From Cut Flower to Noxious Weed – The Story of Baby’s Breath

One of the most ubiquitous plants in cut flower arrangements hails from the steppes of Turkey and neighboring countries in Europe and Asia. It’s a perennial plant with a deep taproot and a globe-shaped, multi-branched inflorescence loaded with tiny white flowers. In full bloom it looks like a small cloud hovering above the ground. It’s airy appearance earns it the common name baby’s breath, and the attractive and durable nature of its flowers and flower stalks, both fresh and dried, have made it a staple in the floral industry. Sadly, additional traits have led to it becoming a troublesome weed outside of its native range.

baby’s breath (Gypsophila paniculata) via wikimedia commons

Gypsophila paniculata is in the family Caryophyllaceae – sharing this distinction with other cut flowers like carnations and pinks, as well as other weeds like chickweed and soapwort. At maturity and in full bloom, baby’s breath might reach three to four feet tall; however, its thick taproot extends deep into the ground as much as four times its height. Its leaves are unremarkable and sparse, found mostly towards the base of the plant and sometimes with a blue or purplish hue. The flowers are numerous and small, have a sweet scent to them (though not appreciated by everyone), and are pure white (sometimes light purple or pink).

Each flower produces just a few seeds that are black, kidney-shaped, and minuscule. Many of them drop from their fruits and land near their parent plant, but some are retained within their little capsules as the flower stalk dries and becomes brittle. Eventually a stiff breeze knocks the entire inflorescence loose and sends it tumbling across the ground. Its rounded shape makes it an effective tumbleweed, as the remaining seeds are shaken free and scattered far and wide.

baby’s breath flowers close up (via wikimedia commons)

Being a tumbleweed gives it an advantage when it comes to dispersing itself and establishing in new locations, but this is not the only trait that makes baby’s breath a successful weed. Its substantial taproot, tolerance to drought and a variety of soil conditions, and proclivity to grow along roadsides, in ditches, and abandoned fields also make it a formidable opponent. Mowing the plant down does little to stop it, as it grows right back from the crown. Best bets for control are repeated chemical treatments or digging out the top portion of the taproots. Luckily its seeds are fairly short-lived in the soil, so vigilant removal of seedlings and not allowing the plant to reproduce can help keep it in check. Baby’s breath doesn’t persist in regularly disturbed soil, so it’s generally not a problem in locations that are often cultivated like agricultural fields and gardens.

The first introductions of baby’s breath to North America occurred in the 1800’s. It was planted as an ornamental, but it wasn’t long before reports of its weedy nature were being made. One source lists Manitoba in 1887 as the location and year of the first report. It is now found growing wild across North America and is featured in the noxious weed lists in a few states, including Washington and California. It has been a particular problem on sand dunes in northwest Michigan, where it has been so successful in establishing itself that surveys have reported that 80% of all vegetation in certain areas is composed of baby’s breath.

baby’s breath in the wild (via wikimedia commons)

Invading sand dune habitats is particularly problematic because extensive stands of such a deep-rooted plant can over-stabilize the soil in an ecosystem adapted to regular wind disturbance. Plants native to the sand dunes can be negatively affected by the lack of soil movement. One species of particular concern is Pitcher’s thistle (Cirsium pitcheri), a federally threatened plant native to sand dunes along the upper Great Lakes. Much of the research on the invasive nature of baby’s breath and its removal comes from research being done in this region.

Among numerous concerns that invasive plants raise are the affects they can have on pollinator activity. Will introduced plants draw pollinators away from native plants or in some other way limit their reproductive success? Or might they help increase the number of pollinators in the area, which in turn could benefit native plants (something known as the magnet species effect)? The flowers of baby’s breath rarely self-pollinate; they require insect visitors to help move their pollen and are highly attractive to pollinating insects. A study published in the International Journal of Plant Sciences found that sand dune sites invaded by baby’s breath attracted significantly more pollinators compared to uninvaded sites, yet this did not result in more pollinator visits to Pitcher’s thistle. According to the researchers, “a reduction in pollinator visitation does not directly translate to a reduction in reproductive success,” but the findings are still a concern when it comes to the future of this threatened thistle.

Perhaps it’s no surprise that a plant commonly found in flower arrangements is also an invasive species, as so many of the plants we’ve grown for our own pleasure or use have gone on to cause problems in areas where they’ve been introduced. However, could the demand for this flower actually be a new business opportunity? Noxious weed flower bouquets anyone?

Related Posts:

Eating Weeds: Chicory

Over the course of human history, plant species once esteemed or considered useful have been recategorized into something less desirable. For one reason or another, plants fall out of favor or wear out their welcome, and, in come cases, are found to be downright obnoxious, ultimately losing their place in our yards and gardens. The particularly troublesome ones are branded as weeds, and put on our “do not plant” lists. These plants are not only unfavored, they’re despised. But being distinguished as a weed doesn’t necessary negate a plant’s usefulness. It’s likely that the plant still has some redeeming characteristics. We’ve just chosen instead to pay more attention its less redeeming ones.

Chicory is a good example of a plant like this. At one point in time, Cichorium intybus had a more prominent place in our gardens, right alongside dandelions in fact. European colonizers first introduced chicory to North America in the late 1700’s. Its leaves were harvested for use as a salad green and its roots were used to make a coffee additive or substitute. Before that, cultivation of chicory for these and other purposes had been going on across Europe for thousands of years, and it still goes on today to a certain extent. Along with other chicory varieties, a red-leafed form known as radicchio and a close cousin known as endive (Chicorium endivia) are grown as specialty crops, occassionally finding their way into our fanciest of salads.

Radicchio di Chioggia (Cichorium intybus var. foliosum) is a cultivated variety of chicory. (via wikimedia commons)

Chicory’s tough, adaptable nature and proclivity to escape cultivation have helped it become widespread, making itself at home in natural areas as well as urban and rural settings. Its perennial life history helps make it a fixture in the landscape. It sends down a long, sturdy taproot and settles in for the long haul. It tolerates dry, compacted soils with poor fertility and doesn’t shy away from roadside soils frequently scoured with salts. It’s as though it was designed to be a city weed.

Unlike many other perennial weeds, chicory doesn’t spread vegetatively. It starts its life as a seed, blown in from a nearby plant. After sprouting, it forms a dandelion-esque rosette of leaves during its first year. Wiry, branched stems rise up from the rosette in following years, reaching heights of anywhere from about a foot to 5 or 6 feet. When broken, leaves, stems, and roots ooze a milky sap. Abundant flowers form along the gangly stems. Like other plants in the aster family, each flower head is composed of multiple flowers. Chicory flower heads are all ray flowers, lacking the disc flowers found in the center of other plants in this family. The petals are a brilliant blue – sometimes pink or white. Individual flowers last less than a day and are largely pollinated by bees. The fruits lack the large pappus found on dandelions and other close relatives, but the seeds are still dispersed readily with the help of wind, animals, and human activity.

chicory (Cichorium intybus) via wikimedia commons

The most commonly consumed portions of chicory are its leaves and roots. Its flowers and flower buds are also edible. Young leaves and blanched leaves are favored because they are the least bitter. Excluding the leaves from light by burying or covering them up keeps them pale and reduces their bitter flavor. This is standard practice in the commercial production of certain chicory varieties. The taproots of chicory are dried, roasted, and ground for use as a coffee substitute. They are also harvested commercially for use as a natural sweetener due to their high concentration of inulin.

my puny chicory root

I harvested a single puny chicory root in order to make tea. On my bike ride to work there is a small, sad patch of chicory growing in the shade of large trees along the bike path. I was only able to pull one plant up by the roots. The others snapped off at the base. So, I took my tiny root, dried and roasted it in the oven, and ground it up in a coffee grinder. I followed instructions for roasting found on this website, but there are many other sources out there. I had just enough to make one small cup of tea, which reminded me of dandelion root teas I have had. Sierra found it to be very bitter, and I agreed but still enjoyed it. I figure that wild plants, especially those growing in stressful conditions like mine was, are likely to be more bitter and strong tasting compared to coddled, cultivated ones found in a garden.

roasted chicory root

roasted and ground chicory root

When I find a larger patch of feral chicory, I hope to try one of several recipes included in Luigi Ballerini’s book, A Feast of Weeds, as well as other recipes out there. I’ll be sure to let you know how it goes.

Are you curious to know how chicory became such a successful weed in North America? Check out this report in Ecology and Evolution to learn about the genetic explanation behind chicory’s success.

Idaho’s Native Milkweeds (Updated)

As David Epstein said in an interview on Longform Podcast, “Any time you write about science, somethings is going to be wrong; the problem is you don’t know what it is yet, so you better be ready to update your beliefs as you learn more.” Thanks to the newly published Guide to the Native Milkweeds of Idaho by Cecilia Lynn Kinter, lead botanist for Idaho Department of Fish and Game, I’ve been made aware of some things I got wrong in the first version of this post. I appreciate being corrected though, because I want to get things right. What follows is an updated version of the original post. The most substantial change is that there are actually five milkweed species native to Idaho rather than six. Be sure to check out Kinter’s free guide to learn more about this remarkable group of plants.

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Concern for monarch butterflies has resulted in increased interest in milkweeds. Understandably so, as they are the host plants and food source for the larval stage of these migrating butterflies. But milkweeds are an impressive group of plants in their own right, and their ecological role extends far beyond a single charismatic insect. Work to save the monarch butterfly, which requires halting milkweed losses and restoring milkweed populations, will in turn provide habitat for countless other organisms. A patch of milkweed teems with life, and our pursuits to protect a single caterpillar invite us to explore that.

Asclepias – also known as the milkweeds – is a genus consisting of around 140 species, 72 of which are native to the United States and Canada. Alaska and Hawaii are the only states in the U.S. that don’t have a native species of milkweed. The ranges of some species native to the United States extend down into Mexico where there are numerous other milkweed species. Central America and South America are also home to many distinct milkweed species. Asclepias species found in southern Africa are considered by many to actually belong in the genus Gomphocarpus.

The habitats milkweeds occupy are about as diverse as the genus itself – from wetlands to prairies, from deserts to forests, and practically anywhere in between. Some species occupy disturbed and/or neglected sites like roadsides, agricultural fields, and vacant lots. For this reason they are frequently viewed as a weed; however, such populations are easily managed, and with such an important ecological role to play, they don’t deserve to be vilified in this way.

Milkweed species are not distributed across the United States evenly. Texas and Arizona are home to the highest diversity with 37 and 29 species respectively. Idaho, my home state, is on the low end with five native species. The most abundant species found in Idaho is Asclepias speciosa, commonly known as showy milkweed.

showy milkweed (Asclepias speciosa)

Showy milkweed is distributed from central U.S. westward and can be found in all western states. It occurs throughout Idaho and is easily the best place to look for monarch caterpillars. In fact, the monarch butterfly is Idaho’s state insect, thanks in part to the abundance of showy milkweed, which is frequently found growing in large colonies due to its ability to reproduce vegetatively via adventitious shoots produced on lateral roots or underground stems. Only a handful of milkweed species reproduce this way. Showy milkweed reaches up to five feet tall and has large ovate, gray-green leaves. Like all milkweed species except one (Asclepias tuberosa), its stems and leaves contain milky, latex sap. In early summer, the stems are topped with large umbrella-shaped inflorescences composed of pale pink to pink-purple flowers.

The flowers of milkweed deserve a close examination. Right away you will notice unique features not seen on most other flowers. The petals of milkweed flowers bend backwards, which would otherwise allow easy access to the flower’s sex parts if it wasn’t for a series of hoods and horns protecting them. Collectively, these hoods and horns are called the corona, which houses glands that produce abundant nectar and has a series of slits where the anthers are exposed. The pollen grains of milkweed are contained in waxy sacs called pollinia. Two pollinia are connected together by a corpusculum giving this structure a wishbone appearance. An insect visiting the flower for nectar slips its leg into the slit, and the pollen sacs become attached with the help of the corpusculum. When the insect leaves, the pollen sacs follow. Pollination is successful when the pollen sacs are inadvertently deposited on the stigmas of another flower.

Milkweed flowers are not self-fertile, so they require assistance by insects to sexually reproduce. They are not picky about who does it either, and their profuse nectar draws in all kinds of insects including bees, butterflies, moths, beetles, wasps, and ants. Certain insects – like bumble bees and other large bees – are more efficient pollinators than others. Once pollinated, seeds are formed inside a pod-like fruit called a follicle. The follicles of showy milkweed can be around 5 inches long and house dozens to hundreds of seeds. When the follicle matures, it splits open to release the seeds, which are small, brown, papery disks with a tuft of soft, white, silky hair attached. The seeds of showy milkweed go airborne in late summer.

follicles forming on showy milkweed (Asclepias speciosa)

Whorled or narrowleaf milkweed (Asclepias fascicularis) occurs across western and southern Idaho. Its distribution continues into neighboring states. It is adapted to dry locations, but can be found in a variety of habitats. Like showy milkweed, it spreads rhizomatously as well as by seed. It’s a whispy plant that reaches one to three feet tall and occasionally taller. It has long, narrow leaves and produces tight clusters of greenish-white to pink-purple flowers. Its seed pods are long and slender and its seeds are about 1/4 inch long.

flowers of narrowleaf milkweed (Asclepias fascicularis)

seeds escaping from the follicle of narrowleaf milkweed (Asclepias fascicularis)

Swamp or rose milkweed (Asclepias incarnata) is more common east of Idaho, but occurs occasionally in southwestern Idaho. As its common name suggests, it prefers moist soils and is found in wetlands, wet meadows, and along streambanks. It can spread rhizomatously, but generally doesn’t spread very far. It reaches up to four feet tall, has deep green, lance-shaped leaves, and produces attractive, fragrant, pink to mauve, dome-shaped flower heads at the tops of its stems. Its seed pods are narrow and around 3 inches long.

swamp milkweed (Asclepias incarnata)

Asclepias cryptoceras ssp. davisii, or Davis’s milkweed, is a low-growing, drought-adapted, diminutive species that occurs in southwestern Idaho. It has round or oval-shaped leaves and produces flowers on a short stalk. The flowers have white or cream-colored petals and pink-purple hoods. The range of Asclepias cryptoceras – commonly known as pallid milkweed or jewel milkweed – extends beyond Idaho’s borders into Oregon and Nevada, creeping north into Washington and south into California. Another subspecies – cryptoceras – can be found in Nevada, Utah, and their bordering states.

Davis’s milkweed (Asclepias cryptoceras ssp. davisii)

The final species is rare in Idaho, as Idaho sits at the top of its native range. Asclepias asperula ssp. asperula, or spider milkweed, has a single documented location in Franklin County (southeastern Idaho). Keep your eyes peeled though, because this plant may occur elsewhere, either in Franklin County or neighboring counties. It grows up to two feet tall with an upright or sprawling habit and produces clusters of white to green-yellow flowers with maroon highlights. Its common name comes from the crab spiders frequently found hunting in its flower heads.

A sixth species, horsetail milkweed (Asclepias subverticillata), has been falsely reported in Idaho. Collections previously labeled as A. subverticillata have been determined to actually be the similar looking A. fascicularis.

Using Weeds: Soapwort

Over the past year or so I have written about several edible weeds in an effort to highlight useful weeds. However, weeds don’t have to be edible to be useful. In fact, many weeds are most certainly not edible, but that doesn’t mean they are of no use to humans. Soapwort, for example, is poisonous, and while it does have a history of being used internally as medicine, ingesting it is not advised and should only be done under the direction of a doctor. A much less risky activity would be to make soap out of it.

soapwort (Saponaria officinalis)

Saponaria officinalis, commonly known as bouncing bet, hedge pink, fuller’s herb, scourwort, and soapweed or soapwort, is an herbaceous perennial native to Europe. It has been planted widely in flower beds and herb gardens outside of its native range, desired both for its beauty and utility. Capitalizing on our appreciation for it, soapwort has expanded beyond our garden borders and into natural areas, as well as vacant lots, roadsides, and other neglected spaces. Even in a garden setting it can be a bit of a bully, especially if ignored for a season or two.

The stems of soapwort grow to about two feet tall, are unbranched, and sometimes tinged with pink, purple, or red. The leaves are oblong and oppositely-arranged, and their bases form prominent collars around the stems. Showy clusters of flowers are found atop the stems throughout the summer. Like other flowers in the pink family (Caryophyllaceae), they are cigar-shaped at the base and opened wide at the end, showing off 5 distinct petals with notches at their tips. The petals of soapwort flowers bend backwards, with their sex parts protruding outwards. In his description of the flowers, John Eastman remarks in The Book of Field and Roadside that “the reflexed petals surrounding the sexual organs give the impression of flagrant thrust; this is a gaudy, unshy flower.”

collared stem of soapwort (Saponaria officinalis)

The fragrant flowers are pink to white in color. They open in the evening and remain open for a few short days. In an individual flower, pollen matures and is mostly shed before the stigma is ready to accept it. This helps reduce the chance of self-pollination. Cross pollination occurs with the assistance of moths who visit the flowers at night, as well as bees and other flower-visiting insects that come along during the daytime. Soapwort fruits are oval capsules containing as many as 500 kidney-shaped seeds. Seeds aren’t essential to the plants spread though, as much of its colonization occurs via vigorous rhizomes.

In fact, vegetative reproduction is the means by which soapwort forms such expansive, thick patches. It also helps that it’s poisonous. The saponins – its soap making compounds – that it produces in its roots, shoots, and leaves deter most insects and other animals from eating it. It has a reputation for poisoning horses, cows, and other livestock, and so is unwelcome in pastures and rangelands. Saponins are also poisonous to fish, so growing soapwort near fish ponds is not advised.

soapwort (Saponaria officinalis)

Soapwort occurs in a variety of soils including sandy, dry, and rocky sites and is surprisingly drough-tolerant, fine qualities to have when colonizing neglected sites. While most other organisms ignore soapwort, it has a friend in humans. Eastman sums this up well: “Soapwort’s most important associate – as is true of most plants we label weeds – is undoubtedly humankind, without whose helpful interventions the plant would surely be much rarer than it is.”

I made a soapy liquid out of soapwort by following a recipe that can be found on various blogs and websites by searching “saponaria soap recipe.” Basically it’s a cup of fresh leaves and stems along with a cup of dried leaves and stems added to a quart of distilled water brought to a boil. After simmering for 15 minutes and then allowing it to cool, strain the mixture through cheese cloth, and it’s ready to go.

This gentle but effective soap can be used for cleaning countertops and other surfaces, as well as dishes, fabrics, and skin. Several sources say it is particularly useful for cleaning delicate fabrics. Sierra and I both found it to have a cooked cabbage or spinach scent to it. This can be masked by adding a few drops of essential oil. Despite its odd aroma, both Sierra and I were impressed by its cleansing power and plan to use it more often.

dried leaves of soapwort

soapwort soap

Field Trip: Green Spring Gardens and Meadowlark Botanical Gardens

Last month, Sierra and I were in Washington D.C. for the American Public Gardens Association annual meeting. We didn’t get to visit nearly as many gardens as I would have liked. Time was limited, and rain spoiled things a bit. However, we did get a chance to take an all day field trip to a few gardens in nearby Virginia. A couple of the gardens we visited on that trip were Green Spring Gardens in Alexandria, VA and Meadowlark Botanical Gardens in Vienna, VA.

Both gardens are quite large – Green Spring is over 30 acres and Meadowlark covers over 90 acres – and there wasn’t time to get the full experience at either location. Thus, my photos are scant and obviously not fully representative of either place. Either way, we had a good time visiting both gardens.

Green Spring Gardens

The Fairfax County Parks Authority owns and operates Green Spring Gardens. Among other partnerships, they receive considerable support from a non-profit organization called Friends of Green Spring. Although it was the wrong time of year to see them in bloom, Green Spring Gardens has a nationally accredited witch hazel collection that I’m sure would be worth checking out in the winter months. I enjoyed walking through the native plant garden, seeing the newly planted crevice garden, and learning about magnolia bogs from a friendly and enthusiastic volunteer.

the pink form of smooth azalea (Rhododendron arborescens) in the Virginia Native Plant Garden

jewelweed (Impatiens capensis) in the Virginia Native Plant Garden

bush honeysuckle (Diervilla lonicera) in the Virginia Native Plant Garden

hornbeam inflorescence (Carpinus sp.)

newly planted crevice garden

rain lily (Zephyranthes sp.) in the crevice garden

Meadowlark Botanical Gardens

Meadowlark is owned and operated by NOVA Parks. Its immense size made it difficult to decide what to check out in the little time we had, but we were happy with our decision to stop by the wetlands (to see the knees on the Taxodium distichum) and walk through the forested nature trail. We also had fun watching all the bumblebees lumber about from flower to flower.

lichen on Yoshino cherry (Prunus x yedoensis)

bumblebee on common milkweed (Asclepias syriaca)

bumblebees climbing inside leatherflower blossoms (Clematis viorna)

scarlet beebalm (Monarda didyma)

A small peak into what was a very large Fairy Garden

blue leaf form of dusty zenobia (Zenobia pulverulenta)

bear’s breeches (Acanthus sp.)

Armenian cranesbill (Geranium psilostemon)

More Awkward Botany Field Trips:

Drought Tolerant Plants: Ice Plants

Among the various strategies plants have for tolerating drought, succulence is easily one of the most common and most successful. A recent article in the new open source journal, Plants People Planet, explores the world of succulent plants, commenting on, among other things, their evolution and extent. At least 83 plant families contain succulent species, and as many as 3-5% of flowering plants are considered succulents.

Succulence involves the storage of water in the cells of one or more plant organs (i.e. roots, stems, or leaves) as a mechanism for surviving drought. One way that succulent species differ is the location and nature of this storage. Some succulents are all cell succulents, meaning that the cells involved in storing water are also involved in carrying out photosynthesis. Other succulents are storage succulents. They have specific cells called hydrenchyma designed for storing water. These cells are non-photosynthetic.

Plants in the family Aizoaceae are storage succulents. Commonly known as the ice plant or carpet weed family, this family consists of hundreds of species and is mainly distributed throughout a region of South Africa known as Succulent Karoo. Species in this family earn the name ice plant thanks to numerous bladder-like cells or hairs that cover their leaves and stems causing them to sparkle or glimmer in the light. Aizoaceae diversity is incredible, and while this post focuses mainly on a few select species, it’s worth browsing through the profiles listed on World of Succulents to appreciate the breadth of forms these plants can take.

common ice plant (Mesembryanthemum crystallinum)

Among many interesting features that plants in this family possess, one particularly fun thing to note is that their flowers, which are unapologetically showy, lack true petals. Instead, what appear as a series of flat, thin petals encircling the center of the flower are actually modified stamens. They act as petals – drawing in pollinators with their bright colors – so calling them petals is acceptable, just not entirely accurate. Another fun fact is that seed pods of plants in Aizoaceae are often hygrochastic – upon getting wet they burst open and expel their seeds.

The photosynthetic pathway in succulents is generally different compared to other plants. Instead of the common C3 pathway, succulents use a pathway called CAM, or Crassulacean Acid Metabolism. CAM photosynthesis is similar to C4 photosynthesis – another photosynthetic pathway common among drought tolerant plants – in that it uses PEP carboxylase instead of rubisco to fix carbon and then sends it to a separate cell to be converted into sugars. In C4 photosynthesis, this whole process happens during the day. CAM photosynthesis differs in that it fixes carbon during the night and then sends it to another cell to be converted into sugars during the day. Fixing carbon at night is a way to avoid the water loss that occurs when collecting carbon dioxide during the daytime.

In discussing Aizoaceae, this is an important consideration because, unlike many other succulents, plants in this family don’t rely solely on CAM photosynthesis, but can instead switch back and forth between C3 and CAM. The ability to do this is likely because they are storage succulents rather than all cell succulents, and because they can do this, they are very efficient carbon fixers.

flowers fading on purple ice plant (Delosperma cooperi)

I live in a region where winter temperatures can dip into the single digits (°F) and sometimes lower,  so my familiarity with ice plants is with cold hardy species and cultivars of the genus Delosperma. If you are familiar with this group of plants, it is most likely thanks to the Plant Select program based in Colorado, particularly the work of Mr. Delosperma himself, Panayoti Kelaidis. Several Delosperma species are cold hardy in the Intermountain West. Thanks to their promiscuous nature, numerous crosses have occurred between species and varieties, resulting in a wide array of flower colors. And speaking of their flowers, the glistening leaves of Delosperma have nothing on their shimmering flowers, some of which may have the ability to temporarily blind you if you’re not careful. Sun is essential though, as they usually close up when shaded.

The cold hardy ice plants of the Delosperma genus are all groundcovers, maintaining a low and creeping profile. Some creep further than others. They are generally not fond of heavy clay soils, and instead prefer soil with good drainage. During the hot, dry days of summer, they appreciate a little water now and then, but watering should be cut off at the end of summer so that they aren’t sitting in saturated soils as winter approaches. They love the sun and will generally flower from late spring throughout the summer. Of course, thanks to their interesting foliage, they catch the eye and provide interest in the garden even when they aren’t flowering.

Fire Spinner® ice plant (Delosperma ‘P001S’)

Within Aizoaceae there are several species that go by the name ice plant that are not so cold hardy. Some are grown as house plants, while others are common in gardens. Still others, like Carpobrotus edulis, were once employed by land managers in California to help control erosion. However, like a number of species introduced for this purpose, C. edulis (commonly known as highway ice plant or hottentot fig) has made itself at home in areas where it wasn’t invited. It has become particularly problematic in coastal ecosystems, spreading quickly across sandy soils and outcompeting native plants. Despite being brought in to control erosion, it actually causes erosion in steep, sandy areas when its carpet-like growth becomes heavy with water and begins sliding down the hill.

highway ice plant (Carpbrotus edulis) carpeting a slope near San Diego – photo credit: Sierra Laverty

Introducing plants to our gardens that come to us from the other side of the globe should be done with caution and care. We don’t want to be responsible for the next invasive species. Since ice plant species have become problematic in California, should we be concerned about cold hardy delospermas? In trialing their plants, invasive qualities are among those that the Plant Select program watches out for, and delospermas seem pretty safe. However, as Kelaidis observes in a blog post from 2014, we should remain vigilant.

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Eating Weeds: Blue Mustard

Spring is here, and it’s time to start eating weeds again. One of the earliest edible weeds to emerge in the spring is Chorispora tenella, commonly known by many names including blue mustard, crossflower, and musk mustard. Introduced to North America from Russia and southwestern Asia, this annual mustard has become commonplace in disturbed areas, and is particularly fond of sunny, dry spots with poor soil. It can become problematic in agricultural areas, but to those who enjoy eating it, seeing it in large quantities isn’t necessarily viewed as a problem.

rosettes of blue mustard (Chorispora tenella)

The plant starts off as a rosette. Identifying it can be challenging because the shape of the leaves and leaf margins can be so variable. Leaves can either be lance-shaped with a rounded tip or more of an egg shape. Leaf margins are usually wavy and can be deeply lobed to mildly lobed or not lobed at all. Leaves are semi-succulent and usually covered sparsely in sticky hairs, a condition that botanists refer to as glandular.

A leafy flower stalk rises from the rosette and reaches between 6 and 18 inches tall. Like all plants in the mustard family, the flowers are four-petaled and cross-shaped. They are about a half inch across and pale purple to blue in color. Soon they turn into long, slender seed pods that break apart into several two-seeded sections. Splitting apart crosswise like a pill capsule rather than lengthwise is an unusual trait for a plant in the mustard family.

blue mustard (Chorispora tenella)

Multiple sources comment on the smell of the plant. Weeds of North America calls it “ill-scented.” Its Wikipedia entry refers to it as having “a strong scent which is generally considered unpleasant.” The blog Hunger and Thirst comments on its “wet dish rag” smell, and Southwest Colorado Wildflowers claims that its “peculiar odor” is akin to warm, melting crayons. Weeds of the West says it has a “disagreeable odor,” and warns of the funny tasting milk that results when cows eat it. All this to say that the plant is notorious for smelling bad; however, I have yet to detect the smell. My sense of smell isn’t my greatest strength, which probably explains why I’m not picking up the scent. It could also be because I haven’t encountered it growing in large enough quantities in a single location. Maybe I’m just not getting a strong enough whiff.

Regardless of its smell, for those of us inclined to eat weeds, the scent doesn’t seem to turn us away. The entire plant is edible, but the leaves are probably the part most commonly consumed. The leaves are thick and have a mushroom-like taste to them. They also have a radish or horseradish spiciness akin to arugula, a fellow member of the mustard family. I haven’t found them to be particularly spicy, but I think the spiciness depends on what stage the plant is in when the leaves are harvested. I have only eaten the leaves of very young plants.

The leaves are great in salads and sandwiches, and can also be sauteed, steamed, or fried. I borrowed Backyard Forager’s idea and tried them in finger sandwiches, because who can resist tiny sandwiches? I added cucumber to mine and thought they were delicious. If you’re new to eating weeds, blue mustard is a pretty safe bet to start with – a gateway weed, if you will.

blue mustard and cucumber finger sandwiches

For more information about blue mustard, go here.

Eating Weeds 2018: