A pretty little weed

Oxalis debilis is an attractive weed with pretty pink flowers, shamrock-shaped leaves and a compact mounded form

Simply Living
December 10, 2012

There are certain non-native plants (aka escaped exotics/weeds) that I’m rather fond of despite their purported invasiveness.  Among them, pink sorrel (Oxalis debilis) stands out, literally as well as figuratively. 

Without any assist from us, this low-growing, no-fuss perennial appears in our flowerbeds.  All year round – except during winter freezes - clusters of pretty, pink flowers top the green, shamrock-shaped leaves.

Little pink flowers bloom practically year-round

 

Although the plant spreads through underground rhizomes, I haven’t found pink sorrel to be particularly invasive.  That’s probably because it seems to have a decided preference for the enriched soil of garden beds and container plants.  I’ve walked all over our property but have never seen pink sorrel growing anywhere except areas where the soil has previously been augmented.  In such settings however, especially if they are sunny, I usually find multiple mounds of unplanted beauty.

Oxalis debilis is one of 900 members of Oxilidaceae, the wood sorrel family.  Although native to South America, wood sorrel plants exist in all but the coldest locations around the world.  There are some 30 varieties in the United States with six in Florida. 

All wood sorrels are edible, but they do contain oxalic acid, a chemical compound present in spinach, kale, beets, parsley and a number of other foods.  If eaten to excess, oxalic acid is toxic and can lead to kidney problems but it would be highly unlikely for that to happen with pink sorrel.  The leaves of this perennial plant are small and have a sour lemony flavor.  A few added to a salad might result in an interesting flavor but eating an entire bowlful would provide more tartness than most people would find palatable.

While I appreciate pink sorrel’s edible quality, that’s not the reason I’m so fond of the plant.  I like this self-propagating wildflower because it’s so pretty.  The green foliage forms rounded mounds that can reach up to eight inches tall with a foot-wide diameter and the small five-petal flowers that grow in clusters atop thin stems look like small pink stars.  In the evening and during periods of drought, the blooms close up.  The leaves do too.  When closed, the shamrock-shaped leaves look like tiny versions of those fortuneteller games I used to make out of folded paper when I was a kid.

Although pink sorrel grows wild in temperate garden beds, I like the plant best as a container plant in individual pots or mixed groupings.  I keep a couple containers of sorrel on the porch-side patio but people who live in colder climates often grow it indoors solely as a houseplant.  That’s what my daughter does.  Whenever I visit Jenny in her Massachusetts home, I admire the lush mound of Oxalis triangularis that sits on a table by a window in her living room.  Triangularis is a purple-leafed relative to Oxalis debilis that also produces pink blooms.

Oxalis triangularis has large purple leaves and pink-white flowers.  In this picture, it is growing in a container alongside a variegated spider plant

The Florida Exotic Pest Plant Council (www.fleppc.org) does not include pink sorrel as either a Category I or a Category II invasive plant but because it is a non-native plant with the ability to aggressively self-propagate, native plant advocates don’t encourage its use in the landscape.  The Florida Native Plant Society (www.fnps.org) lists only one variety of wood sorrel, Oxalis comiculate (better known as common yellow wood sorrel) as a Florida native.  However, from my experience, I’ve found the native oxalis tends to pop up in lawns, sidewalk cracks and between steppingstones.  Common yellow wood sorrel is also less showy and more difficult to eradicate than non-native pink sorrel.

Oxalis comiculate is a native plant with tiny yellow flowers and small leaves.  

Deciding what plants to incorporate into your landscape and which ones to discourage can be confusing, especially if one of your objectives is to work in harmony with the environment.  For me, the decision often comes down to which plants offer the most advantages to the home gardener for the least amount of time, effort and resources.  Pink sorrel fulfills those guidelines by being a disease-and-pest-resistant, drought-tolerant plant that doesn’t require irrigation or toxic sprays in order to thrive.  Its small flowers bloom practically year-round and it has lovely foliage to boot.  Even better, I don’t even have to plant it because this low-growing wildflower plants itself! 

Pink sorrel is an escaped exotic but that doesn’t make it a bad plant.  It’s a weed, albeit a pretty one, and while I’m not about to fill my garden with it, a few judiciously selected plants can add a bit of landscape beauty with minimal work.