Oxalis, Good Luck Plant, Wood Sorrel 'Iron Cross'

Oxalis tetraphylla

Family: Oxalidaceae
Genus: Oxalis (oks-AL-iss) (Info)
Species: tetraphylla (tet-ruh-FIL-uh) (Info)
Cultivar: Iron Cross



Water Requirements:

Average Water Needs; Water regularly; do not overwater

Sun Exposure:

Sun to Partial Shade


Grown for foliage

Good Fall Color

Foliage Color:



6-12 in. (15-30 cm)


12-15 in. (30-38 cm)


USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

Where to Grow:

Unknown - Tell us


Unknown - Tell us

Bloom Color:


Bloom Characteristics:

Unknown - Tell us

Bloom Size:

Unknown - Tell us

Bloom Time:

Late Spring/Early Summer

Mid Summer

Late Summer/Early Fall

Other details:

Unknown - Tell us

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:

Unknown - Tell us

Propagation Methods:

By dividing rhizomes, tubers, corms or bulbs (including offsets)

Seed Collecting:

Unknown - Tell us


This plant is said to grow outdoors in the following regions:

Auburn, Alabama

Mc Calla, Alabama

Mesa, Arizona

Calistoga, California

Menlo Park, California

Oceanside, California

Reseda, California

San Francisco, California

San Leandro, California

Temecula, California


Colorado Springs, Colorado

Meriden, Connecticut

Keystone Heights, Florida

Pensacola, Florida

Stone Mountain, Georgia

Canton, Illinois

Columbus, Indiana

Indianapolis, Indiana

Inwood, Iowa

London, Kentucky

Mount Sterling, Kentucky

Deridder, Louisiana

Metairie, Louisiana

North Billerica, Massachusetts

Grand Rapids, Michigan

Owosso, Michigan

Maben, Mississippi

Mathiston, Mississippi

Perryville, Missouri

Albuquerque, New Mexico

La Luz, New Mexico

Elizabeth City, North Carolina

Greenville, North Carolina

Leicester, North Carolina

Murphy, North Carolina

Cincinnati, Ohio

Hamilton, Ohio

Painesville, Ohio

Tulsa, Oklahoma

Brookhaven, Pennsylvania

Royersford, Pennsylvania

Warren Center, Pennsylvania

Regina, Saskatchewan

Bluffton, South Carolina

Austin, Texas(2 reports)

Fort Worth, Texas

Houston, Texas

Richmond, Texas

Roanoke, Texas

San Antonio, Texas

Winnsboro, Texas

Magna, Utah

Cascade, Virginia

Verona, Virginia

Bellevue, Washington

Kalama, Washington

Lacey, Washington

Port Townsend, Washington(2 reports)

Spanaway, Washington

Vancouver, Washington

Hartland, Wisconsin

show all

Gardeners' Notes:


On Apr 18, 2020, Tom_adams246 from Melbourne,
Australia wrote:

Hello I have some orange dots under the leaves of this plant what is it? Thanks


On Mar 19, 2016, saskboy from Regina, SK (Zone 3b) wrote:

this a tough an resilient little powerhouse of a plant.It is a great filler for a mixed container planting. The dark blotches on the leaves combine well with other dark purple/black flowers. The flowers are sporadic but nice- small, mid-pink and held in loose, airy sprays.
I had a very successful container combining this plant with petunia "black velvet", impatiens "tempo violet", sweet potato vine "blackie", and verbena "Lanai bright pink".
It does well in about half sun. average water needs. multiplies like mad.


On Sep 26, 2014, docknee from Murphy, NC (Zone 7a) wrote:

A lovely addition to hanging pots with caladiums, tuberous begonia and other partial shade loving plants. I use to add color and variety to containers, hanging pots and woodland borders. Dainty pink blooms wave in the breeze all summer long. I am in 6a or b due to elevation so I lift and store for the winter.


On Aug 16, 2014, EdwinR from Stockholm,
Sweden wrote:

Oxalis is one of my favourite houseplants but I am not succeeding with any of them this year. I planted Iron Cross corms in the spring. 2 came up. One died. The surviving one has 2 crooked leaves, nothing else, It is now on my glazed balcony. I hope it will grow more, less crooked leaves and flower there.


On Mar 10, 2012, TM3 from Irving, TX wrote:

I got 6 iron cross bulbs in August as a gift and planted them 2 weeks ago indoors in a pot all their own near the glass sliding glass door so they can get sun. (New potting soil). I watered them at first, and have been watering them once a week. They have not sprouted. Any advice?

Thank you for your help.


On Jun 12, 2010, jacoy78 from Salt Lake City, UT (Zone 5a) wrote:

I LOVE this plant. I purchased a single plant about 6 weeks ago. It sits in a location where it gets mostly full sun/borderline part sun. I water it frequently, and it get's watered by accident when I spray down the walk way to my house. It doesn't seem to mind, it is flourishing. When I leave for work in the morning the stems and leaves are all perked up as if to say, "Hello, have a happy lucky day!" Every morning I approach my car with a huge smile on my face. I am definitely going to buy more. I've never had a plant that I enjoy more than this little guy. Periodically, I remove the older leaves. This seems to have added some benefit. This particular plant of mine keeps a nice rounded shape. I really can't say enough about how much I LOVE this plant. I want MORE!!!


On Jun 11, 2010, ms_greenjeans from Hopkins, MN (Zone 4a) wrote:

I planted 5 little bulbs/tubers/or whatever they are, and in one summer had enough for myself and 3 other people. When I dug them up in the fall to store for the winter, they were huge! I shared them with several friends this spring. I am going to experiment with leaving one or two in the ground over the winter (I'm in zone 4a). Whether they make it or not, I'll still have plenty. This is a very attractive plant and it's interesting that the flowers open in the morning and fold up by mid-afternoon or so. They bloom all summer long. Mine perform best in part shade and do need watering every couple of days if it doesn't rain.


On Aug 18, 2009, DracoVolans from Crestline, CA (Zone 8b) wrote:

I bought this plant a couple of years ago on a whim, one of my few "impulse buys". It's colour and four-leafed clover appearance were what caught my eye and it has been a favourite of mine ever since. It was difficult to keep in my dim old house. We didn't get much light in any of the windows, and winter can be especially dreary in Winnipeg.

Yet I was determined to grow this one, and so placed it in the sunniest window we had and hoped. It wilted, it drooped, I'd water it and it would perk up. Then within the next day or two, it would be flagging again. Seems it's a water-hungry thing, and the desert dry humidity in my house was sucking it of any moisture, but with careful attention, it thrived, even bloomed, and I was happy.

Later, I was beginning a lon... read more


On Jul 9, 2009, art_n_garden from Colorado Springs, CO (Zone 6a) wrote:

I was really weary that an Oxalis could really be hardy for me. I was sure I was right when I hadn't seen it through May or June...but sure enough it started to pop up in late June. I'm in Zone 6 - and I'm glad to have found this one!


On Feb 4, 2009, mjab17 from North Billerica, MA wrote:

i grew this when i was really only starting to get into gardening, i really liked them and was sad that when i kepted them in the ground over winter they never returned ... i know better now .. i was even more sad when i couldn't find them anywhere for a few years ..... now i've found them once again and although theres still snow on the ground ( and theres a lot of it ) they are potted up and there foilige is just as pretty as ever -- but i've yet to see them bloom, can't wait till they do. And can't wait to get them back out in the yard again -- but they are deffently coming back inside this year


On Aug 4, 2008, vossner from East Texas,
United States (Zone 8a) wrote:

I agree that this cultivar seems to prefer more sun than the shady spot I've given it. Mine is in a pot in the shade and it is kinda leggy, searching for sunlight.


On Jul 6, 2008, Gigglesann from Lacey, WA (Zone 7b) wrote:

Iron Cross is easily my favorite plant in the front of my garden with it's interesting leaves and dainty salmon pink flowers. It does fine in full sun. The leaves and flowers close up at night and open with the sun. These plants were here when we moved in two years ago. They disappear in the fall and reappear in the spring.


On May 12, 2008, dalmatian_fan87 from Cascade, VA (Zone 7a) wrote:

a WONDERFUL oxalis species...the first time i tried it, it bloomed before any of the leaves even opened! but the leaves werent far behind! such a lovely color combo on the leaves!


On Feb 18, 2008, Malus2006 from Coon Rapids, MN (Zone 4a) wrote:

I grow them into pots - they thrive in shade so make good accesoories with other shade annuals and then you can storage the bulbs inside for the winter.


On Sep 28, 2007, Astramorgaine from Columbus, IN (Zone 5b) wrote:

I live in zone 5b, and the iron cross oxalis makes a fabulous addition to my garden! I received the bulbs as a gift in July (clearance bulbs) and decided to just plant them then. I'm glad I didn't wait, for now they are sprouting and blooming!


On Jul 18, 2006, ademink from Indianapolis, IN wrote:

I'm in Indianapolis in Zone 5 and I'm on my 3rd year of this plant coming back for me! It's planted about 2-3' from the house, southern exposure. I thought I had lifted all of the bulbs the first Fall but the next Spring realized I hadn't. Now I just leave them and they have spread like crazy and are doing beautifully. Looks like the zone can go further than thought! :)


On Jun 9, 2006, MotherNature4 from Bartow, FL (Zone 9a) wrote:

I don't have any experience growing this cultivar, but look forward to it. The center of the leaves is marked with purple, thus the name Iron Cross.
They prefer a fairly sunny location.


On Nov 2, 2005, Sarahskeeper from Brockton, MA (Zone 6a) wrote:

I really like this one. Super easy to grow in almost any location.
It multiplies fast, I initially got 5 bulbs as a promotional mail order gift. Within a few years I had enough to give extras away.
They are 'tender' bulbs, so treat them like Dahlias, lift them in the fall and store them in a cool not freezing location in a paper bag.
Divide in spring and plant after danger of frost has past.
It can bloom in as little as 2 weeks after planting, in warm conditions.
Nice in pots or as ground cover.
Andy P


On May 30, 2005, mkjones from Aurora, TX (Zone 8a) wrote:

A delightfully different oxalis--and fast growing! I planted bulbs just two weeks ago, and already have two little beds going. The blooms are such a beautiful coral pink, with a spiralling effect in opening, leaving the blossom fan-like. I really like this plant.


On Aug 22, 2004, kooger from Oostburg, WI (Zone 5b) wrote:

I planted 20 bulbs in a pot. These bulbs were ones I had forgotten about and were all dried up. I thought maybe a few would grow but it looks like they all did. I really enjoy them but next year will spread them out over a few pots. They need twice daily watering to not droop.


On Dec 6, 2002, dubhloaich from Scappoose, OR wrote:

This is a wonderful companion plant to Geranium phaeum 'Samobar', with each enhancing the variegation of the other. Both of look wonderful under Cercis Canadensis 'Forest Pansy'.

It has been slow to emerge in the spring, so don't assume it was lost over the winter. It should be putting up leaves by mid-May.

It should be noted that all Oxalis foliage contains oxalic acid, which puts the sour in sourgrass. Although chewing on a leaf or two is harmless, it is possible to ingest enough leaves to get a toxic dose of oxalic acid.