Thyrsacanthus Species, Cardinal Guard, Firespike, Scarlet Flame

Thyrsacanthus tubaeformis

Family: Acanthaceae (ah-kanth-AY-see-ee) (Info)
Genus: Thyrsacanthus
Species: tubaeformis
Synonym:Justicia tubaeformis
Synonym:Odontonema longifolium
Synonym:Odontonema strictum
Synonym:Odontonema tubaeforme
Synonym:Thyrsacanthus strictus
View this plant in a garden


Tropicals and Tender Perennials

Water Requirements:

Average Water Needs; Water regularly; do not overwater

Sun Exposure:

Sun to Partial Shade




Foliage Color:



36-48 in. (90-120 cm)


24-36 in. (60-90 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)

USDA Zone 11: above 4.5 C (40 F)

Where to Grow:

Grow outdoors year-round in hardiness zone



Bloom Color:


Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Bloom Size:

Unknown - Tell us

Bloom Time:

Late Winter/Early Spring

Late Summer/Early Fall

Mid Fall

Late Fall/Early Winter

Mid Winter

Other details:

Unknown - Tell us

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

Patent Information:


Propagation Methods:

From softwood cuttings

From seed; direct sow after last frost

Seed Collecting:

Allow seedheads to dry on plants; remove and collect seeds


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

Mobile, Alabama

Waverly, Alabama

Carlsbad, California

Lakewood, California

San Diego, California

San Marino, California

Vista, California(9 reports)

Bartow, Florida

Big Pine Key, Florida

Boca Raton, Florida(3 reports)

Bokeelia, Florida

Bonita Springs, Florida

Brooksville, Florida(2 reports)

Chiefland, Florida

Daytona Beach, Florida

Deland, Florida

Dunnellon, Florida

Fernandina Beach, Florida

Floral City, Florida

Fort Lauderdale, Florida(3 reports)

Fort Pierce, Florida

Gainesville, Florida

Hobe Sound, Florida

Hollywood, Florida

Hudson, Florida

Inverness, Florida

Jacksonville, Florida(6 reports)

Key West, Florida

Keystone Heights, Florida

Lakeland, Florida

Largo, Florida

Longwood, Florida

Lynn Haven, Florida

Melbourne, Florida(2 reports)

Miami, Florida(2 reports)

Miccosukee Cpo, Florida

Naples, Florida

Navarre, Florida

Neptune Beach, Florida

Niceville, Florida

Orange Park, Florida

Orlando, Florida(3 reports)

Panama City, Florida

Pensacola, Florida

Pompano Beach, Florida(2 reports)

Punta Gorda, Florida

Ruskin, Florida

Safety Harbor, Florida

Saint Augustine, Florida

Saint Petersburg, Florida

Sanford, Florida

Sarasota, Florida(3 reports)

Sebastian, Florida

Sebring, Florida

Sorrento, Florida

Spring Hill, Florida

Tallahassee, Florida

Trenton, Florida

Vero Beach, Florida

West Palm Beach, Florida(3 reports)

Winter Springs, Florida

Zephyrhills, Florida

Ashburn, Georgia

Moultrie, Georgia

Savannah, Georgia

Kurtistown, Hawaii

Baton Rouge, Louisiana(3 reports)

Bossier City, Louisiana

Franklinton, Louisiana

Independence, Louisiana

Lafayette, Louisiana

Mandeville, Louisiana(2 reports)

New Orleans, Louisiana

Prairieville, Louisiana

Slaughter, Louisiana

Gautier, Mississippi

Mathiston, Mississippi

Saucier, Mississippi

Elizabeth City, North Carolina

Monroe, North Carolina

Beaufort, South Carolina(2 reports)

Camden, South Carolina

Conway, South Carolina

Johns Island, South Carolina

Moncks Corner, South Carolina

Sumter, South Carolina

Adkins, Texas

Alice, Texas

Arlington, Texas

Austin, Texas(6 reports)

Belton, Texas

Colmesneil, Texas

Dallas, Texas(2 reports)

Desoto, Texas

Dickinson, Texas

Edinburg, Texas

Fate, Texas

Flatonia, Texas

Fort Worth, Texas

Garland, Texas

Houston, Texas(5 reports)

Huntsville, Texas

Jacksonville, Texas

La Vernia, Texas

Lake Jackson, Texas

Mc Kinney, Texas

Mission, Texas

New Waverly, Texas

Oakhurst, Texas

Pflugerville, Texas

Red Oak, Texas

Richmond, Texas

San Antonio, Texas(3 reports)

Santa Fe, Texas

Shepherd, Texas

Spring, Texas

Zapata, Texas

Virginia Beach, Virginia

show all

Gardeners' Notes:


On Mar 21, 2017, coriaceous from ROSLINDALE, MA wrote:

Here in Ajijic, Jalisco, Mexico (USDA Z11), it forms a narrowly upright, sparsely branched evergreen shrub to 8' tall. Bloom was finished by the time I arrived at Christmas.

Forms a tight clump that does not spread quickly. Makes a useful hedge. Holds glossy evergreen foliage all the way to the ground.

Here the leaves sometimes have yellow markings that look like a variegation (and some not, even on the same plant). I wonder if this is due to a disease or a nutritional deficiency.

Performs well in full shade. Doing well here in very heavy soil that's often saturated in summer and dry in winter.

The botanical name is now Odontonema strictum.


On Mar 21, 2017, lightyellow from Ponte Vedra Beach, FL wrote:

Here is my experience/a review of the plant based on a site in zone 9a/b in Northeastern Florida:

Firespike is basically a late autumn to early spring (with most flowers around December) flowering perennial that is like a combination of a hosta and a red saliva. It is one of my favorite plants in my yard.

Soil- Best grown in whatever soil stays somewhat moist yet-well-drained, doesn't get too hot and has at least some natural organic matter to it like fallen leaves or substitutes like manure.

Light- Lighting should be soft, dappled shade (mine receives shade from a long-leaved palm tree+off-property oak behing it and a large crepe myrtle that belongs to a neighbor to the front+side of it) ideally with some early morning or late evening sun but ... read more


On Dec 8, 2013, vossner from East Texas,
United States (Zone 8a) wrote:

It's been a while, but a lovely DGer gave me seeds that looked like walnuts and told me to plant directly inground, which I did in a moist and shady section of my garden. It dies to the ground but each year it gets bigger and showier. With respect to the seeds, I hope I am not confusing this with another plant but I'm pretty sure seeds were big.


On Dec 8, 2013, bmpswel from Tampa, FL wrote:

I read other readers comments wondering if anyone is having the same problem I have. I wanted to see if anyone has suggestions to help me correct my firespikes. I planted 2 firespikes in my front yard and 2 in the backyard. I'm having the same, strange problem in both locations. One of the plants in the front yard and one in the back have very pale green leaves and grow really slow. I've corrected my Ph this summer, but it hasn't affected the firespikes.


On Dec 1, 2012, brandy54 from Houston, TX wrote:

Receivedu aa cutting about 3 years ago did not know what it was, made it through Houston heat , first years it has bloomed , growing in a clay pot. After the bloom was able to find the name .


On Oct 2, 2012, tlm1 from Jacksonville, FL (Zone 9a) wrote:

Love this plant, as do the Hummingbirds. I question the size though that is listed in this file. Currently my bush is nearly 6' tall, and just as wide. Quite a bit larger than this file states. Give it plenty of room!


On Feb 12, 2012, morningloree from Heathrow, FL wrote:

Perfect for planting around the base of an oak tree, it gets some morning sun, but mostly shade. Thought we would be frost proof by now, but it got down to 33 degrees and no sign of damage. I had some soft wood cuttings that I had just put in a pot, again, no problem. This plant is truly semi-tropical. Great for partially shaded areas, still blooming in February, although is primarily supposed to bloom in Winter and Fall.


On Dec 10, 2010, ThomPotempa from Houston, TX wrote:

This stuff is impossible to kill.

I bought some for the first time this spring. They are sitting in a bed I don't water.

I had to dig them up about a month after planting since I had to remove the tree that they were around.

Then about 6 months later, in the heat of August, the local utility had to dig where they were. They through the plants to the side.

I gave them water soaking for about 1 hour after replanting. After that no more water.

In the drought.

They are blooming beautifully as I type this...


On Oct 24, 2010, Kiyzersoze from Coral Springs, FL (Zone 10b) wrote:

It took several years for this plant to become happy in it's location but it was worth the wait. Nice plant that blooms a long time and is really pretty once it gets established.


On Nov 19, 2009, singleshotcajun from Dickinson, TX wrote:

When I moved to Texas a Friend allowed me to dig plants in her overgrown rent house yard . This is one I dug up and transplanted to my yard.It is the most trouble free pant I have ever experienced. Propagates without care or much prep. In my yard which is mostly shade this is one of the precious few pants that make red my wife likes red and if not for Geraniums and Firespike She would have none so I am a hero thanks to this plant. No need for root stimulator just cut it and stick it in the dirt. Thanks to members on this forum for identifying it for me.


On Jul 25, 2009, fullsun007 from Gainesville, FL wrote:

This plant is a good choice for a shady as well as sunny locations although can wilt in the latter, during the hottest part of the day, but rebounds well. It produces several erect stalks with waxy green leaves and in the fall here in zone 8B sends 1-1.5 feet flower spikes which provide a welcome splash of color and food source for humming birds. This plant is very easy to root from softwood cuttings, it freezes to the ground and rebounds each spring.


On Jul 26, 2006, nanabon_e from Saucier, MS wrote:

I received a cutting of this plant from my daughter and grow it in Saucier, MS. I love this plant because of its low maintenance and easy care. The beauty of it is an added bonus.


On Jul 16, 2006, pdkrones from Monroe, NC (Zone 7b) wrote:

I love this plant. Three years ago, I got a start from a DG friend that I kept on the kitchen windowsill. I planted it in a shady place where the soil was not great, and it did not make it the next spring. However, the 3 cuttings I rooted did fine in a cool greenhouse, flouished and bloomed well last year, and came back again this year. Soil conditions were definitely better. However, they get wilty in the afternoon sun, even in their second year in the ground, so I have last year's cuttings in part to full shade, where they are growing well, but a little more upright. Last year's plants made it to perhaps 20' x 20". I suspect they will be bigger this year. The foliage is wonderful, pest free, glossy; and the fall flowers are unique for that time of year. Our last winter was a littl... read more


On Jun 30, 2006, mamajack from Fate, TX (Zone 8a) wrote:

i like the thick, waxy leaves. i have it in morning sun. freezes to the ground here but returns in the spring. easy to root. the only negative here is that it blooms so late in the season and is usually frozen to the ground just as it begins to bloom.


On Dec 17, 2005, sheilalarry from Punta Gorda, FL wrote:

I have one of these blooming beautifully in part shade in poor soil with almost no care except I cut back some of the slightly tattered stalks. Its foliage and flowers are just lovely.


On Jul 28, 2005, soozer from Safety Harbor, FL (Zone 9b) wrote:

Dug this up from a fellow Floridian's yard because they wanted it gone. Divided it in two and planted this Firespike in pretty much full sun areas. From the photo I posted, you can see the shiny leaves are smaller, about and inch long. The stems are shorter, about 3 feet tall, than others posted here as being planted in more shade. The red-orange flowers bloomed late winter and early this spring this year. It's the end of July and have seen no insect damage or trouble at all. Will take cuttings and try planting one in part shade. Really like this colorful trouble-free bush.


On Aug 15, 2004, Melba_Ga from Commerce, GA (Zone 8a) wrote:

I have Firespike in partial shade. This is a really pretty plant,blooms attract butterflies. Very easy to root cuttings. Mine has been cut-back several times, bounces back with very thick, green, foliage & pretty blooms.


On Aug 12, 2004, antimony35 from Prairieville, LA wrote:

hummingbirds love this plant


On May 19, 2004, TamiMcNally from Lake Placid, FL (Zone 9b) wrote:

I have some in full shade and some in part shade.

Full shade plants are about eight feet tall, dark green, and a bit thin, but still attractive.

Part shade plants are six feet tall, medium green, and thick.

In both cases, the plants spread quickly. I have had great success with cuttings and division.


On Aug 12, 2003, htop from San Antonio, TX (Zone 8b) wrote:

This plant, native to Mexico and Central America, solves the problem of having a shady area (mine are planted in dappled shade and full shade) where very few plants will grow, much less bloom. In San Antonio, it is grown for its beautiful deep green bushy tropical foliage in the spring, summer and late fall and its magnificent glow-in-the dark red blooms from early to middle August until the first freeze. Firespike (fire spike) can serve as a substitute for the hosta that tends to be devoured by snails and mealy bugs (pill bugs)in this area of Texas. However, I planted light green and white hosta in the foreround around these plants, have been vigilantly attacking the snails and mealy bugs and the hostas are doing fine. It can be grown as a tropical container plant. I would not recommen... read more


On Dec 3, 2001, Floridian from Lutz, FL (Zone 9b) wrote:

Firespike is a showy evergreen shrub with sparse, stiff branches that grow mostly straight up to about 6' tall. It has shiny dark green leaves with wavy margins and long pointed tips. The leaves are oblong, arranged opposite each other on the stem, and 4-6" long. From late summer through winter firespike produces abundant upright panicles of brilliant red tubular flowers. Firespike does well in full sun and better in partial shade. Once established it can tolerate all but the longest droughts. In frost-free areas firespike grows as an evergreen semi-woody shrub. In zones 8 and 9 it usually dies back to the ground in winter and resprouts in spring. It spreads by underground sprouting, enlarging to form a thicket, but it is easy to control and keep contained. Firespike is one of the few re... read more