Mike Kwiatek – My Chicago Botanic Garden

Chrysanthemums

You’re in a small suburban downtown in early autumn. The sun hangs low in the twilight sky. The crisp, cold air carries the rich perfume of straw, touched with pumpkin spice and apples.You pull your arms close to your body and cradle a warm drink between your hands. Polyester witches hover over pumpkin-laden lamp posts. Planters overflow with chrysanthemums in assorted colors of bronze, gold, white, and red.

Chrysanthemums, also called “mums” or “chrysanths” have always felt to me like old American flowers. This was the kind of plant that grandmothers flocked to the nursery for, just before the leaves began to turn, as if there were some prehistoric trigger deep in the mind. As traditionally American as they may seem, the chrysanthemum is actually a Chinese immigrant.

PHOTO: A mum cultivar. — Modern varieties of mums are much improved, but some of the original Chinese versions could have had flowers like these.

Cultivated as an herb in China for more than 3,500 years, the chrysanthemum represents nobility and is considered one of the four gentlemen: the pure and defiant recluse that represents fall. For a long time, the flowers were only permitted to be grown by nobility, later becoming the badge for the old Chinese army.

Chrysanthemum seeds passed through Korea and arrived in Japan sometime around the fourth century. In 910 C.E., Japan held its first Imperial Chrysanthemum Show and soon after, this became the national flower and the imperial seal of Japan, or “mon” of the imperial family. At the Festival of Happiness and Nihonmatsu Chrysanthemum Dolls Exhibition celebrations in Japan, plants are sculpted to cascade, form trees, and even form outfits for life-sized dolls.

PHOTO: Life-size manikins dressing in traditional clothing made of chrysanthemums sit in temple. — The Nihonmatsu Chrysanthemum Dolls Exhibition is truly astonishing. By User:Harisenbon (Own work) [Public domain], via Wikimedia Commons

In 1688, chrysanthemums crept into Europe. The reception was not warm. It wasn’t until 1843 when Robert Fortune, funded by the Royal Horticultural Society, set out in search of hardy chrysanthemums from China. Within a few years, the plant experienced a popularity boom, especially in France. In contemporary Europe, countries such as France, Poland, and Spain regard certain types of chrysanthemum as a symbol of death and mourning. It is a cultural taboo in some of these areas to provide them as a gift.

Though chrysanthemums arrived in the United States more than 100 years after their arrival in Europe, their popularity exploded at about the same time. In 1900, the Chrysanthemum Society of America formed and the first exhibition appeared at the Art Institute of Chicago in November of 1902. It has since become a fall classic in America.

Classification and Breeding

The very first mums to be classified were yellow to gold in color (the name comes from the greek words “khrusos” for gold and “anthemon” for flower). Thirteen classes of chrysanthemum in nearly every color (except blue and black) make up the thousands of chrysanthemums that have been bred over the years. Chrysanthemums are classified as irregular incurve, reflex, regular incurve, decorative, intermediate incurve, pompon, single and semi-double, anemone, spoon, quill, spider, brush or thistle, and unclassified or exotic. For a full list with descriptions and pictures, visit www.mums.org/chrysanthemum-classes/.

PHOTO: Chrysanthemum 'Wisp of Pink'. — *Chrysanthemum* ‘Wisp of Pink’ is a stunning brush mum. Photo by Tom Weaver.

Chrysanthemums at the Chicago Botanic Garden

As gardeners know, the emergence of flower buds is an exciting event. At the Garden, we drum up the same excitement by using dark cloth to omit light and simulate short day conditions, which triggers the flowering of chrysanthemums. If the summer is typical and you time it right, you will have flowers right when you want them. With an atypically cool summer this year, they received just the encouragement they needed to flower early. That means that if you’ve been to the Garden in the past few days you’ve likely seen the more than 1,600 mums that we planted in the Crescent and the cascading mums descending from the hayracks over the visitor center bridge!

This year, our wonderful production staff grew 50 cultivars of mums, starting in February, to produce more than 12,000 mums for fall displays! Tim Pollak, outdoor floriculturist, oversees the growing, training, and care of the mums from February until they enter the gardens in September.

Did you ever wonder how we get our mums to look the way they do? Good watering practices, fertilizer, disease management, pinching and…nuts?

PHOTO: Hex nuts dangle from wires fastened to mum branches. — Hex nuts hang off chrysanthemum branches like ornaments on a Christmas tree.

PHOTO: Garden mums in bloom. — This year there are four different mums planted in The Crescent.

To train our cascading mums, we attach hex nuts that act as weights to hold down the stems as they grow and harden. This is done weekly by two staff members from February until late August, amounting to more than 400 person-hours from this activity alone!

The mum ball containers you’ll find in the Crescent are the result of the four other techniques used to make our mums look good. Each container contains 18 to 60 plants that are pinched twice a year to obtain those enormous colorful balls!

When you visit, make sure to visit the Elizabeth Hubert Malott Japanese Garden to see the cascading mums, a tradition that has endured for more than twenty-five years!

Also, keep an eye out for mums in the Circle, Sensory, and English Walled Gardens, as well as a new fall feature in the Heritage Garden.

Grow Your Own

Fall planted mums rarely survive winter because their root systems aren’t well developed. Start with healthy, hardy mums in spring, after danger of frost has passed. Plant them somewhere that they’ll get at least three hours of sun. If you want bushier mums, pinch once in early June and later in mid-July. The later you pinch mums, the later they flower, so if you have a cool summer and want later mums, give an extra pinch in the beginning to middle of August. If you wish to fertilize, one to three times throughout the season will be enough for most mums. As for which mum to plant? Tim Pollak suggests the Igloo series.

Underutilized Native Shrubs

Sometime around midsummer, we all look at our yards, filled in and blooming, and think about designing something new, dividing plants, or perhaps creating a new hedge.

Attractive native shrubs are often overlooked—and occasionally hard to come by in local nurseries and garden centers—but they are well worth the effort to find. Already adapted to our particular climate and ecosystems, natives simply do well here—and look spectacular.

Here are five options to consider.

Chokeberry (Aronia sp.)

With a name like chokeberry, people aren’t exactly chomping at the bit to plant this native shrub. It’s unfortunate, because the chokeberry is one of the best shrubs you can grow in Illinois.

PHOTO: Closeup of chokeberry fruit ripening. — Iroquois Beauty™ chokeberry (*Aronia melanocarpa* ‘Morton’) is starting to ripen. The beautiful black fruit stays on the plant longer than some other varieties.

Not to be confused with the chokecherry tree (Prunus virginiana), chokeberry (Aronia sp.) is a fruiting shrub that ranges from 3 to 10 feet tall with red, purple, or black fruit. The name chokeberry comes from the astringency or dryness of the fruit, which may be the result of antioxidants.

There are three main species: Aronia arbutifolia (red chokeberry), Aronia × prunifolia (purple chokeberry), and the most common, Aronia melanocarpa (black chokeberry).

Aronia is an all-season plant. In spring to early summer, the plants become covered in white, apple blossom-like flowers for several days to weeks. The glossy green foliage holds up against extreme heat and drought, and in fall, these great landscape shrubs produce red, purple, or black fruit in combination with orange to red-scarlet fall color.

The fruit attracts birds, though this may often be as late as February depending on Aronia species, food availability, and the density of your bird population. The fruit is also eaten by humans and is popular in Europe. Containing more antioxidants than blueberries and easier to grow, it’s a health food that you should definitely consider adding to your diet! Sweeten the fruit with honey or sugar to make a jam or syrup. I recommend ‘Viking’ for less astringent fruit that is good for harvesting. If fruit doesn’t interest you, consider ‘Professor Ed’ or the Chicagoland Grows variety ‘Morton’, both of which have ornamental fruit, stay somewhat small, and have excellent fall color. Aronia also takes well to renewal pruning if you wish to keep a larger variety at a smaller height.

Buttonbush (Cephalanthus occidentalis)

PHOTO: Closeup of buttonbush in bloom. — Buttonbush (*Cephalanthus occidentalis*) flowers are attractive, unique, and somewhat unworldly. These are growing by the water in the Lavin Evaluation Garden.

Wouldn’t you want something called buttonbush in your yard? The white, butterfly-attracting flowers are arranged in little celestial spheres that are 1 to 2 inches in diameter, emerging between late May and late July (depending on the region). After the flowers have finished blooming, spherical seedheads remain on the plant, providing winter interest. Buttonbush tolerates well-drained soil well, but loves it wet—making this an excellent choice for a rain garden plant!

They can grow fast—a 6-inch shrub can easily grow to 5 feet within a few years, and can reach up to 15 feet when fully mature! These shrubs also take well to renewal pruning, if you’d like to keep them short. They typically have a good rounded habit, but if you would like more uniformity, prune them in late winter or early spring.

Sweet Fern (Comptonia peregrina)

PHOTO: Sweetfern in the fall. — Sweet fern (*Comptonia peregrina*) leaves turn russet in the fall. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons.

Use this plant if you want a unique-looking shrub that can tolerate poor—even salty!—soils. Sweet fern has deeply notched, glossy, fern-like leaves that have a sweet fragrance when crushed. It grows to be around 5 feet tall and 3 feet wide with a nice upright rounded habit, but sweet fern can produce large colonies if left to grow wild.

The flowers and fruit won’t make a huge impact in the garden, but the catkins and fruit may be left as one of those subtle garden curiosities you need to go looking for. The leaves are edible, and are sometimes used for tea as well as insect repellant. These shrubs love part shade to full sun spots, and tolerate drought well.

If your soil is fairly alkaline you may wish to avoid sweetfern, though they will tolerate a degree of alkalinity.

My next pick is another “sweet” choice for the native home garden:

Sweet Gale (Myrica gale)

PHOTO: Sweet gale catkins. — Sweet gale’s (*Myrica gale*) catkins are certainly attractive, if not particularly showy. You can find a hedge of them in the Native Plant Garden, near the patio.

If you’ve got a sunny to somewhat shady wet area, consider sweet gale for your garden. This native shrub prefers moist areas, but tolerates dryness and even some salt. It even fixes nitrogen in its roots, which can help improve the soil. The plants have an attractive mounded, candelabra-like habit, becoming 4 to 5 feet tall in the landscape. The leaves, which are a glossy dark green to gray-green, are fragrant when crushed. The branches, leaves and cones can be used like hops in brewing beer, and were used extensively before hops were widely available. Though sweetgale is native to North America, the species is also native to northern and western Europe, so it appears in European folklore and carries a history of use as a dye, insecticide, tea, and more!

The flowers appear in summer and are not very showy, but the fruit that comes afterward offers a food source for yellow-rumped warblers on their way south.

New Jersey Tea (Ceanothus americanus)

PHOTO: New Jersey tea plant on the green roof. — New Jersey tea (*Ceanothus americanus*) thrives on the green roof of the Plant Conservation Science Center.

New Jersey tea is one native shrub that I hear recommended over and over again, but I can’t recall a time I’ve seen it in a landscape outside of public gardens.

New Jersey tea is a small deciduous shrub that grows to about 4 or 5 feet in height. This nitrogen-fixing member of the buckthorn family grows in open woods and produces leaves that can be dried and used for tea. In fact, its leaves were often used as a tea substitute during the revolutionary war—providing a similar flavor to imported teas, though lacking in caffeine.

New Jersey tea does well in moderately well-drained soils, but it develops a deep root system within a few years so it can withstand drought easily once established. It also provides nectar to butterflies and hummingbirds, acts as a butterfly host plant, and provides food for birds. The yellow twigs that remain in winter can be quite showy, and the white, fragrant flower clusters provide interest in summer.

If you want to make a short but attractive native hedge, start with small plants spaced two to three feet apart. You might also consider Ceanothus ovatus for a hedge that will grow to only 3 feet high.

Candling in the Japanese Garden

Have you been to the Elizabeth Hubert Malott Japanese Garden lately? If you have, you probably saw some of the garden staff perching in the branches of the niwaki. We’re not building nests or hiding out; we’re candling.

Niwaki

Niwaki, literally translated, means “garden tree.” Some people think of niwaki as big bonsai, but that relationship isn’t exactly right. Bonsai translates to “tray (or pot) planting.” While we may think of niwaki as big bonsai, we should try to think of bonsai as niwaki in a pot. The purpose of the two arts are the same; they represent the essence of the tree.

If you consider how bonsai and niwaki are styled, they give the impression of age. The trees may be windswept or upright, often with gnarled bark and wide trunks. We achieve these effects by holding branches vertically with string tied to the ground, with fall pruning, and with candling in both spring and summer.

What’s candling?

In spring, we all know things start to grow again: seeds sprout, perennials push out growth from the roots, and trees break dormancy. In pine trees, these shoots of new growth are called “candles.” When we candle, we break off part of the new growth to stimulate growth from lower nodes. (In other plants, we often refer to this as “pinching.”)

PHOTO: Closeup of the tip of a pine branch, showing new growth. — A closeup of this *Pinus sylvestris* shows where the candle was broken last year and where you expect the new growth to emerge.

The result of breaking these candles is that the new growth spreads more horizontally than vertically, and the density of the pads increase, which makes them appear more lush and healthy over time. We never purposely take off an entire candle, because it removes the most actively growing point and takes longer to recover.

Why candle?

The pine shoots that emerge in spring are called candles for a reason: they tend to be very tall, skinny cylinders like taper or dinner candles. If we let this growth continue, the growth from one pad would grow into the next pad within a few short years. By the time this would happen, much, if not all the original pad would be woody, old, and almost impossible to repair. So in order to maintain the appearance of these trees, we need to candle every year.

PHOTO: Uncandled new growth on the Japanese Garden pine trees. — If allowed to grow, these new shoots would quickly take over.

How long does it take?

There are 180 trees in the Malott Japanese Garden trained in this style. Each tree can take anywhere from eight hours to multiple days, depending on the size and on the person who is working on it. Most of the trees at the entrance to the garden will take eight hours for some of our speedier employees. Most days, during our regular hours, you can expect to see between two to five employees in the trees.

Eating Weeds

If you ever find yourself grumbling over the dandelions that make their home in your lawn, or staring angrily at the purslane popping up in your vegetable garden, I have a suggestion for you: make a salad.

You may be familiar with the concept of foraging for weeds. I first became interested in the subject in college, when I realized that free food was everywhere once you knew where to look. (The reality soon set in that most of this “free” food was actually growing on lawns and private property.) Whenever you forage weeds and wild plants you have to be careful that what you take isn’t getting sprayed with herbicides—which is why I recommend only harvesting weeds from your own yard, or places you know have uncontaminated soil (and aren’t sprayed). It’s also very important to know exactly what you’re eating. Sometimes weeds have look-alikes that can be upsetting to the stomach or downright deadly. Others, of course, you can easily recognize from a distance, like yellow wood sorrel.

PHOTO: Yellow wood sorrel in bloom. — Great as a snack or a garnish, *Oxalis* is a tasty edible weed.

Oxalis stricta

Oxalis stricta, also known as yellow wood sorrel or lemon clover, is an annual weed that you can find anywhere…and everywhere. It spreads aggressively from its seedpods—which can explode on contact!

It only takes a brief sampling of the leaf to figure out why this weed is also called sour grass. The plants are full of oxalic acid, which is dangerous to humans in large amounts, but relatively harmless in small doses. The oxalic acid in the plant gives it a wonderful sour taste that makes for an excellent addition to salads. Oxalis grows commonly in lightly to heavily shaded garden areas. Look for them under plants like hostas.

PHOTO: Dandelion blooming in the lawn. — The long, lion-toothed leaves help identify suburban lawn villain *Taraxacum officinale*, but if you ever have a doubt, look for the aster-esqe yellow blooms.

Taraxacum officinale

Taraxacum officinale, or dandelions, are bothersome weeds, but they are truly “gourmet.” Dandelions get their name from their toothed leaves which are reminiscent of lion’s teeth, or as the French would say, “dent de lion.”

In its long botanical history, the dandelion has been used medicinally, but also as food. Dandelion roots, leaves, and flowers are entirely edible. Roasted, the roots can make for a caffeine-free coffee substitute. The young leaves make for bitter but interesting additions to salads. The plants can also be deprived of sunlight until the leaves become pale, which will change the flavor of the leaves to make them more palatable. The flower buds can be fried and eaten, while the open blooms can be used to make dandelion wine!

PHOTO: Purslane poking up through garden mulch. — Keep an eye out for the fairly drought resistant *Portulaca oleracea* in areas where the ground tends to crack.

Portulaca oleracea

Purslane (Portulaca oleracea) is a weed that you can find in sunny garden areas. They have succulent, red to green, low-spreading stems with flat, paddle-shaped leaves and bright yellow flowers. Purslane actually has an ornamental relative called moss rose (Portulaca grandiflora), which have leaves that are more pointed than flat, and much larger flowers. Though they are also edible, why bother when you have purslane growing naturally? Look for purslane in sunny areas, particularly where the ground can get dry. Harvest purslane any time before the flowers appear, because they can become quite bitter after flowering. Purslane is also incredibly nutritious, rich in Omega-3 fatty acids, and high in Vitamins A, C, and E, as well as magnesium, potassium, and iron, just to name a few. Try it raw, or in a stir-fry!

PHOTO: Lamb's quarters in the garden bed. — *Chenopodium* is an easy weed to scarf up while working in the garden.

Chenopodium album

Another common edible weed is Chenopodium album, also called lambs’ quarters, or goosefoot. It will grow in sunny to partly shady areas and is high in Vitamins A and C. Like Oxalis, it also has high amounts of oxalic acid, so remember to enjoy it in moderation. I prefer to eat the young seedlings, which only have two to three sets of leaves. This makes for an easy snack while you’re in the garden.

Steer clear of Chenopodium’s southern cousin, epazote (Chenopodium ambrosioides or Dysphania ambrosioides). Native to Central America, South America, and southern Mexico, this weed can now be found on roadsides in North America as well. While epazote—whose long skinny leaves do not resemble a goosefoot—is used medicinally for a number of purposes, high doses can can cause severe dermatitis or allergic reactions.

PHOTO: Spiderwort in bloom. — *Tradescantia* is more of a beautiful garden edible than a weed.

Tradescantia

As our final edible weed, I debated including Tradescantia, or spiderwort, in this list. Though it can spread in the garden, it is not anywhere as aggressive as the other weeds in this list. It is also commonly grown for ornamental purposes. Chicagoland Grows’ Tradescantia ‘Tough Love’ is a reddish-purple-flowered cultivar.

The wild plants vary a great deal in size from 1 foot to 4-5 feet tall, depending on species. The small, three-petaled flowers are often blue, but also come in purple, pink, and white. The name spiderwort may come from the fuzzy, webbing-like stamens of the flower, or from the way the mucilaginous substance in the stems will form thin, web-like strands when broken. If you’re planning on eating this one, peel the leaves off the stem and cook them like asparagus. You can also chop up the stems (or leaves) and fry them. But don’t stop there—the flowers are also tasty when raw. Since they usually last for just one day, you don’t have to feel guilty about eating them either! Plus, since they’re native plants used to grazing animals, they can take the abuse!

Strawberries

When I was 8 years old, I traveled with my family to Przysietnica, Poland, to spend the summer with relatives. My grandparents’ farm was the home base for my adventures with cousins and siblings. We spent hours in the breezy northern hills, picking the sweetest strawberries I ever had. They grew wild and tasted like candy. We often brought some back to share with the family, but there is nothing quite like a strawberry fresh off the plant.

PHOTO: Blooming strawberry plant in the garden. — First described by the ancient Romans, strawberries were first cultivated in gardens in the 1300s.

The Cultivated Strawberry

The garden strawberry is the strawberry we most often think of when we think of strawberries. This is the strawberry from the clear plastic boxes you find at the grocery store. This strawberry is Fragaria × ananassa, which has only been around for about 260 years, and has undergone a lot of breeding in that time.

Fragaria × ananassa is actually a cross of the Chilean and Virginia (or wild) strawberry, which arrived in Europe in 1712 and 1624, respectively. The hybrid plant was discovered in the 1750s and recorded in 1759 by Philip Miller, a famous English horticulturist. He referred to it as the “pine strawberry” for its taste, which was similar to pineapple.

If you’re taken aback by this assessment of flavor, you’re not alone—the modern garden strawberry has undergone a great deal of breeding, which improved firmness but did little for its taste. Some of the modern breeding programs are working to fix this problem.

Fragaria × ananassa is not the only cultivated strawberry on the market. There are more than 20 species of strawberries worldwide, with only a small portion of those being grown in gardens for eating. Some of the popular species include the musk strawberry (F. moschata), the alpine strawberry (F. vesca), the Chilean strawberry (F. chiloensis), the Virginia strawberry (F. virginiana), Fragaria nipponica, and Fragaria viridis. Most of these strawberries originate in Europe (Fragaria nipponica is Japanese in origin); the Chilean and Virginia strawberries are the only cultivated New World species. While there are many edible strawberries, these tend to be the most popular.

PHOTO: Rows of strawberry plants mulched with (what else?) straw. — Strawberries planted in rows and left to their own devices will spread wildly within a few years.

Biology

Do you know how the strawberry got its name? The popular theory is that strawberries are so named because they are cultivated on straw. The truth is, strawberries were named before straw was ever cultivated. Have you ever seen strawberries growing? They spread by stolons, or above-ground roots. These stolons reach out, find a good moist spot away from the parent, and put out roots, producing a new clone of the mother plant. In this way, a single cultivar of strawberry can reproduce itself dozens of times and still be identical or nearly identical to the mother plant. The stolons that give rise to new strawberries are called “runners.” This habit of growing is what gave it its name; strawberries tend to be strewn (spread) about.

It’s generally accepted that strawberries will either produce runners or flowers. Though sometimes producing both simultaneously, the energy is usually dedicated to one task over the other. This is why there are three main types of garden strawberries: ever-bearing, day-neutral, and June-bearing. Strawberries tend to be June-bearing by nature, which means you’ll harvest your fruit in late spring to early summer. Though you sometimes end up with a second crop in fall, the June-bearing strawberry will produce runners for the rest of the year. Ever-bearing strawberries prefer to put their energy toward making fruit, so you’ll end up with few runners and strawberries several times per season. Day-neutral will produce strawberries continually throughout the year, and create the fewest runners.

The white tissue under the pistils is what swells into a red juicy strawberry — The white tissue under the pistils swells into the sweet edible “fruit”

“Fruit”

Did you know that a strawberry isn’t a fruit? It’s an “aggregate of achenes on a swollen receptacle.” Achenes are those little specks on the surface of the strawberry; these are the true fruit of the strawberry. The achenes break apart much the way that sunflower seeds do. An aggregate refers to a cluster or grouping, and the receptacle is the part of a flower that bears the sexual organs.

Seems complicated? Try this: cut a strawberry flower in half and look inside.

The female parts of the flower (pistils) are near the top center of the flower with the male parts (stamens) forming a ring around the outside. When the flowers are pollinated, the area under each pistil swells and turns red. When the whole flower is pollinated, you end up with a perfectly red strawberry.

VIDEO: Time lapse of strawberry fruiting process. — Time lapse of a strawberry, flower-to-fruit, by Tomas ‘Frooxius’ Mariancik.

Humans have known about strawberries for hundreds of years, but strawberries only became commercially common within the past century, thanks to refrigerated trucks and breeding programs that gave strawberries their firmness. Ever since, they have been one of the top ten favorite “fruits” in the United States.