Experience Oxalis!

an image of Oxalis stricta with yellow flower

By Ellen Barredo

(This article was first published in the March 2006 issue of The Gateway Gardener.)
an image of Oxalis stricta with yellow flower

Oxalis stricta, or wood sorrel, in bloom. Photo courtesy Ellen Barredo

My first experience with Oxalis occurred on the 25-minute walk to ele- mentary school. The sidewalk I traveled passed by many big, beautiful houses sur- rounded by gardens of all descriptions. Although these gardens were full of blooming flowers, the lawns were typically filled with the current weed of the season. May always produced the first crop of wild, edible wood sorrell or sour grass. It is formally referred to as Oxalis stricta as defined by Edgar Denison in “Missouri Wildflowers”. The petite yellow blooms are followed by little seed capsules….so tart and tangy. I ate a big handful almost every day when in season. Little did I know they are just full of vitamin C and potassium! Of course with the prevalent use of lawn chemicals now, this habit of eating weeds may not be safe, and as with many wild edibles, eating too many may not be good, either.

The oxalis or “good luck” plant is most commonly found for sale during the month of March at your local garden center. The three-lobed leaf is a symbol of good luck in Ireland and is proudly worn as a “good luck” badge on St. Patrick’s Day. The leaves also press dry nicely in between the pages of the phone book and are easily mailed to anyone needing a little luck!

Oxalis is a genus of plants with over 800 varieties, native to Chile and South Africa. The word is from the Greek “Oxis,” meaning sharp or sour, referring to the acidity in the leaves. They grow from small corms or tuberous roots which produce delicate, clover-like leaves that close at night. This habit is called nyctinastic. The process actually helps the plant conserve heat at night. The leaves range from a green to purple color with flowers that come in a variety of colors including white, cream, yellow, pink, purple and red.

Care for your oxalis by placing it in a sunny window facing east. They enjoy a temperature of 60 to 70 degrees and misting. Feed it weekly while actively growing and blooming with a water soluble fertilizer and a pinch of time-released fertilizer. When the plants stop blooming feed every other month. When watering make sure you are thorough and that the water drains freely from the bottom of the pot. Never allow the plant to sit in water. Water will not be required again till the plants soil is dry. Just wiggle your finger in to feel the soil, or lift the pot to check the weight. Sometimes, the plants will go dormant. They will look tired and limp. Just let the soil dry out in the pot for a couple of months and allow the bulbs to rest. Then return the plant to a sunny location, water, and it will come back to life.

Oxalis is an excellent candidate for pots outdoors in part shade. Euro American, a supplier of plants to growers, has released several new oxalis to offer for spring 2006. Possibly premiering at your local garden center are ‘Charmed Wine,’ ‘Charmed Jade,’ and ‘Charmed Velvet.’ If you desire more of the unusual, Telos Rare Bulbs offers over 75 types of oxalis. Reach them at www.telosrarebulbs.com for information and photos.

Ellen Barredo studied horticulture at the St. Louis Community College at Meramec, and is a Missouri Certified Nursery Professional with more than 27 years in professional horticulture. She works at Bowood Farms and can be reached at (314) 454-6868.