"Perennial Ageratum" - Invasive Alert

When I moved into my first home, I begged for a start of “Perennial Ageratum” from my mother’s garden. She warned me to “be careful what you ask for” and said that the plants spread “like wildfire.” I assumed that the plant could not be THAT bad, since she had acquired her start from her own mother’s yard. Mistaken assumption.

Perennial Ageratum or Blue Mist Flower (Eupatorium colestinum or Conoclinium colestinum) resembles Ageratum, a well-behaved annual with fuzzy blue powder-puff blooms. Blue Mist is a hardy perennial that spreads aggressively via underground rhizomes and self-seeds. I. When driving through the countryside in September, I often spot it growing in ditches and near old home sites. It can be considered a weed because of its spreading tendencies.

The 24” tall plants will thrive in sun or shade (more blooms in sun), wet or dry, and any type of soil. They will tolerate either drought and soggy wet soils. They are not bothered by insects, disease or deer. Pollinators love them.

In late summer or early autumn, they erupt into a haze of soft blue flowers that look like asters from a distance. I cope with their invasive nature by planting them with other aggressive growers and allowing them to duke it out for ground space. A great combination is Blue Mist and Goldenrod (Solidago). These two bloom at the same time. Add ‘Autumn Joy’ sedum and accent with Mexican Salvia (Salvia leucantha) for a pretty fall combination.

Control the root spread of both Blue Mist and Goldenrod by planting them in plastic nursery pots with the bottoms removed, then sinking those pots into flower beds. Be sure that the top rim of the pots extend slightly above soil surface. This will prevent spreading via roots. Deadheading as soon a blooms fade will help control reseeding.

The photo shows that a tiny seedling can have an impressive root network underground.

Ageratum roots.jpg
Perennial Ageratum flower

Peanut Butter Tree

Clerodendrum trichotomum (pronounced kler-o-DEN-drum trik-o-TO-mum), more commonly known as “Harlequin Glorybower” or “Peanut Butter tree” is considered invasive in some states. It is prone to whiteflies and aphids, and may be troubled with leafspots. It suckers readily. Birds spread the seeds far and wide. The short tree or multistemmed shrub has a loose structure and an unkempt appearance. I grow it anyway.

Why grow something that has multiple issues? Fragrant white flowers appear in summer. When the bloom petals fall, the calyxes remain behind and turn a deep rose. The round seeds are an eye-catching metallic blue. Crushed leaves smell like peanut butter, providing entertainment for young garden visitors. This small tree survives in dry shade but will flower better and have more berries in sun. These benefits outweigh the trouble of pulling out seedlings or cutting off suckers that rise from roots.  The species cannot pollinate itself, so if berries are desired, add a second plant from different parents.

I think Clerodendrums look best when trained to a single-trunk form. The tallest ones in the Mary Snoddy garden are just under eleven feet.  There is a cultivar with variegated leaves, but the leaf coloration tends toward green with only a touch of white, which makes it look more like a sick plant than a variegated one. Clerodendrum trichotomum has a cousin, Clerodendrum bungei with a similar appearance but smells like over-scented soap. The common name is “Cashmere Bouquet.” 

Harlequin Glorybowers are tolerant but, like most other plants, they look best in moist, fertile soil. They are cold hardy in Zones 7-10. The shrub/tree loses every leaf after frost in my zone 7B garden. Its bright seed display fills a flower void in the garden between Crape Myrtles and Sasanqua Camellias, which makes it an autumn standout.

Smells Like Grape Jelly

If you are brave enough to drive around South Carolina with your windows down during fall’s ragweed season, you might catch a whiff of something that smells like grape soda or grape jelly. You might even catch a flash of purple in the sea of green that covers large sections of country and parts of undeveloped city blocks. The green blanket that crawls over anything in its path (trees, tractors, power poles, buildings, shrubs and, I’m guessing, slow-moving people) is kudzu. 

On April 28, 1918, my husband’s great-grandfather recorded in his daily journal, “Planted cudzu vine.” Since we now live on the farm that was then his home, I am thankful he was not successful with the plant that was widely touted to stop soil erosion. Erosion was especially troublesome for large tracts of land that were depleted by repeated crops of cotton. Kudzu was first introduced in the US in 1876, at a Centennial Exposition in Philadelphia that was meant to celebrate our nation’s 100th birthday. During the Great Depression, our government created jobs for workers by paying them to plant acres of the vine. There was no way to know that kudzu would be much more vigorous in the southern USA than in its native Japan. 

Pueraria montana (known by absolutely everyone as ‘kudzu’) has spread across the entire southeastern US. Some jokingly refer to it as The Vine That Ate The South. Kudzu loves southern heat and humidity but is also found as far north as South Dakota and as far west as Washington state. In hot weather, the vine can grow as much as one foot per day. It thrives in any type of soil and never needs irrigation. It may reach up to 100 feet – in ONE season! It kills trees and shrubs by blocking sunlight. It can also strangle trees by girdling their trunks. Current estimates say that two million American acres are covered in kudzu. It is included on every invasive list. The huge tap roots may produce as many as thirty vines growing from a single crown. Vines also root where they touch soil. The pretty purple flowers resemble pea blossoms and smell like grapes. They mature to flat seed pods. 

Control is difficult. Deer don’t seem to care for the fuzzy stems, but goats feed happily. Best results include a combination of herbicides, repeated close mowing, mechanical removal of the root crowns, and prayer. The US Department of Agriculture is investigating biologic controls including a natural fungus.

Hurricane Lily

One of the common names for Lycoris radiata is Hurricane Lily. Other common names are “Magic Lily,” “Naked Ladies,” and “Spider Lily.” Since Hurricane Dorian recently threatened the southeastern US coast, “Hurricane Lily” seems most appropriate. “Magic Lily” and “Naked Ladies” refer to the growth habit. These bulbs put up their foliage in the season opposite to flowering. Those that are in bloom right now push up narrow, grass-like foliage in the spring. During summer, the foliage dies down and naked stems emerge to bloom in September. Some varieties are the opposite, pushing out foliage in autumn and flowering in the spring. “Spider Lily” comes from their long, prominent stamens.

Companies that sell Lycoris bulbs offer conflicting information about planting depth and name pronunciation. Some say Ly-COR-iss; others say LICK-or-iss. Select your favorite. Many sites call for planting depths of 5 inches. Others say that the bulbs should be planted barely under the soil’s surface. I have tried both depths in the Zone 7B Mary Snoddy garden and received much better results from a shallow planning.  

Lycoris bulbs resent being transplanted. It takes a couple of years for them to appear at their best. Be patient. The wait is worthwhile. Bulbs look prettiest when planted in groupings rather than a soldier-straight line. Plant 3-6 bulbs per square foot, spaced 4-6 inches apart, in full sun to partial shade. Flower stems reach up to 18 inches in height. They make long-lasting cut flowers. 

Lycoris are cold-hardy zones 6-10 and are resistant to pests and diseases. Don’t allow pets or children to eat them because of a mild toxicity.

The long curled stamens of Lycoris.

The long curled stamens of Lycoris.

Lycoris have naturalized in an open meadow.

Lycoris have naturalized in an open meadow.

September Garden Checklist

Here is my garden checklist for things to do in the garden this month and other notes for this time of transition between summer and autumn:

  • Perform a soil test and apply lime as directed.

  • Keep an eye out for spider mites on conifers and other shrubs. (see photos)

  • Save seeds from favorite annuals and perennials.

  • Decide which houseplants will move indoors for fall. Trim back to keep them compact. Inspect for insects; treat as needed.

  • Order bulbs and get them in the ground before cold weather arrives.

  • Remove dead annuals and any dead portions of perennials to prevent diseases and keep the garden looking neat.

  • Later this month, plant lettuce and cabbage seed for fall vegetable garden.

  • Divide daylillies and share extras with gardening friends.

Other notes for the month:

  • Shrubs, trees and perennials planted now will have an opportunity to put new roots into warm soil. Don’t forget to water during dry periods.

  • Don’t be alarmed if the innermost needles of conifers turn brown and drop off now. This is normal.

  • Be vigilant about removing weeds. Cool season weeds like Henbit will start to emerge soon. Pull them when they are small, before they have had a chance to bloom and set seed.

  • Do not prune spring-flowering shrubs like azaleas or viburnums. This would be removing the bloom buds they have set for next year.

  • For fescue lawns in South Carolina, now is the time to reseed bare patches.

Spider mites on Holly ( Ilex)  are most obvious in the morning, before sun dries the dew clinging to the webs.

Spider mites on Holly (Ilex) are most obvious in the morning, before sun dries the dew clinging to the webs.

Spider mite webs are obvious on this  Ilex compacta , but a magnifying glass is needed to see the tiny insects.

Spider mite webs are obvious on this Ilex compacta, but a magnifying glass is needed to see the tiny insects.

Moonflower Night Magic

Moonflower (Ipomoea alba) looks like a white Morning Glory on steroids. This heat-loving annual vine is easily started from seed and grows like the wind. It blooms from June to frost in my zone 7b garden. The moonflower’s claim to fame is that the flowers open at dusk and release a faint perfume. The scent attracts night-flying moths and makes it a perfect plant to site near your patio, porch or nighttime entertaining areas. When morning sun arrives, the blooms collapse like parachutes. The flowers stay open later on overcast days.

A single vine will grow to 10-feet tall when provided with a trellis. They can also be allowed to scramble across the ground, but I prefer them to be at nose-level to better enjoy the fragrance. Do not fertilize or you will sacrifice blooms to leaf growth.  They rarely need supplemental irrigation. No need to deadhead, as the spent blooms shed naturally. Flowers can reach six-inches across. 

The accompanying photo shows a pair of vines grown on a 7-foot tower. When the plants start growing vigorously, I guide the soft stems horizontally around the tower so that the entire structure will be clothed with leaves rather than having them clustered at the top and naked near the bottom. Vines twine to climb so they will not damage walls or wooden posts with adhesive feet. 

Moonflower seeds are available in gardener centers and big box stores. The seeds are the size of peas, with a hard covering. I use a pair of nail clippers to snip a tiny hole of this hard shell and soak them in water overnight before planting. Use caution to avoid damaging the “eye” of the seed when snipping. This is where the first root, the radical, will emerge from the covering. The chip-and-soak procedure speeds germination. Start seeds about the same time you start tomato seeds. Any earlier is wasted effort, since the vines grow slowly until night temperatures are warm. Frost kills the tender vine, so it is a summertime pleasure only unless you live in frost-free zones, where they are perennial.

Unlike their Morning Glory cousins, Moonflowers are not invasive. Insects do not bother those grown on a trellis but I have seen evidence of slug nibbles on the vines allowed to trail across the ground.  Because of the large seed size, quick growth and large flowers, these vines are a great plant to start with children.

The overcast morning allowed a photograph before the blooms closed.

The overcast morning allowed a photograph before the blooms closed.

Writing Spiders

Writing spiders (Argiope aurantia) have made their annual appearance in the Snoddy garden. These black and yellow spiders are large and easy to spot. Other common names are zigzag spider, corn spider, gold orb weaver, scribblers and a host of others. The name is pronounced Argiope (ar-JY-oh-pee) aurantia (aw-RAN-tee-a), although I found alternate pronunciations on websites. These spiders are found in all 48 contiguous states.

Argiope spiders build large, elaborate webs that often contain heavier threads that look like X’s or Z’s. This gave rise to the common name ‘writing spider’ and also the folklore that ‘if a writing spider spells your name, you are going to die that night.’ My mother passed that tall tale along to me, so as a child I consulted the webs daily to see if my time was up. (Thanks, Mom!) There are various theories as to the purpose of these heavier threads, known as stabilimentum (attract prey, keep birds from flying into webs, add web stability) but none of them are proven. Parents should teach their children to admire from a distance, since Argiopes will bite if handled. The bite is not toxic but hurts like a bee-sting.

Trivia: In the children’s book Charlotte’s Web, Charlotte was such a talented spider that she wrote entire phrases (“Some Pig”) instead of simple X’s and Z’s.

Last week my husband spotted the remains of what appeared to be another Argiope (just a pair of legs) wrapped in silk in one of our regular webbers. He asked me if they were cannibals. A little research revealed that males have an irreversible seizure after mating and they die in less than an hour. The female wraps him up in silk and stores him on the edge of her web for an afternoon snack.  She selects a location for her web where the likelihood of a meal is high and the chance for disturbance seems low. Once this site is chosen, she will remain there every day. Webs are spun from self-produced silk that is stronger than steel of the same diameter. She tears her web down and reconstructs it every night. Webs can be two feet across. Females are approximately three times the size of males. 

The typical life span of an Argiope is one year.  The female leaves a sack of eggs for posterity and dies with the first hard frost. The eggs hatch within the sack during late fall or winter. The babies (300 or more) emerge in the warmer weather of spring. Any that are not consumed by birds or other predators start the cycle again.  

When I began photographing our resident Argiopes for this blog article, I noticed that they always hang head-down on their webs. When insect prey is snared in the sticky web threads, they move lightning-fast to wrap them up into a “eat it later” package. Occasionally they hold pairs of their legs together so tightly that it appears that they have four legs instead of eight. 

Many people have a fear of spiders (“arachnophobia”) but they are beneficial to the environment and should not be killed. If an Argiope builds her web in an inconvenient location, across your doorway for instance, destroying the web several days in a row will encourage her to relocate to a more hospitable site.

Argiope heads are covered with silvery hairs.

Argiope heads are covered with silvery hairs.

Is she writing YOUR name?

Is she writing YOUR name?

Malvaviscus, Not Hibiscus

As temperatures continue to hover in the 90s, I continue to focus on plants that perform well in heat and humidity. One of the best August performers in the Mary Snoddy garden is Turk’s Turban.

Malvaviscus arboreus var. drummondii has several common names that describe its appearance. “Lazy Hibiscus” and “Turk’s Turban” describe its bloom, which looks very much like a Hibiscus that has not yet opened or a tightly wrapped Arabian turban.

This southeastern native is one of the most undemanding perennials you can grow. While it prefers partial shade, it will grow and bloom well in full-sun, although its leaves may be smaller with more light.  The blooms start appearing in the hottest part of the summer and continue to frost. The ‘arboreus’ part of the Latin name means ‘tree-like.’ The plant average height is 2-4 feet in height, so it is more shrub-like than tree-like. It my Zone 7 garden, it dies to the ground with a couple of hard freezes.

Dead top growth should be removed in winter since new growth will pop up the next season. Sometimes they seem slow to emerge in the spring. Don’t give up – These plants are stalwart. They will thrive in any soil, from sand to clay, acidic or alkaline, wet or dry. Malvaviscus leaves are fuzzy to touch, which helps with their marvelous heat tolerance. Once established, they are drought tolerant also.

Red blooms pop against the medium green foliage, attracting attention from hummingbirds, butterflies and bees. White bloom or variegated foliage varieties are available, too. If left alone, the plants reseed to form handsome colonies. Cuttings root easily when treated with hormone. The plants will root themselves if limbs lay against the soil. You can help with this layered rooting by scratching a stem surface a bit then holding the wounded area against the soil with a brick or rock. Check for roots after twelve weeks. Rooted sections can be cut away from the mother plant and transplanted to another location. Established clumps can be divided with a shovel, but this requires a sharp shovel and a strong foot to push it with.

The Turk’s Turban in my garden is more than 40 years old. It is located in a roadside bed where it gets heat from the street and also from an asphalt driveway. It receives no supplemental irrigation whatsoever and receives shade about two hours during mid-day. It has grown to be a clump 5 feet by 8 feet. The hummingbirds thank us every day. And our deer ignore it completely.

 This is truly a “plant it and forget it” star.

The tightly wrapped petals look like a turk’s turban, hence the common name.

The tightly wrapped petals look like a turk’s turban, hence the common name.

Turk’s Turban mingles with Sedum in a baking-hot roadside garden.

Turk’s Turban mingles with Sedum in a baking-hot roadside garden.

Crocosmias Glow In The Heat

When the “feels like” temperatures are in triple digits, many annuals and perennials slow down or even stop blooming. This makes us appreciate those stalwarts that bloom through the hottest days of the year. One of these is Crocosmia (pronounced Crow-KAHZ-mee-ah).

Crocosmia leaves resemble gladiola or Siberian Iris. The blooms occur at the topmost part of a wiry stem. They last a long time as cut flowers. Blooms are most often red (‘Lucifer’ cultivar) or orange, occasionally yellow. Hummingbirds flock to all shades. They look especially great when paired with blue Salvia.

Crocosmia, sometimes called Montbretia, is a type of bulb known as a corm. Corms are much smaller than true bulbs like tulips or daffodils. They create a new bulb each year to sustain them through cold weather. These storage units stack themselves on top of each other, gradually developing into a loose chain, like a sleeve of Ritz crackers, only much smaller. The bond joining the corms is not strong, so they break apart when gardeners attempt to dig them up to relocate them. The corms left behind sprout into new plants, leading gardeners believe that they spread to the point of invasiveness.

Crocosmias are hardy in zones 6 to 10. They look best when planted in groups of 10 or more. Blooming is heaviest when the clumps of bulbs are divided every three years or so. Because they reproduce readily, many gardeners will be happy to share their divisions. They should be planted in full sun to light shade, in slightly acidic soil. Crocosmias are not browsed by deer or rabbits, and are usually ignored by slugs. A winner!

Orange Crocosmia glow when backlit by sunshine.

Orange Crocosmia glow when backlit by sunshine.

Beetle Mania!

While pulling weeds, I encountered this impressive beetle. It is a female Dynastes tityus. I felt lucky to find one. The grubs and the beetles are both large (grubs can be more than four inches long and adults can reach two-and-a-half inches), which means that they make a satisfying meal for predators such as skunks, raccoons and even spiders. The eggs fall prey to mites and maggots. Their meal-appeal means that Nature keeps populations in check. Please don’t run for the insecticide when you see one of these. The grubs live on decaying matter on the forest floor, so they are not damaging live plant roots.

The adult beetles range in color from green to gold; some have black spots and some do not. They are heavy for their size and strong, hence the common name “Hercules Beetle.” Insect authorities estimate that the Hercules Beetle can lift 100 to 800 times its own body weight. Even on the low end of the scale, that is like a 200 pound man lifting ten tons. 

How do you tell the girls from the boys? Males have C-shaped horns on their heads, used to battle other males when competing for mating privileges. Those horns have led to their characterization as a “rhinoceros beetle.”

 You will note that I handled this girl while wearing nitrile gloves. It wasn’t from the danger of being bitten. They do not bite, but when threatened they exude a nasty smell. This visitor to the Mary Snoddy garden is the Eastern Hercules Beetle. There are others in the same family found in many countries. Some places they are prized as pets. I recommend cats. Or dogs. Or both.

Marvelous Melampodium

Melampodium is one of the hardest working plants in the Mary Snoddy garden. Its butter-yellow bloom color is not at the top of my favorites lists, but all of its other characteristics make it a winner.

It starts blooming when it is only a few inches tall.
It blooms all summer and fall.
It does equally well in beds or containers.
The spent blooms drop off without the need for deadheading.
No need to stake. The strong stems keep it erect.
It thrives in heat and humidity.
It will forgive a little bit of drought.
The plant branches as it grows, making a nice round shape.
It is deer resistant.
It is fairly easy to grow from seed, but plants are widely available in nurseries during April and May. When left alone, it will reseed all by itself.
Bees and butterflies love the blooms.
It is rarely bothered by insects or diseases.

Several cultivars are available. Labeled height range from 10 inches to 24 inches, although mine usually grow a littler taller than the label predicts.

The only drawback to the plant is that the warm yellow color of its flowers does not mix well with pastels. Instead, pair it with bold reds and strong purples. Perhaps I am biased, but I think it looks pretty wonderful with purple-leaf Perilla frutescens here at New Hope Farm.

Melampodium makes an impressive companion to Perilla (left) and Ironweed (right).

Melampodium makes an impressive companion to Perilla (left) and Ironweed (right).

Melampodium in container (4 plants).

Melampodium in container (4 plants).

A single yellow Melampodium makes the colors of Gomphrena, Zinnia and Liatris POP.

A single yellow Melampodium makes the colors of Gomphrena, Zinnia and Liatris POP.

Pretty Purple Ironweed

Here is another easy plant for all gardeners who like purple. Vernonia noveboracensis (pronounced ver-NOH-nee-ah no-vee-bor-ah-SEN-sis), “New York Ironweed” is ideal for hot, humid climates. Please don’t confuse this one with Veronica, a totally different plant.

Ironweed is tall and narrow. It has large clusters of tiny purple flowers mid-summer to late fall. The flowers attract butterflies and bees, so it is perfect for the back of a pollinator garden.  It blooms best in full sun, but will also tolerate half-sun. If the spent blooms are pruned away, the plant frequently will branch and re-bloom. If you forego the deadheading, finches and other seed-loving birds will visit to remove the seeds for you. Mine have occasionally reseeded. Baby plants are easy to relocate.

Ironweed prefers an acidic soil, so don’t bother with lime. They like moist soils that are high in organic matter, but will tolerate less water. Mine are planted in heavy clay soil and do well. The plant’s tolerance for varying moisture levels means it will do well in rain gardens.

Left alone, Ironweed will reach 6 to 8 feet in height. This is a little too tall to fit into the garden beds in the Mary Snoddy garden, so I cut it back by half in mid-May. This delays the flowering a bit, but the plant branches where it is cut back, so I end up with more flowers than if I had left it unpruned. The brilliant purple blooms pair well with most other colors. In this year’s annual bed, I grouped it with Melampodium, a wonderful annual that I will write about next week.

Ironweed dies completely to the ground in freezing weather.  The dead stems should be pruned off. It is perennial in most of the US (zones 5a to 9b). This one looks equally at home in mixed borders and wildflower plantings. Highly recommended!

Angelonia - Summer Snapdragon

Last week I wrote about one of the best long-blooming summer perennials, Purple Coneflower. Today we focus on one of the very best annuals for heat and humidity. Angelonia angustifolia is heat resistant. It will also withstand short periods of drought, but it looks best if given regular water during the hottest part of the year.

Angelonia does well in containers and in ground. It is an annual but will act as a perennial in zones 9b and warmer. Plants are tall are narrow. I pack them densely into containers, where they reach about 24 inches tall with a limited spread. In the ground, they may reach up to 40 inches and will branch to 12 inches wide. They look fabulous planted in large masses.

Angelonias are available in blue, purple, white, rose/pink and a bi-color purple-white combination that I love. The spikes of blooms start opening from the bottom. The old blooms drop off without the need for deadheadling. Once the top-most blooms have opened, snip the entire stem off with scissors. The plant will branch and the new branches will bloom in just a few weeks. They make long-lasting cut flowers if you remember to remove any leaves that will be below water level.

For best blooms, give them full sun and good drainage. If the leaf color starts looking wimpy, give them a drink of liquid fertilizer to restore them to their original medium green. If you neglect them or allow them to dry out completely, cut them back hard and they will regenerate if given water and liquid fertilizer.

Angelonia are great plants for the new gardener. Easy and beautiful!

Purple, bicolor and white Angelonia.

Purple, bicolor and white Angelonia.

Angelonias in a cast iron urn.

Angelonias in a cast iron urn.

Long-blooming Purple Coneflowers

Most perennials have shorter bloom periods than summer annuals. One that flowers for a lengthy time is Echinacea purpurea, Purple Coneflower.  In upstate South Carolina, the first blooms open in late spring (just after Mother’s Day) and continue all the way to frost. Purple was the original color of this prairie native that has been adapted to garden use. Hybridization expanded color choices to rose, orange-red, yellow, pink, magenta,  white and green. The Latin name came from the Greek word echinos, meaning hedgehog, a reference to the spiky orange central cone. The coarse leaves are a bit rough.

Coneflowers prefer full sun. They are heat resistant and will tolerate moderate drought. They are adaptable to various soil types and will grow in zones 3 to 9. They rarely need fertilizer. Cultivars vary in height but average 3-4 feet with a 2-3 foot spread.

Bumblebees and butterflies flock to the flowers. Blooms are long lasting, either on the plant or as cut flowers. Deadheading keeps the plant neater and forces fresh buds to form. I stop deadheading in autumn and allow the spent flowers to remain through winter, offering a seed treat to finches and other birds.  Any uneaten seed self-sow for new plants in the spring but the seeds of cultivars may not be like their parent plants. Seedlings are easily transplanted. Cut dead leaves and stems to ground level in late winter before spring growth begins.

Deer ignore coneflowers but rabbits find them tasty. They are rarely damaged by insects or diseases, but may show occasional damage from aphids, Japanese beetles, powdery mildew or bacterial leaf spots. I have experienced an occasional problem with “aster yellows” but promptly removed the affected plants to avoid a spread to neighboring plants. My two favorite cultivars are ‘Magnus’ which has large, light purple blooms and ‘Kim’s Knee High’ which is only a foot tall. Both look best when planted in masses rather than as single plants.

A bumblebee busy on a ‘Magnus’ coneflower bloom.

A bumblebee busy on a ‘Magnus’ coneflower bloom.

A group planting.

A group planting.

Note the weird green buds inside the purple circle. These deformed blooms are a symptom of Aster Yellows. Remove and destroy the plant to prevent the spread. Aster yellows is a bacteria-like organism called a phytoplasma. It is spread by leafhoppers.

Note the weird green buds inside the purple circle. These deformed blooms are a symptom of Aster Yellows. Remove and destroy the plant to prevent the spread. Aster yellows is a bacteria-like organism called a phytoplasma. It is spread by leafhoppers.

Color Me Confused

Last year I received a gift shrub from a dear friend. The tag said “Blue Mist Spirea.” There was no Latin name included. When I did a little research online to learn the plant’s sun and water requirements, I was astonished to learn that it was NOT a Spirea. Not even close. Instead, this gray-leaf beauty with clusters of tiny powder-blue blooms is a Caryopteris. So why call a Caryopteris a Spirea? Beats me. They are not even in the same family. I can only guess that there was some confusion in the plant breeder’s greenhouse and once the patent was received or the plant tags were printed, it was too hard or expensive to make the correction.

Many garden centers will offer “Blue Mist Spirea,” but you may also find ‘Longwood Blue,’ ‘Beyond Midnight,’ ‘Dark Knight’ and ‘Grand Bleu.’ The ‘Worchester Gold’ cultivar has some yellow to its foliage, but it is not as golden as the name might lead one to believe. It tends to turn more green where summers are hot.

Plant Caryopteris in full sun, in well-drained, lean soil. Too rich a soil produces soft growth that is weak and floppy. It is heat and drought tolerant. The blooms attract numerous butterflies and bees, so site them away from busy pathways and entrances. The shrub naturally forms a nice mounded shape with a fine texture. It is deciduous, losing every leaf when hard freezes arrive. The branches should be pruned hard (down to 12 inches or less) in early spring because blooms occur only on new growth. Pruning will also keep the plant dense and compact. Resist the temptation to trim until spring arrives and new growth starts to show. If you prune in autumn or early winter, the plant may not live through cold weather. Wet soil in winter may also cause plant death.

Caryopteris are easy to grow from cuttings, but many times the plant self-propagates by growing roots wherever a branch touches soil. These rooted branches can be separated from the mother in spring and transplanted to new locations. Caryopteris look pretty when paired with gray-leafed Artemesia such as ‘Powis Castle’ or contrast nicely with burgundy foliage. It also looks fabulous planted next to orange Zinnias.

Caryopteris foliage has a distinctive odor that deer don’t like. Some people describe it as smelling like bell pepper. I don’t agree, but cannot find another comparison that is more accurate. Deer do not browse it and insects do not bother it. This small scale (36 inches or less) shrub is trouble free and should be planted more often. It is hardy in Zones 6-9.

Clusters of tiny blue blooms form along the stems of Caryopteris.

Clusters of tiny blue blooms form along the stems of Caryopteris.

Gloriosa Lily

Glory Lily, Gloriosa superba, is not really a lily but is absolutely superb. It is one of the few vines in the Mary Snoddy garden. When I purchased two odd looking bulbs, the label said they were only cold hardy in zone 8-10. I planted mine in two containers against one of my outbuildings, with plans to move the containers inside before freezing weather arrived. The vines were beautiful, although they did not bloom until late summer during their first year. I forgot to move them to a freeze-proof area, and assumed that I had lost them. That was fifteen years ago. The vines have made a return appearance every year. I believe that the outbuilding provides just enough protection to allow them to survive my zone 7b winters.

 The bulb resembles a fingerling potato or a Jerusalem artichoke, but it is kin to neither. Instead it is in the same genetic family as Colchium, the fall-blooming crocus. When vines emerge from winter dormancy, they grow very quickly. The tendrils at the tips of the leaves curl around whatever is close. I choose to provide a trellis, but they can be allowed to scramble over a shrub. The variety in my garden is ‘Rothschildiana’ which has red and yellow blooms. I have also seen it listed in catalogs as Gloriosa rothschildiana. Blooming starts in mid-June and continues until frost.

 Be prepared for the vines to reach anywhere from 6 to 15 feet. The deeper the bulb is planted, the shorter the vines and the more erect their growth habit. They like an evenly moist soil and full sun. The vines are a bit brittle, so if you plan to train them on a trellis, start while the plants are small and don’t require a lot of manipulation. Avoid windy areas to prevent to vine breakage.

 All parts of the vine are toxic and ingestion may be fatal. Enjoy looking but don’t eat.

Unusual and beautiful.

Unusual and beautiful.

The weathered wood of the outbuilding makes the color pop and the trellis disappear.

The weathered wood of the outbuilding makes the color pop and the trellis disappear.

Nature's Barometer Plant

Rumex sanguineus (pronounced ROO-meks san-GWIN-ee-us) is known by various common names including Bloody Sorrel, Bloodwort and Red-Veined Dock. It is not eye-catching, but EVERY gardener needs this plant! I reserve exclamation points for the most important points, so pay attention. This plant serves as your personal barometer.

Rumex tells the gardener when containers, window boxes or beds are thirsty. I suggest that you plant one in every mixed container and every garden bed as an irrigation alarm. Just like the Peace Lily in your kitchen window wilts when it is dry but then revives when watered, Rumex wilts horribly when it is too dry. Unless you have ignored its pitiful message for days, a little water will make it perk back up in a few hours.

While it is not a visual standout, the red veined leaves make a terrific addition to containers. The rosette clumps of leaves reach 12-15 inches in height. Rumex has a deep taproot; it ignores heat and humidity and will grow in either sun or shade. When you include this barometer in your plantings, you can stroll past your beds and containers and immediately know which ones need water. They are the ones with the wilted Rumex. If the Rumex looks fine, the bed does not need water. If you have numerous or large gardens, this messenger saves you time.

Rumex also works well as a pond-side plant or near your water garden. It spreads happily in damp areas. It is an evergreen perennial in Zones 6-8, although it may be a little tattered at winter’s end. Use scissors to cut off any damaged leaves, and avoid the red sap because it stains fingers and clothes. I have seen recipes for sorrel soups, but have never tried cooking any of my yard plants although I have chewed on a leaf. The taste was tart but lemony and refreshing – and left me with pink teeth.

Rumex is a reliable soil moisture indicator. Allow it to save you time.

A smart gardener featured Rumex next to a golden-leaf Abelia. The deep red veins of Rumex echoed the red stems of the Abelia, a wonderful combination I observed while on the 2019 Master Gardener tour of private gardens in May.

A smart gardener featured Rumex next to a golden-leaf Abelia. The deep red veins of Rumex echoed the red stems of the Abelia, a wonderful combination I observed while on the 2019 Master Gardener tour of private gardens in May.

A tiny Rumex nestled in a basket lets me know when the Lantana need water. The clear filament around the edges is fishing line used to secure the cocoa basket to the metal frame. Sweetgum balls discourage cats from sleeping amid the flowers.

A tiny Rumex nestled in a basket lets me know when the Lantana need water. The clear filament around the edges is fishing line used to secure the cocoa basket to the metal frame. Sweetgum balls discourage cats from sleeping amid the flowers.

Vitex - A summer-blooming beauty

I receive a few phone calls every year from people who want me to identify “that tree with purple blooms, looks like a lilac.” That beauty, my friends, is Vitex agnus-castus, commonly called “Chaste tree.” Vitex can be described as a large deciduous shrub or a small tree. Cold-hardy from zone 7b to 11, Vitex tolerates any type of soil and is very drought tolerant once established. They will not survive boggy soils, so err on the side of less irrigation rather than more.

Vitex blooms smell sweet and their five-fingered leaves (resemble marijuana) have a pleasant sage-like fragrance too. The odor means that deer usually leave it alone.

Vitex forms a multi-stemmed tree but can be pruned to a single trunk if the gardener is so inclined. The lavender blooms appear at the ends of branches and point upward, making them look like a cousin to Clethra. Our region is becoming saturated with Crape Myrtles. I love the Crapes, but wish that more people would plant Vitex because of its benefit to pollinators. Butterflies and bees flock to the blooms. They are frequently planted near beehives to increase honey production. There is no fall color to mention, but the loose, rounded crowns have a special charm. They are quick growers, reaching a mature height of 25 feet. Plants thrive in heat, in full sun or part shade. I think they look best as an under story tree, in the partial shade cast by larger trees. A neighboring town used them in the central median plantings along a major highway, which confirms their hardy nature.

The Vitex in the Mary Snoddy garden is at least fifty years old, maybe more. It is starting to show the effects of old age, with a few branches dying here and there. When it reaches the end of its life, I plan to replace it with another specimen of the same type. ‘Shoal Creek’ has the typical lavender bloom, but ‘Alba’ is white and ‘Rosea’ has pink flowers. Several blue cultivars are available, and so are dwarf forms.

I was surprised to read that Vitex is considered invasive in certain areas of the Carolinas and several southwestern states. I have not seen that in my own garden, nor have I seen them proliferate in ungroomed areas.

If Vitex has a drawback, it is that the limbs tend to droop with age. While graceful, this creates difficulty in lawnmowing nearby. The thin bark is easily damaged by string trimmers. Surround them with a ground cover to eliminate the need to prune low-hanging limbs. A grass-like ground cover like Mondo Grass (Ophiopogon) tolerates shade cast by the tree and has the added advantage of absorbing the fine leaves shed in fall. No raking – Yay!

Bumblebees buzzing around the blooms of  Vitex angus-caste.

Bumblebees buzzing around the blooms of Vitex angus-caste.

A mature Vitex.

A mature Vitex.

Architectural Acanthus

One of my favorite plants for shade is Acanthus, (pronounced ah-KAN-thus) commonly called “Bear’s Breeches” for unknown reasons.  There are two species available in nurseries, Acanthus mollis and Acanthus spinosus. See the accompanying photograph for a side-by-side comparison.

Both species have bold evergreen leaves that draw attention in the garden. When you see one in bloom, you cannot help but say, “Golly!” The leaves of mollis are large and shiny; the leaves of spinosus bristle with sharp spines. (Bet you saw that one coming, huh?).  Leaf clumps may reach three feet tall. Bloom stems jump up to five feet or more. In the Mary Snoddy garden, the height of the bloom stem is a direct reflection of any irrigation I have thrown their way. The more water, the taller the stem. They do prefer a drier soil, however, so don’t get carried away with the watering. Ensure good drainage during winter to prevent root rot.

Acanthus’s distinctive leaves served as the pattern for carvings on classical Greek architecture. Blooms appear in early to mid summer on sturdy stems, white petals held by dusky purple bracts.

Acanthus are cold-hardy zone 7-10. They are evergreen in my zone 7b garden. Plants may spread by seed or by underground roots. I have seen reports of invasiveness on the internet, but have not experienced any such behavior in the ten-plus years I have enjoyed them. Deer, rabbits and voles avoid them.

Acanthus spinosus  on left;  Acanthus mollis  on right.

Acanthus spinosus on left; Acanthus mollis on right.

Prickly  Acanthus spinosus

Prickly Acanthus spinosus

Mary Snoddy and  Acanthus mollis  ‘Rue Ledan’

Mary Snoddy and Acanthus mollis ‘Rue Ledan’

Moonstruck Over Lunaria

Money does not grow on trees, but it does grow on Lunaria, whose common names include Money Plant, Dollar Plant, or Honesty. Lunaria annua would lead one to believe it is an annual, but it a biennial. The Lunaria portion means “moon like” in reference to its round white seeds, called silicles. As a true biennial, plants germinate and grow foliage one year, then flower, set seed, and die the next year. Blooms are purple, with an occasional lavender or white. They look spectacular paired with late season daffodils or bearded Iris. Average mature height is about two feet, with a spread half their height. Stems and leaves are both fuzzy to touch.

Seeds left on the plant are decorative through the summer but begin to look a bit tattered toward autumn. They self-sow, so allow a few seeds to remain to produce next year’s plants. Remove most seeds or you will be forced to remove an over-abundance of baby plants the following year. Retain and store a few seeds in a cool, dry place so you can plant them the following year. Otherwise, the biennial growth pattern will mean flowers only on alternate years. Seed pods, the “money,” are perfectly round, papery, almost translucent.  They look like two pieces of tissue paper with a couple of seeds caught between them. Seeds can be extracted by running the dry pod between your fingers. Children can help harvest and plant these. Stalks of mature seeds make interesting additions to flower arrangements.

Plants prefer the dappled shade of woodland gardens or under deciduous trees. In the Mary Snoddy garden, they thrive on neglect. I have never watered or fertilized them.

Don’t confuse Lunaria with Dame’s Rocket, an invasive plant with similar flowers but different seed pods.  

It is too bad that gardeners cannot use the Lunaria’s money to feed our voracious plant-buying habits.