North America Native Plant

Narrowleaf Water-starwort

Botanical name: Callitriche intermedia

USDA symbol: CAIN52

Habit: forb

Native status: Native to Greenland  

Narrowleaf Water-Starwort: A Tiny Arctic Aquatic for Specialized Gardens Meet narrowleaf water-starwort (Callitriche intermedia), one of nature’s most specialized little aquatic plants. This diminutive forb might not win any beauty contests, but it’s got a fascinating story and a very particular niche in the gardening world. If you’re dreaming of ...

Narrowleaf Water-Starwort: A Tiny Arctic Aquatic for Specialized Gardens

Meet narrowleaf water-starwort (Callitriche intermedia), one of nature’s most specialized little aquatic plants. This diminutive forb might not win any beauty contests, but it’s got a fascinating story and a very particular niche in the gardening world. If you’re dreaming of creating an authentic Arctic water feature or live in the far northern reaches of North America, this unassuming plant might just be your perfect match.

What Makes Narrowleaf Water-Starwort Special

Callitriche intermedia is native to Greenland and select northern regions, making it one of the most cold-hardy aquatic plants you’ll encounter. As a forb, it’s a non-woody plant that lacks significant woody tissue, but don’t let its humble classification fool you – this little survivor has adapted to thrive in some of the planet’s most challenging aquatic environments.

The plant forms small rosettes of narrow, linear leaves that float or remain submerged in shallow water. While its tiny white flowers won’t stop traffic, they serve their purpose in this harsh landscape where every bit of reproduction counts.

Should You Grow Narrowleaf Water-Starwort?

Here’s where things get interesting – and a bit challenging. This plant is incredibly specialized, and most gardeners will find it impractical for their needs. However, there are some specific situations where it shines:

  • You live in USDA zones 1-4 and want authentic native aquatic plants
  • You’re creating a specialized Arctic or subarctic garden theme
  • You have a cool water feature and want something truly unique
  • You’re involved in habitat restoration in northern regions

For most gardeners, especially those in temperate or warm climates, this plant simply won’t be suitable. It requires consistently cool water temperatures and won’t tolerate the warm conditions found in most garden ponds.

Growing Conditions and Care

If you’re determined to grow narrowleaf water-starwort, here’s what you need to know:

Essential Growing Requirements:

  • Water: Must have consistently moist to submerged conditions
  • Temperature: Requires cool water temperatures year-round
  • Hardiness: Thrives in zones 1-4, struggles in warmer areas
  • Light: Full sun to partial shade
  • Soil: Grows in muddy substrates of ponds, streams, or bog areas

Planting and Maintenance Tips:

  • Plant in shallow water (6 inches deep or less)
  • Ensure water doesn’t freeze solid to the bottom
  • Minimal fertilization needed – it’s adapted to nutrient-poor conditions
  • Allow natural spreading through the water feature
  • No pruning required – it stays naturally small

Wildlife and Ecological Benefits

While narrowleaf water-starwort may seem insignificant, it plays an important role in its native ecosystem. In the harsh Arctic environment, every plant matters for providing oxygen in aquatic systems and potential food sources for waterfowl and other wildlife adapted to these extreme conditions.

Alternative Options for Most Gardeners

Unless you’re gardening in the far north, you’ll likely want to consider other native aquatic plants better suited to your region. Look for local water-starwort species, native pond weeds, or other aquatic plants native to your specific area that can provide similar ecological functions without the extreme climate requirements.

The Bottom Line

Narrowleaf water-starwort is a fascinating example of plant adaptation to extreme environments, but it’s definitely not for every gardener. If you live in the Arctic or subarctic regions and want to create an authentic native water feature, this little plant could be a perfect addition. For everyone else, it’s better appreciated from afar while you focus on aquatic natives better suited to your local climate and conditions.

Sometimes the most interesting plants are the ones that remind us just how diverse and specialized the plant kingdom can be – even if we can’t grow them in our own backyards!

Narrowleaf Water-starwort

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Callitrichales

Family

Callitrichaceae Link. - Water-starwort family

Genus

Callitriche L. - water-starwort

Species

Callitriche intermedia Hoffm. - narrowleaf water-starwort

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