North America Native Plant

Dense Crowngrass

Botanical name: Paspalum densum

USDA symbol: PADE6

Life cycle: perennial

Habit: grass

Native status: Native to Puerto Rico  

Dense Crowngrass: A Caribbean Native for Wet Spots in Your Garden If you’re dealing with a persistently soggy spot in your Puerto Rican garden, dense crowngrass (Paspalum densum) might just be your new best friend. This native perennial grass isn’t trying to win any beauty contests, but it’s got some ...

Dense Crowngrass: A Caribbean Native for Wet Spots in Your Garden

If you’re dealing with a persistently soggy spot in your Puerto Rican garden, dense crowngrass (Paspalum densum) might just be your new best friend. This native perennial grass isn’t trying to win any beauty contests, but it’s got some serious practical charm that makes it worth considering for the right spot.

What is Dense Crowngrass?

Dense crowngrass is a true Puerto Rican native – born and raised right here in the Caribbean. As its name suggests, this perennial grass forms dense clumps of narrow, linear leaves that create a lush, textured appearance. It’s part of the Paspalum genus, which includes many important grasses found throughout tropical and subtropical regions.

Where Does it Grow Naturally?

This grass calls Puerto Rico home, thriving in the island’s wetland areas and marshy spots. You’ll find it naturally occurring in areas that stay consistently moist or even flooded periodically.

Why Consider Dense Crowngrass for Your Garden?

Here’s where this humble grass really shines. Dense crowngrass is what we call an obligate wetland plant, which is a fancy way of saying it absolutely loves wet feet. If you have a spot in your garden that’s always soggy – maybe a low area that collects rainwater or a spot near a downspout – this grass could turn that problematic area into an asset.

The benefits include:

  • Natural erosion control with its dense root system
  • Requires zero irrigation once established (assuming you plant it in the right wet spot)
  • Supports local ecosystem as a native species
  • Low maintenance once happy in its location
  • Adds natural texture and movement to water features

Perfect Garden Settings

Dense crowngrass isn’t for every garden situation, but it’s perfect for:

  • Rain gardens and bioswales
  • Pond edges and water garden margins
  • Native plant gardens focusing on Caribbean species
  • Wetland restoration projects
  • Areas with drainage problems
  • Natural erosion control along streams or slopes

Growing Conditions and Care

The key to success with dense crowngrass is understanding its non-negotiable need for moisture. This plant thrives in USDA hardiness zones 10-11, making it suitable for Puerto Rico’s tropical climate year-round.

Ideal growing conditions:

  • Consistently moist to wet soil (will tolerate periodic flooding)
  • Full sun to partial shade
  • Any soil type, as long as it stays wet
  • High humidity (naturally provided in Puerto Rico)

Planting and Maintenance Tips

The good news is that once you get dense crowngrass established in the right location, it’s pretty much a set-it-and-forget-it kind of plant.

Planting: Choose the wettest spot available in your garden. Spring is typically the best time to plant, allowing the grass to establish before any drier periods.

Watering: If planted in an appropriately wet location, additional watering shouldn’t be necessary. The challenge with this plant is usually providing enough moisture, not too much.

Fertilizing: Minimal fertilization is needed. Wetland plants like this are adapted to nutrient-poor conditions and can actually be harmed by over-fertilizing.

Pruning: You can cut back the grass in late winter if you want to refresh its appearance, but this isn’t necessary for plant health.

Is Dense Crowngrass Right for Your Garden?

Dense crowngrass won’t work in every garden, and that’s okay. It’s a specialist plant for specialist conditions. If you have consistently wet soil and want to work with nature rather than against it, this native grass could be an excellent choice. It’s particularly valuable if you’re trying to create habitat for local wildlife or manage stormwater runoff naturally.

However, if your garden tends toward the dry side, you’ll want to look for other native Puerto Rican plants that are better suited to drier conditions. Remember, the best native plant garden works with your specific site conditions, not against them.

Dense crowngrass may not be the showiest plant in the native plant world, but sometimes the most valuable plants are the ones that quietly do important work behind the scenes – like preventing erosion, managing water, and providing habitat for local wildlife.

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

Caribbean

OBL

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

Dense Crowngrass

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Poaceae Barnhart - Grass family

Genus

Paspalum L. - crowngrass

Species

Paspalum densum Poir. - dense crowngrass

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