Non-native Plants

Firespike

Odontonema tubiforme

USDA symbol: ODTU

perennial shrub

Hawaii: non-native, naturalized
Lower 48 states: non-native, naturalized
Puerto Rico: non-native, naturalized

If you’re looking to add some serious tropical flair to your garden, firespike (Odontonema tubiforme) might just be the showstopper you’ve been searching for. This eye-catching perennial shrub brings vibrant red-orange blooms and lush foliage to landscapes in the warmest parts of the United States. Firespike is a multi-stemmed shrub ...

Firespike: A Tropical Beauty for Warm Climate Gardens

If you’re looking to add some serious tropical flair to your garden, firespike (Odontonema tubiforme) might just be the showstopper you’ve been searching for. This eye-catching perennial shrub brings vibrant red-orange blooms and lush foliage to landscapes in the warmest parts of the United States.

What is Firespike?

Firespike is a multi-stemmed shrub that typically grows 4-6 feet tall and wide, though it can reach up to 13 feet in ideal conditions. This perennial plant produces glossy, dark green leaves and spectacular spikes of tubular red-orange flowers that seem to glow like flames – hence the common name firespike.

You might also see this plant listed under its botanical synonyms Odontonema strictum or Thyrsacanthus strictus in older gardening references.

Where Does Firespike Grow?

Originally from Central America and northern South America, firespike has found its way into gardens across Florida, Hawaii, and Puerto Rico. This non-native plant has established itself in these warm regions where it reproduces naturally in the wild.

  • Species observed
  • No observations

Why Consider Growing Firespike?

There are several compelling reasons gardeners in warm climates might want to add firespike to their landscapes:

  • Stunning flowers: The bright red-orange tubular blooms create dramatic vertical accents and bloom for extended periods
  • Pollinator magnet: Hummingbirds and butterflies absolutely love the nectar-rich flowers
  • Low maintenance: Once established, it’s relatively easy to care for
  • Tropical appeal: Perfect for creating that lush, exotic garden look

Growing Conditions and Care

Firespike thrives in USDA hardiness zones 9b through 11, making it suitable only for the warmest parts of the country. Here’s what this tropical beauty needs to flourish:

Light and Location

Plant firespike in partial shade to full sun locations. While it can handle full sun, some afternoon shade in extremely hot climates will help prevent stress.

Soil and Water Requirements

This shrub prefers moist, well-draining soil and doesn’t tolerate drought well once established. Based on its wetland status, firespike generally prefers upland conditions rather than consistently wet soils, though it can adapt to slightly moist conditions in Hawaii.

Planting and Maintenance Tips

  • Space plants 3-4 feet apart to allow for mature size
  • Water regularly, especially during dry spells
  • Prune after flowering to maintain shape and size
  • Protect from cold temperatures and frost
  • Apply mulch around the base to retain moisture

Landscape Uses

Firespike works beautifully as:

  • A focal point in tropical garden beds
  • Background plantings in mixed borders
  • Butterfly and hummingbird garden centerpieces
  • Privacy screening when planted in groups

Important Considerations

While firespike isn’t currently listed as invasive, it’s worth noting that this non-native plant can self-seed and naturalize in suitable climates. Responsible gardening means being mindful of how plants might spread beyond your garden boundaries.

Native Alternatives to Consider

If you’re interested in supporting local ecosystems with native plants that offer similar benefits, consider these alternatives:

  • In Florida: Wild coffee (Psychotria nervosa) or Firebush (Hamelia patens)
  • In Hawaii: Native hibiscus species or other indigenous flowering shrubs
  • In Puerto Rico: Native Anthurium species or indigenous flowering plants

The Bottom Line

Firespike can be a stunning addition to warm-climate gardens, especially if you’re aiming for that tropical paradise look and want to attract hummingbirds and butterflies. Just remember to plant responsibly, keep an eye on its spread, and consider incorporating native alternatives alongside non-native beauties like firespike for the healthiest, most balanced landscape possible.

With proper care and the right growing conditions, this fiery-flowered shrub will reward you with months of spectacular blooms and plenty of pollinator visitors to enjoy.

Odontonema tubiforme is also known as...

Often we refer to plants by their common names. When shopping for plants the scientific name is the best way to positively identify the plant species you desire. But some plants have more than one name! While it doesn't happen often, nurseries might display one name while you're searching for another. Odontonema tubiforme is also known as:

Odontonema strictum | USDA symbol: ODST
Thyrsacanthus strictus | USDA symbol: THST5

Why do some plants have more than one name? Over time plant species may be renamed for a few reasons:

  1. Botanists in different regions named the same plant without knowing it had already been classified.
  2. A species was reclassified after scientific advances in, for example, DNA analysis.
  3. Slight variations within a species are sometimes mistakenly identified as entirely new species.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" — matching plants to their ideal growing conditions, so they'll thrive with less care and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection can be if you don't have the right information. While tags on nursery plants list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. You might be surprised to learn that popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. The table below gives insight into the preferred growing conditions of this plant throughout its geographical distribution.

Region
Preferred Habitat

Caribbean (PR, VI)

Obligate Upland

Hawaii ()

Facultative Upland
Wetland Glossary
Obligate Wetland
Facultative Wetland
Facultative
Facultative Upland
Obligate Upland
Almost always occurs in wetlands
Usually occurs in wetlands but may occur in non-wetlands
Can occur in wetlands and non-wetlands
Usually occurs in non-wetlands but may occur in wetlands
Almost never occurs in wetlands

Classification

Group: Dicot
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Magnoliopsida - Dicotyledons
Subclass: Asteridae
Order: Scrophulariales
Family: Acanthaceae Juss. - Acanthus family
Genus: Odontonema Nees - toothedthread

Species: Odontonema tubiforme (Bertol.) Kuntze - firespike

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA