#TeachingTuesday: Euphorbia, AKA Spurge

Euphorbias are a fascinating group of plants. There are over 2,000 species in the genus Euphorbia, including cactus-like plants such as crown-of-thorns, and well-known flowers such as poinsettias. Many of the species are native to southern Africa, Madagascar, and Central America. One thing they all have in common is a milky white sap containing latex. But we’re not going to talk about the wide range of diversity today– we’re going to focus on just two cultivars, Ascot Rainbow spurge (Euphorbia x martinii ‘Ascot Rainbow’ PP#21,401) and Ruby Glow spurge (Euphorbia amygdaloides ‘Waleuphglo’ WALBERTON’S® Ruby Glow PP 22,200). You’ll notice that both of these plants have numbers after the names. These are plant patent numbers, and it means that propagation of these plants is prohibited without paying royalties to the patent owner until the patent expires. Modern plant breeding is complicated!

Fun fact: poinsettias are euphorbias too! Euphorbia pulcherrima became a popular Christmas plant after being brought back by the first US ambassador to Mexico (Dr. Joel Roberts Poinsett), where they are native. The red “petals” are actually bracts (leaf-like structures), and they turn red after being exposed to 12 hour nights (periods of total darkness) for several weeks.

How to Use Spurges in the Garden

Ruby Glow and Ascot Rainbow spurges do bloom in the spring/summer, but it’s typically the beautifully colored foliage that catches the eye. They tend to stay evergreen in our warm NC and SC climates, so they work well in fall/winter seasonal plantings, perennial borders, or rock gardens. They can be especially effective in container plantings! While technically a sub-shrub, they are often used in annual plantings and composted after the season ends. Because these types of spurge come from a Mediterranean climate, they prefer well-drained soils.

A mixed planting of yucca, spurge, pansies, and ornamental kale.
Photo credit: Suzy Talucci
Mixed planter containing tulips, pansies, spurge, and dianthus. The spurge has the small yellow-green flowers.
Photo credit: Jenna Meeks

ID Tips

Ascot Rainbow spurge is a cultivar of Martin’s spurge (Euphorbia x martinii), which is a naturally occurring hybrid between Euphorbia characias and Euphorbia amygdaloides, originally discovered growing wild in southern France. This means that the Ruby Glow spurge species is a parent of Ascot Rainbow spurge, and therefore they have very similar characteristics.

  • They both have long, narrow leaves arranged in rosettes around stiff stems
  • The leaves are sessile, meaning that they attach directly to the stem without a small stalk in between (called a petiole).
  • The flowers are borne in sprays at the end of the main stem, and are actually very tiny–in the photo below, the red parts are actually the flower petals, and the larger chartreuse parts are actually bracts. This is why spurges appear to bloom for a very long time, because the bracts are much tougher and longer-lasting than true petals would be.

#TeachingTuesday: Dianthus, AKA Pinks or Sweet Williams

Dianthus – Diana Crimson Picotee

Almost everyone has come in contact with dianthus at some point in their lives. The carnations in floral arrangements are a type of dianthus, it’s a popular fall annual flower, and there are also perennial types as well. Dianthus is ancient flower, known to humans for thousands of years, but most of the ones planted today are new hybrids. In addition to the scientific name of Dianthus, these flowers are also known as sweet williams or pinks. It is believed that the color “pink,” actually came from the flower, like the color “rose” refers to the color of the rose flower. Pinks, the flowers, were named for the zigzagged edges of their petals. If you have a family member who sews, you may be familiar with the special scissors called “pinking shears,” which are used to “pink” the edges of fabric to help prevent raveling.

Pinking shears cut a zigzag along the edge of a seam.
Dianthus flowers, or “pinks,” have zigzag edges on their petals.

Maintenance Tips

Sweet williams have a fairly short blooming period, so frequent deadheading is necessary if you want to keep them in bloom. They should be planted in well-drained soils, otherwise they will be susceptible to crown rot and rust. Snails and slugs can pose a problem, so some type of deterrent such as diatomaceous earth may be necessary.

ID Tips

While there are many different species of dianthus, the most common ones for fall annual planting are China pinks, Dianthus chinensis, or a hybrid between China pinks and another variety. Some of the key features to notice in Dianthus species are:

  • Lance-shaped leaves (similar to a blade of grass or bamboo leaf) that wrap around the main stem.
  • Leaves may have a bluish or silvery cast, due to a waxy layer. This is more pronounced in other Dianthus species.
  • The flowers have 5 fan-shaped petals, and tend to be quite flat. The edges of the petals have a “pinked” appearance, ranging from a slight zigzag to deeply fringed petals resembling eyelashes (check out Dianthus superbus).
  • Flowers range in color from white, pale pink, and lavendar, to brilliant and intense shades of hot pink, red, and fuchsia.

#TeachingTuesday: Pansies & Violas

Wow, it has been a tough start to our fall flower season! Last week we broke multiple heat records, and had both the hottest day of 2019 and the hottest latest day of the year of all-time. Super weird for October… Anyway, our crews pushed through, planting pansies, violas, snapdragons, kale, ivy, heucheras and more! Now that the hot weather seems to be moving on, hopefully both the crews and the flowers will be happier this week.

This week, I’m going to explain some differences between pansies and violas and show some pictures of the gorgeous plants we’ve been installing!

Installation underway!
Photo credit: Bobby McNary

Pansy or Viola?

Pansies (Viola x wittrockiana) and violas (Viola tricolor) look very similar, and are both members of the violet family. The biggest difference is that violas have much smaller blooms, and have more blooms per plant. They grow not quite as tall as pansies, and can have a more spreading or trailing habit, whereas pansies typically grow in clumps. Violas, also known as Johnny-jump-ups, often self-seed and will grow back in unexpected locations, not necessarily where they are desired. Pansies do not typically self-seed, or at least not to the degree that violas do.

Pansies and violas typically survive NC winters pretty well. They are some of the toughest cold-weather flowers. However, violas are even a little tougher than pansies, so if you are concerned about cold weather, violas may be the best choice. They are also a little more shade tolerant than pansies.

Maintenance Tips

In order to keep pansies and violas looking their best, they need to be deadheaded pretty frequently, at least once a week for best results. If they are in a pot by your front door, you may be able to quickly remove the spent flowers and seedpods everyday. To deadhead properly, you must remove the entire flower stalk down to the base where it sprouted. If you only remove the flower at the end of the stalk, the plant will continue to waste valuable energy and nutrients keeping the stalk alive, even though it will never produce another flower.

In very large areas, such as plantings in large commercial areas or along roadways, deadheading is not usually necessary because the flowers are being viewed from farther away. However, they may require additional fertilizer (low in nitrogen) to stay in bloom.

#TeachingTuesday: Best Perennials for Pollinators in Raleigh-Durham, NC

We started our fall flower rotation yesterday, so our training for the crews this morning focused on how to fill out the paperwork correctly for each installation, and a quick review of the plants we covered over the last three weeks. So, while we wait for some gorgeous pictures of the fall flowers to start coming in from the field later this month, I wanted to do something a little different today.

Perennial garden with a mix of over 125 different species and cultivars.

Today I am showcasing pictures from some perennial gardens that I designed last year, so you can see how perennials change to offer something new each season (although unfortunately I don’t have any winter pictures yet–Coming in January?). The perennials shown are growing on a property in the Deep River Triassic Basin, which means the soils are primarily shrink-swell clays in which it is very challenging to grow plants and build structures (see image below).

Image Source: NC Department of Environmental Quality

Gardeners in NC are very familiar with the challenges of growing perennials in our area–the hot, humid summers, challenging clay soil, periods of extreme drought or extreme wet, and winter temperatures that seemingly fluctuate between the 70s and 20s daily. I hope you can find hope and inspiration for your own garden in the photos I share in this post.

Growing Conditions

These images show perennials that have been established approximately 14 months in this location. Some were transplants, but most were 1-gallon size container-grown nursery stock. The soil was amended with organic matter prior to planting, and the beds are mulched with leaf mulch, which continuously adds more organic matter to the soil and allows for easier regrowth in the spring (shredded wood mulch can form thick mats that are difficult for perennials to sprout through). There is an irrigation system in place to provide regular water, but there are dry and wet microclimates within the gardens.

Perennials: Cultivars and Combinations

Spring is not the showiest time of year for perennials, but if you layer in some early bloomers, you can play up the softer shades and textures of green growth. Adding some small evergreens, such as lavender, rosemary, boxwood, or Japanese serissa can help create structure.

In summer, many perennials are in full bloom and pollinators are at their most active. Make sure to provide host plants as well as nectar plants. Don’t worry too much about removing the spring flowers that are starting to brown out; even the brown dried flowerheads or seed stalks can have a very attractive shape or texture.

Echinacea Species & Cultivars:

  • Echinacea tennesseensis
  • Echinacea purpurea ‘Kim’s Knee High’
  • Echinacea x ‘Harvest Moon’
  • Echinacea x ‘Pow Wow White’
  • Echinacea x ‘Cleopatra’
  • Echinacea x ‘Pow Wow Wild Berry’
  • Echinacea purpurea ‘White Swan’
  • Echinacea x ‘Sombrero Sandy Yellow’
  • Echinacea purpurea ‘Magnus’ (this is my best guess–they were transplants)

Salvias are perhaps my favorite fall perennial. Mexican sage (Salvia leucantha) and black and blue sage (Salvia guaranitica ‘Black and Blue’) are only borderline hardy in this area, in fact many plant reference guides list them for zones 8-10. But North Carolinians are often lucky when pushing the envelope with more tender plants, since the Triangle is within the transition zone of 7b/8a. In a brutal winter, these might not survive, but it’s certainly worth it to try.

Out of the fall group, the one that surprised me most was Helianthus salicifolius ‘First Light’, the willow-leaved sunflower. It exploded with flowers when everything else was starting to slow down, and the stalks did a great job staying tall and upright. In a world where it seems like available cultivars grow more compact and dwarfed every year, it’s refreshing to find something tall that can create a wow-factor at the back of a border. It’s also a great nectar source for butterflies and bees, and if you leave the dead flowerheads, birds will eat the seeds in late fall and winter.

I will certainly try to get some good winter pictures as well. For now, I hope you feel inspired! Remember, fall is the best time for planting…

Happy Fall!

Note: Thanks to Herbie Champion for taking all of these great photos!

#TeachingTuesday: Acorus gramineus ‘Ogon’, Golden Variegated Sweet Flag

Our evergreen centerpieces for the fall flower rotation have arrived! Golden variegated sweet flag, or “ogon grass” is front and center.

The Myatt team is gearing up for the fall flower rotation, which starts this Monday! In preparation for that, we focused on Acorus gramineus ‘Ogon,’ or golden variegated sweet flag (also called ogon grass) in our training today. These make beautiful centerpieces for fall planters because of their bright chartreuse coloration, something you don’t see too much in the fall and winter. Contrary to the nickname “ogon grass,” sweet flag is not a type of grass, but rather a plant which is completely separate from all other monocots (grass-like plants). For the plant geeks like myself, sweet flag is a particularly fascinating plant–it’s the oldest surviving line of monocots known to science. You could say that Acorus is the ginkgo of grass-like plants. The name “sweet flag” refers to the pleasant aroma the leaves give off when crushed. In medieval times, sweet flag leaves were cut up and scattered on the dirt floors to make them smell better, and ancient Egyptians used Acorus calamus in their perfumes. Native Americans used a native variety of sweet flag, Acorus calamus var. americanus, in ceremonies and medicines. The golden-leaved Acorus g. ‘Ogon’ cultivar is much newer; the natural species are simply green.

Cultivation Tips

As far as cultivation, sweet flag prefers very moist soil, and can actually grow in up to 4″ of water! It’s great for wet, boggy areas, but this particular variety is not native to the US, so avoid planting it in natural waterways where it could spread and become invasive. It certainly does well in planters as long as they are kept moist. It grows well in full sun, but does not like the heat, so afternoon shade is a must here in the south. If it’s too hot and the soil dries out, the leaves will scorch and start to turn brown. Because sweet flag is a little slower-growing, we don’t typically prune it in the late winter, unless there is a lot of wind scorch. Maintenance-wise, think of it more like a sedge than a grass.

ID Tips

Sweet flag looks like a grass or sedge from a distance, but up close there are several key differences:

  • The leaves are flat like a grass, but grow in a fan shape at the base. It looks extremely similar to Iris pseudacorus, yellow flag. In fact, the specific epithet, “pseudacorus” actually means “false acorus.” In the 1400’s, several herbal guides confused the plants and had incorrectly labelled woodcuts.
  • An easy way to tell sweet flag from yellow flag is in late spring-early summer. Sweet flag does not usually flower unless it’s growing in water, and the flower looks a little like a cattail stalk. Yellow flag has beautiful yellow iris blossoms.
  • The leaves do not have a crease in the center like grasses and sedges do.
Notice the strong fan-shaped base of the leaves.

#TeachingTuesday: Carex rosea, Rosy Sedge

Going into fall, we always like to review different Carex species with our crews. One reason is that we use carex in our fall container plantings, and another is that we want to prevent any accidental cutbacks. The genus “Carex” is made up of grass-like plants called sedges, and although they look like grasses, they grow in different conditions and require different maintenance. Carex looks great in a container because it adds a full, yet delicate texture that moves like a waterfall in the wind. It comes in many different shades of yellow and green, with variegated types as well. On some, the inflorescences (seedheads) are hardly noticeable, and on others they are somewhat attractive. Today, we will specifically look at Carex rosea, the rosy sedge.

Rosy sedge is native to North America, and grows naturally in bottomlands and deciduous forests. It is often found in damp areas such as along streams and ponds, or rocky crevices. It grows in clumps, but will spread slowly by rhizomes (thick roots, like in daylilies) in a favorable environment. This plant is great for shade gardeners, because it will tolerate both wet and dry soils, and it can be used in rain gardens. It can also be grown as a lawn alternative or ground cover (but don’t mow it like grass!). The foliage is a nice medium to dark green, slightly shiny, and fine-textured. The “rosy” part of the name comes from the rosy tint on part of the seedheads.

Maintenance

Maintenance for rosy sedge is next to non-existent! It doesn’t generally need any trimming, unless significant browning occurs in winter. Avoid planting in very windy locations and make sure the plants receive enough water during winter to avoid excessive browning.

ID Tips

  • The leaves of rosy sedge are creased along the center, causing a ‘V’ shape when cut in cross-section.
  • Rosy sedge has very narrow solid green leaves, quite similar to Carex pennsylvanica. Sedge leaves taper gradually to a very long, thin, wiry point which sometimes curls.
  • Most sedges have small, brown, tufty seedheads, and what sets rosy sedges apart is the white fluffy tufts on a rosy brown base.

#TeachingTuesday: Japanese Maple

We took a short break from the blog this summer, but are happy to be back this week with one of our favorite trees–the Japanese maple, Acer palmatum. This species has an incredible variety of sizes, colors, leaf shapes, and habits. Ranging in height from tiny dwarfs up to medium-size trees, similar to a redbud or dogwood, Japanese maples also come in weeping or upright habit. While leaf color and texture in the summer and fall are some of the most recognizable attributes, the architecture of the truck and branches are stunning year-round (but most noticeable in winter and spring), making this a truly 4-season addition to the landscape.

Note the beautiful twisting structure of the branches.
Photo credit: Jeanne Wilkinson
JCRA Photograph Collection

Pruning

Japanese maples require very little pruning. They should never be sheared or topped, as this will ruin the structure of the tree. The only pruning required is occasional selective pruning to remove branches that are diseased, crossing or rubbing on other branches (this can create a wound where pathogens can enter), or need to be removed to increase air or light infiltration (thinning). When in doubt, err on the side of caution or ask a professional. Remember that you can always prune a branch later, but you can’t put it back once you’ve cut it!

ID Tips

  • The leaves of Japanese maples have incredible variety, as you can see above, but they will always grow in opposite pairs along the stems, and will always have 5-11 palmate lobes (lobes that radiate from a central point, like fingers from a palm). Sometimes, the leaves will appear finely dissected, or lacy, especially on weeping varieties. Compared to other species of maple, the leaves are smaller, and the lobes are more delicate, pronounced, and pointed. See images above.
  • The seeds of maple trees are a type of seed called “samaras” and you probably called them helicopters and played with them as a child. Japanese maples typically have pink to red samaras, and they are smaller than other species of maple. See below.
  • The trunk of a Japanese maple is typically more twisted and has smoother bark than other types of maples. The immature bark is often pale green, but may also be colored coral, pinkish, red, or purple depending on the cultivar.
Acer p. ‘Shishi Yatsubasa’
Photo credit: Maryann Debski
JCRA Photography Collection

Going into fall, be on the lookout for outstanding color from these magnificent trees!

Visit the JC Raulston Arboretum to see an extensive collection of different Japanese maples, like this large weeping specimen (Acer p. ‘Green Hornet’).
Photo credit: Susan Bailey
JCRA Photography Collection