Firespike Plant Care Tips: Growing The Odontonema Strictum

Odontonema Strictum [oh-dawn-toe-NEEM-muh, STRICK-tum] is a herbaceous plant belonging to the family Acanthaceae called firespike. 

Native to Mexico and Central America, this firespike plant boasts lovely crimson blooms and gleaming foliage. 

Firespike Plant flowers aka Odontonema StrictumPin

Other popular Acanthaceae family members include:

This evergreen shrub tends to produce deep, blood-red flowers in seasons of summer and autumn. The firespike Odontonema Strictum reminds some of overgrown salvia.

These glossy blooms look like they are made of plastic. 



Each individual flower gracing the plant is about an inch long and two-lipped. 

The flower stalk likes to provide a vivid contrast to the flower spikes as it comes in a dark purple hue.

Firespike is a long-flowering plant which is a dazzling addition to a garden. 

The blooms are the main attraction of the plant. They produce sweet nectar, attract hummingbirds, bees and butterflies all year round.  

This gorgeous flowering plant is also known by the common names including:

  • Firespike
  • Cardinal Guard
  • Scarlet Flame

Firespike Plant Care

Size and Growth

This plant can grow up to 4′ – 12′ feet tall and spreads up to 2′ – 3′ feet wide. 

The shiny, green leaves of this evergreen shrub reach a total length of 7″ – 8″ inches.

Flowering and Fragrance

The most notable feature of Odontonema Strictum is its gorgeous flowers and persistent leaves. 

This stunning floral plant features slender, bright fiery red flowers just above the foliage on erect spikes. 

In the early spring through late summer, a few spikes are present but they increase in numbers throughout the fall and winter. 

The floral property of this plant type makes it a long-blooming species in frost-free areas.

The beauty of Odontonema Strictum is further elevated by its dark green leaves which have a unique glistening appeal. 

The leaves give off a faint odor and have a slightly disagreeable taste.   

Light and Temperature

This landscape jewel is a tropical native so it likes to grow in that type of environment; which means the flowering plant strives and thrives well in a relatively hot climate throughout the year.

However, the tropical plant fails to live in frosty, cold areas and therefore, planting it in cold lands is considered a bad idea. 

Firespikes live in Hardiness USDA Zones 8 or higher, which includes the southernmost areas of Texas, Florida, and California.

The versatile and useful shrub needs partial shade to full sun for optimal performance. 

Experts suggest firespike plants require 75 – 95% of sunlight. 

If the plant is cultivated in a dry place, it needs to be watered daily to withstand long spells of drought.

Along with filtered or bright sunlight, the plant requires well-drained soil.

Watering and Feeding

Firespikes need regular water to maintain its long spikes and tubular flowers throughout the season. 

To maintain this flowering plant, fertilizing is crucial.

Fertilize 6″ – 10″ inches away from the base, three times a year with a balanced slow-release product. 

Avoid applying cheap, heavy-salted fertilizers as they damage the roots and kill the plant ultimately.

Soil and Transplanting

Red firespikes easily root in water which makes them supremely fibrous. 

However, at the time of transplanting, they often die.

A better option is to use perlite with water when transplanting firespikes. 

First of all, fill a container with enough water to keep the sand moist. 

Now dip the cuttings in rooting hormones which will help grow strong roots. 

When transplanting, leave perlite sticks to the roots and pot it up for healthy growth!

It appreciates moist, well-drained soil and is able to tolerate sandy soil.

Grooming and Maintenance

There isn’t much to taking care of firespikes once it is planted in the right soil. 

The plant loves moist and compost-based soil so ensure they are presented with this type of soil. 

The plant also lives a healthy life in full sun or partial sun. 

When planting this shrub, space the small bushes at least 24″ inches apart. 

In a few years, they will spread away into this space. 

When the branches become unruly or too long, prune them. 

Pruning of the plant is required two or three times a year.

How To Propagate Odontonema Strictum

Firespike Odontonema Strictum are easy to propagate from softwood cuttings. 

It is also propagated by cutting a branch and sticking it in the ground where a new plant will see the light of the day. 

The cuttings are rooted in the spring, which blooms by the fall season.

Please note that firspikes are propagated from seeds also.

Odontonema Strictum Pests and Diseases

This low-maintenance plant is not threatened by any pests or diseases.

Firespike Plant Uses

Owing to their lovely red blooms and dark green leaves, firepsikes make for a perfect candidate for mass planting in the landscape. 

They are also a befitting choice for the cutting garden. 

For the best effect, plant this perennial in full sun. 

This will result in heavy blooming and a stunning spectacle!

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