North America Native Plant

California Waterwort

Botanical name: Elatine californica

USDA symbol: ELCA

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Elatine californica A. Gray var. williamsii (Rydb.) Fassett (ELCAW2)   

California Waterwort: A Tiny Native for Specialized Water Gardens If you’re looking for a showstopper to anchor your garden beds, California waterwort probably isn’t your plant. But if you’re creating a specialized wetland habitat or have a natural seasonal pond on your property, this diminutive native might just be the ...

California Waterwort: A Tiny Native for Specialized Water Gardens

If you’re looking for a showstopper to anchor your garden beds, California waterwort probably isn’t your plant. But if you’re creating a specialized wetland habitat or have a natural seasonal pond on your property, this diminutive native might just be the perfect addition to your aquatic plant collection.

Meet the California Waterwort

California waterwort (Elatine californica) is one of those plants that proves good things come in small packages – very small packages. This annual forb is a true native of the western United States, naturally occurring across Arizona, California, Idaho, Montana, Nevada, Oregon, Utah, and Washington. As a member of the waterwort family, it’s perfectly adapted to life in and around water.

You might also encounter this plant listed under the synonym Elatine californica var. williamsii in some older botanical references, but they’re referring to the same charming little wetland specialist.

What Does It Look Like?

Let’s be honest – California waterwort won’t win any beauty contests in the traditional sense. This low-growing annual forms small mats with tiny oval leaves and produces minuscule white flowers that you’ll need to look closely to appreciate. Think of it as nature’s version of a living carpet rather than a dramatic focal point.

The plant’s growth habit is perfectly suited to its wetland lifestyle, staying low to the ground and spreading horizontally rather than reaching skyward.

Where and Why to Grow California Waterwort

Here’s where things get interesting – and where most gardeners will need to pause and consider whether this plant fits their situation. California waterwort is classified as an obligate wetland species across all its native regions, meaning it almost always occurs in wetlands and requires consistently wet conditions to thrive.

This plant is ideal for:

  • Bog gardens and constructed wetlands
  • Edges of natural or artificial ponds
  • Seasonal wetland restoration projects
  • Rain gardens that stay consistently moist
  • Native plant enthusiasts with specialized water features

It’s definitely not suited for typical flower beds, container gardens, or landscapes without reliable moisture. Think of it as a specialist rather than a generalist – it does one thing very well, but that one thing is pretty specific.

Growing Conditions and Care

Successfully growing California waterwort is all about recreating its preferred wetland conditions:

Moisture: This is non-negotiable. The soil must remain consistently moist to saturated. If you can’t guarantee this level of moisture year-round, this plant isn’t for you.

Light: California waterwort tolerates full sun to partial shade, making it fairly flexible as long as the moisture requirements are met.

Climate: Hardy in USDA zones 4-9, this annual can handle a wide range of temperatures but relies on seasonal moisture patterns.

Soil: Prefers muddy, saturated soils typical of wetland environments. Heavy clay or organic-rich soils that hold water work well.

Planting and Maintenance

As an annual, California waterwort completes its entire life cycle in one growing season, so you’ll need to either allow it to self-seed or replant each year. The tiny seeds are naturally adapted to wetland conditions and will germinate when conditions are right.

Maintenance is minimal once established – nature handles most of the work if you’ve created the right conditions. The main task is ensuring consistent moisture levels and allowing space for the plant to form its natural low mats.

Wildlife and Ecosystem Benefits

While California waterwort may not be a major pollinator magnet due to its tiny flowers, it plays an important role in wetland ecosystems. As part of a diverse native wetland plant community, it contributes to habitat complexity and may provide food and shelter for small aquatic organisms and insects.

The Bottom Line

California waterwort is a plant for the specialized gardener – someone who’s either blessed with natural wetland conditions or committed to creating and maintaining them artificially. It’s not going to work in most typical garden settings, but for those interested in native wetland restoration or who have appropriate water features, it can be a valuable addition to a diverse plant community.

If you don’t have the right conditions for California waterwort but want to support native plants, consider exploring other western natives that are better suited to typical garden conditions. Your local native plant society can help you find alternatives that will thrive in your specific situation while still supporting local ecosystems.

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 work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags 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. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Arid West

OBL

Obligate Wetland - Plants with this status almost always occurs in wetlands

Great Plains

OBL

Obligate Wetland - Plants with this status almost always occurs in wetlands

Western Mountains, Valleys, and Coast

OBL

Obligate Wetland - Plants with this status almost always occurs in wetlands

California Waterwort

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Dilleniidae

Order

Theales

Family

Elatinaceae Dumort. - Waterwort family

Genus

Elatine L. - waterwort

Species

Elatine californica A. Gray - California waterwort

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