North America Native Plant

Wedge Sandmat

Botanical name: Chamaesyce deltoidea serpyllum

USDA symbol: CHDES

Life cycle: perennial

Habit: subshrub

Native status: Native to the lower 48 states  

Synonyms: Chamaesyce serpyllum Small (CHSE10)  âš˜  Euphorbia deltoidea Engelm. ex Chapm. var. serpyllum (Small) Oudejans (EUDES)   

Wedge Sandmat: A Rare Florida Native Worth Protecting Meet wedge sandmat (Chamaesyce deltoidea serpyllum), one of Florida’s most elusive native plants. This tiny perennial herb might not win any beauty contests, but it holds a special place in the hearts of conservationists and native plant enthusiasts who understand its incredible ...

Rare plant alert!

Region: United States

Status: S2T1: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ Endangered: In danger of extinction throughout all or a significant portion of its range. ⚘

Region: United States

Wedge Sandmat: A Rare Florida Native Worth Protecting

Meet wedge sandmat (Chamaesyce deltoidea serpyllum), one of Florida’s most elusive native plants. This tiny perennial herb might not win any beauty contests, but it holds a special place in the hearts of conservationists and native plant enthusiasts who understand its incredible rarity and ecological significance.

What Makes Wedge Sandmat Special?

Wedge sandmat is a low-growing forb herb that stays close to the ground, creating a subtle carpet of small leaves and inconspicuous flowers. As a member of the spurge family, it shares characteristics with other Chamaesyce species but has its own unique charm. You might also see it listed under its botanical synonyms Chamaesyce serpyllum or Euphorbia deltoidea var. serpyllum in older reference materials.

This isn’t your typical garden center plant – wedge sandmat is found exclusively in Florida, making it a true Sunshine State endemic. Its natural habitat consists of the state’s coastal areas, where it has adapted to thrive in sandy soils and bright sunshine.

The Conservation Reality

Here’s where things get serious: wedge sandmat is listed as Endangered in the United States, with a Global Conservation Status of S2T1. This means it’s hanging on by a thread in the wild, facing significant threats to its survival. If you’re considering adding this plant to your landscape, it’s crucial to understand the responsibility that comes with growing such a rare species.

Should You Plant Wedge Sandmat?

The short answer is: only if you can source it responsibly and are committed to its conservation. This plant isn’t suitable for casual gardeners looking for easy-care groundcover. Instead, it’s perfect for:

  • Dedicated native plant conservationists
  • Specialized restoration projects
  • Educational native plant gardens
  • Coastal habitat restoration efforts

Given its endangered status, never collect wedge sandmat from the wild. Only obtain plants or seeds from reputable native plant nurseries that propagate from ethically sourced stock.

Growing Wedge Sandmat Successfully

If you’re up for the challenge, wedge sandmat has very specific needs that mirror its natural coastal Florida habitat:

Climate Requirements: This plant is only hardy in USDA zones 9b through 11, essentially limiting it to South Florida’s subtropical climate. It simply won’t survive freezing temperatures.

Soil Preferences: Sandy, well-draining soil is absolutely essential. Think beach sand rather than rich garden loam. The plant has evolved in coastal conditions and won’t tolerate heavy, moisture-retentive soils.

Light Needs: Full sun exposure mimics its natural habitat where it grows in open, sunny locations without shade from larger plants.

Water Requirements: Once established, wedge sandmat prefers minimal supplemental watering. It’s adapted to periods of drought and can be damaged by overwatering.

Landscape Role and Design Ideas

Wedge sandmat works best as a specialized groundcover in native plant gardens designed to showcase Florida’s unique flora. Its low-growing habit makes it suitable for rock gardens, coastal plantings, or as part of a larger native plant collection. Don’t expect showy flowers or dramatic foliage – this plant’s appeal lies in its rarity and conservation value rather than ornamental impact.

A Plant Worth Preserving

While wedge sandmat may not be the flashiest addition to your garden, growing it responsibly contributes to the conservation of Florida’s unique botanical heritage. Every plant grown in cultivation helps preserve genetic diversity and reduces pressure on wild populations. Just remember – with great rarity comes great responsibility. Only pursue this plant if you’re truly committed to its care and conservation.

For most gardeners interested in supporting Florida’s native ecosystem, consider more readily available native alternatives that can provide similar groundcover functions while still supporting local wildlife and maintaining the authentic character of Florida’s natural landscapes.

Wedge Sandmat

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Euphorbiales

Family

Euphorbiaceae Juss. - Spurge family

Genus

Chamaesyce Gray - sandmat

Species

Chamaesyce deltoidea (Engelm. ex Chapm.) Small - wedge sandmat

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