Ruby Spice’ and the shorter ‘Hummingbird.’  The sweetly smelling racemes are visited by butterflies, bees, and wasps.

Clethra alnifolia

Clethra alnifolia 'Ruby Spice'

Bottlebrush buckeye (Aesculus parviflora) is a shrub that needs a lot of room and sun to bloom well, but I also grow it in part shade where the plant is smaller and the blooms are fewer. The Eastern tiger swallowtails love on this one for weeks, occasionally joined by silver-spotted skippers and large bees.

Tiger swallowtail on bottlebrush buckeye (Aesculus parviflora)

Two of our native azaleas bloom in the summer. Sweet or smooth azalea (Rhododendron arborescens) hasn’t yet found a sweet spot in my yard and is currently in a pot where it only has a few blooms this time of year, but it would be great for other people!  I have too much deer presence to give every azalea a home. Plumleaf azalea (Rhododendron prunifolium) has found a perfect home next to my front porch where it happily sports red flowers on my birthday every year in July and attracts large butterflies and hummingbirds.

Rhododendron arborescens

Rhododendron prunifolium

Aralia spinosa flower cluster full of
different bees and butterflies

Last but not least is a giant of a plant, and not everybody’s favorite at all, the devil’s walking stick (Aralia spinosa). This large shrub is covered with prickles, from the bark to the very large, compound leaves (the prickles are on the underside of the leaves/leaflets). It also has a tendency to sprout from the roots, especially if the root zone is disturbed by digging or if the plant suffers damage (which is what happened in 2014 and I wrote about it). I find these suckers easy to pull out (and not hard to pot up for friends and plant sales). This species creates a huge inflorescence in summer; the hundreds of tiny flowers in it are very popular with butterflies large and small as well as a number of bees. I love to get binoculars and watch to see what visits way up there. It is blooming now!

My previous post on late spring and early summer shrubs can be found here. I hope some of these ideas will inspire you to plant some summer shrubs in your garden.

Lula Lake and Falls

We recently drove up to visit Lula Falls which is described as one of the showiest waterfalls in Georgia. The property containing the lake and falls is managed by the Lula Lake Land Trust and it is located south of Lookout Mountain in Walker County, GA, not far from Chattanooga, TN. It is open to the public 40 days a year, on designated weekends May through November (check their website to be sure).

Background from their website: "As early as 1958, Robert M. Davenport began to acquire pieces of property that would later form the core of the land trust project. These original acquisitions included two exquisite natural features, Lula Lake and Lula Falls. The Lula Lake Land Trust, established by the will of Robert M. Davenport in January of 1994, seeks to protect and preserve the natural beauty and abundant resources within the Rock Creek watershed for the benefit of present and future generations by fostering education, research, and conservation stewardship of the land. By the time of his untimely death in 1994, Robert M. Davenport had acquired over 1,200 acres surrounding Lula Lake. Since then, the Land Trust has increased protection within the watershed to over 8,000 acres.

Mr. Davenport had talked to his family about long-term goals for Lula Lake such as preserving the property and conducting biological inventories to identify any rare or unique plants and animals. One such species, Virginia spirea (Spiraea virginiana), was found on the property and previously known from only one other location in Georgia. When learning this, Mr. Davenport became completely convinced of the importance of preserving this unique area for future generations."

Sweet azalea (Rhododendron arborescens)

If you’ve visited Lula Lake before, you might be surprised to find a new parking area as well as a mandatory fee ($10 per car, just implemented in June). The volunteers gave us a map of the trails and we headed off to find Lula Falls. The well-maintained trail was flat and easy walking through a variety of conditions, from cool hemlock forests to sunny openings. We followed along beside Rock Creek the entire way. I wasn’t sure what to expect in terms of plants, but our first stop near the nature trail area had a welcome surprise. Next to the creek was a blooming smooth azalea (Rhododendron arborescens). Honestly, that was worth the drive alone!

Variety of Silphium asteriscus

Ginger (Hexastylis sp.)

We saw a lot of blooming rosinweed (Silphium). I assumed it was starry rosinweed (Silphium asteriscus) but was surprised to see how hairy the stem was; I didn’t remember mine at home having such hairy stems. I snapped a few pics to share on a Facebook group when I returned. I learned more about potential varieties of this species as a result and was pleased with the interest the discussion sparked in the group about Silphium identification.

Witchhazel (Hamamelis virginiana)

Hemlock (Tsuga canadensis)

Since we stayed on the path, we saw very little of the overall plants, but I was very pleased with the diversity of what we were able to see. I didn’t keep a list (we were pressed for time to complete the hike by the 5 pm closing time), but I was constantly delighted with the number of tree and shrub species that we saw as well as the herbaceous layer.

Rock Creek from top of  the falls that drop into the Lake

You can’t hike along a place called Rock Creek and not expect to see rocks – they were huge! Giant formations of rock were abundant near the areas scoured by the creek over thousands (millions?) of years.  You reach the Lake first where the color of the water can be quite striking and a 20-foot waterfall tumbles into it. Perhaps it was the clouds or the angle of our viewing, but we didn’t get to see the best color that day. People are forbidden from swimming in the lake (you could easily be carried over the lower falls from the lake).

There are two paths down to the base of the main falls. The first trail (called the Old Lula Falls Trail) is steep and difficult. The newer one is longer and more manageable but requires you to scramble over quite a few large rocks. We took the new walk down and the old trail back up.

There can be quite a spray from the 120-foot falls but if you move around you can find some dry places. Lots of people like to get close to the falls and even stand under them. We watched from afar on this visit. It was a lively place, full of families having fun. If you want to get wet, bring a suit and drip dry yourself on the return hike to the parking lot.

The 120-foot falls

Sign at the gated entrance

Beyond Black Swallowtails

Black swallowtail, male

I participate in a number of groups on Facebook geared towards supporting pollinators and increasing your wildlife habitat at home. These are wonderful groups with people showing pictures of their flowers and the insects that visit. The thing that kills me (yes, this is my rant of the summer) is the misconceptions about swallowtails and the usage of parsley/fennel/dill.

First of all, not every ‘swallowtail’ is a black swallowtail, so don’t use the term ‘swallowtail’ unless you really are speaking in general. In Georgia, we have a number of other native swallowtail butterflies: Eastern tiger swallowtail, Giant swallowtail, Palamedes swallowtail, Pipevine swallowtail, the tail-less Polydamus swallowtail, Spicebush swallowtail, Zebra swallowtail, and even the red-spotted purple looks like a swallowtail that lost its tails.

Tiger swallowtail: female dark form (left) and male (right)

Second, these other swallowtails have vastly different food preferences as a caterpillar. Several weeks ago, someone posted about raising pipevine caterpillars and what to do if she ran out of pipevine leaves. Another person responded to get some parsley or fennel from the store because “swallowtails love it.” No, I’m sorry but pipevine swallowtail caterpillars won’t eat any plant but a plant related to pipevine (Aristolochia).

Giant swallowtail

Tiger swallowtail: female yellow form

Pipevine swallowtail

Spicebush swallowtail

So, let’s turn this rant into a teaching moment. Here is a list of native host plants for all types of swallowtail butterflies in Georgia. If you’d like to support all types of swallowtails that frequent your area, include some of these plants in your garden and landscape:

Black swallowtail – plants in the Apiaceae family: Angelica, Thaspium (meadowparsnip), Zizia (golden Alexander) and many others (but these are the ones generally sold) as well as non-native relatives like parsley/fennel/dill.

Eastern tiger swallowtail – Liriodendron (tuliptree), Fraxinus (ash), Magnolia (sweetbay magnolia primarily), and Prunus (cherry).

Giant swallowtail - plants in the Rutaceae family: Ptelea (hoptree/waferash), Zanthoxylum (pricklyash also called Hercules’s club) and others as well as non-native citrus relatives.

Palamedes swallowtail – Persea (redbay ); this is a deep south butterfly, normally found in coastal regions where its host is indigenous.

Pipevine swallowtail – Aristolochia (pipevine) and Endodeca (Virginia snakeroot). See my earlier blog on finding pipevine caterpillars on Virginia snakeroot this year.

Polydamus swallowtail– like the pipevine swallowtail: Aristolochia (pipevine) and Endodeca (Virginia snakeroot); this is also a deep south butterfly.

Spicebush swallowtail – Lindera (spicebush), Persea (redbay), and Sassafras.

Zebra swallowtail – Asimina (pawpaw).

Red-spotted purple – Prunus (black cherry) and Salix (willow).

Red-spotted purple

Zebra swallowtail

So when you’re talking about butterflies, please be specific. Their life literally depends on your getting it right when it comes to feeding their caterpillars. And if you want a lot of different butterflies making babies in your yard, please be aware that it takes a lot more than parsley/fennel/dill.

Id tip for dark swallowtails: I find that trying to get a look at the coloration and patterns (dots vs. stripes) on the abdomen is very helpful. I learned about this from this blog post which has excellent pictures of dark swallowtails.

At first, I thought this dark butterfly was a dark form of the Eastern tiger swallowtail because the wings were so muted. In looking at my pictures, I could see a spotted abdomen which the tiger swallowtail does not have. Another picture of the spread wings allowed me to id it as a spicebush swallowtail, but checking the abdomen can narrow down the possibilities.

Declare Independence from the English Ivy

Residential yard in Roswell, GA

We separated from the English monarchy over 200 years ago but some people are still being oppressed by the English. Their landscapes have areas smothered by English ivy.

In driving around the suburbs of Atlanta, I’m always disappointed to see how many homes still have English ivy growing in large swaths, like thick green carpets. It also seems to have a copycat effect - some neighborhoods have quite a few yards with it.

I realize that some homeowners inherited the plant from the previous owner, and it has now grown to an intimidating blob, snaking up trees and swallowing small benches and maybe even slow-moving pets.

There are a few consequences of having it that homeowners should be aware of:

• The leaves hold water and the damp ground underneath is a breeding ground for mosquitoes.

• Vines that climb trees produce flowers and fruit, allowing this plant to spread to neighboring properties (forcing your neighbors to deal with it). I occasionally find seedlings in my yard.

• The dense groundcover suppresses native vegetation, creating a monoculture that reduces bug diversity (think: fewer butterflies and moths) and creates a correlating downward pressure on bird populations which feed on bugs (only a few can eat the mosquitoes that English ivy supports).

A very manageable section for removal

So, in the spirit of the Independence Day that we just celebrated, are you ready to declare your independence from this foreign invader? The following tips come from two folks. One is a friend of mine who has successfully battled it in her own yard. The second is a landscape architect who helps clients that want to remove ivy and incorporate more native plants.

Many folks are dealing with English ivy that has been used (at least initially) to hold a slope. My friend Sheri says that being ready to plant is important in a slope situation. After learning that lesson on one area where washout subsequently occurred, she was ready the next time. For a shady area near the house, she first collected approximately 100 Christmas ferns (Polystichum acrostichoides) from plant rescues with the native plant society. She then worked sections of the slope, loosening by hand the roots of the ivy and then rolling it into a mass and tying the cleared ivy with twine for disposal. Each cleared section was then planted with ferns immediately. She only cleared as much in a day as she could replant. The project took several months.

Leah Pine is an Atlanta-based landscape architect who has clients who have recognized that English ivy doesn’t help the local ecosystem.  Her recommendations include:

• Remove the ivy from trees by cutting them about 6' above the ground and removing the ivy from that point down (pulling it out of the ground). Be careful not to cut into the cambium layer on the tree.

• Small areas: Remove small areas of ivy on the ground by hand pulling. Note: Wear protective gear in any of these steps when removing the ivy as English ivy sap can irritate bare skin similar to poison ivy.

• Large and sloped areas: Remove by using weed whacker to remove the thick leaves of the old growth. When the plant re-sprouts with fresh, tender leaves: spray them with herbicide. Note: Don’t bother spraying old leaves as their tough coating won’t allow for much absorption. Repeat this step several times over several months, allowing the roots of the ivy to continue holding the slope while the plants die.

• To minimize erosion on sloped areas as the ivy roots die, clear a few small sections completely (pull out roots) and plant shrubs or small trees and mulch around them. This also lets you have a little planting fun while working on the bigger area. As you have time, clear new small areas.

• Follow up! English ivy is not a ‘once and done’ plant. Small pieces of root may re-sprout and seeds may germinate. Be aware and pull them out as they appear (don’t wait until it is overwhelming again).

This slightly sloped area has enough trees to hold the slope without the ivy

Trillium cuneatum

Once you’ve cleared the ivy, be aware that suppressed plants/seeds might appear/sprout. Carefully examine what comes up – it might be native and it might not be! Be choosy and keep only the good stuff. This trillium on the right is a perfect example of what might reappear when ivy is removed.

And that copycat concept that I mentioned earlier? It applies to removing it as well; once one neighbor starts to remove the ivy, others seem to follow suit.

Thanks for fighting the good fight. With more areas being developed every day, our personal gardens will become some of the last opportunities to support the insects and birds that rely on what native plants bring to the ecosystem by removing invasive plants and allowing our native plants to have the freedom to grow.

Our Native Wild Petunia

Wild petunia (Ruellia caroliniensis) among neighbors 

A small purple flower often peaks out from beneath other plants this time of year (late spring/early summer). Each flower lasts only a day so it seems that if you go back to look for it, it has disappeared. It generally is about 12 inches in height but can be taller, depending on conditions (the deer nip the tops of mine occasionally). I recently found it blooming in a clipped lawn where it had been cut back to about 3 inches! Seeing it in that lawn is just confirmation for me that this has been a very good year for our most distributed native wild petunia (Ruellia caroliniensis).

Native throughout Georgia and into all the adjacent states, this modest perennial is in the Acanthaceae family which frankly contains a lot of plants that I’ve never heard of because only a few members are in temperate regions like ours. They are not related to the old-fashioned petunias that we buy in the garden center. However, one non-native member of the Ruellia genus is sold in stores: Ruellia brittoniana is often referred to as Mexican petunia. It is much taller, may sucker, and is a more robust species; it has escaped cultivation in Florida where it is now listed as a Category 1 invasive plant. It may be listed as Ruellia caerulea, R. simplex, or R. tweediana.

Flowers on Ruellia caroliniensis

Bud with hairy stems 

Carolina wild petunia has opposite leaves and is sometimes called hairy petunia because of the soft hairs on the stems and leaves. The color on the flowers can vary from almost white to purple with many hues in between. The flowers turn into dry capsules which contain small seeds that will be ejected away from the original plant. I have found this plant to be difficult to pull up due to tenacious roots but that same characteristic helps it to be fairly drought tolerant. Since I have found out that it is one of the host plants for the Common Buckeye butterfly (and the White Peacock in more southern areas), I have been more accepting of its increasing presence in the garden.

Georgia has five other native species of Ruellia, including the rare night-flowering wild petunia, Ruellia noctiflora. Keep an eye out for these summer-blooming native perennials.

Plants nipped by deer are a little bushier Ruellia caroliniensis