The Flora of Ashmore and Cartier Islands consists of 16 families, 23 genera and 27 species. Four of these species are introduced and naturalised. In addition, two species have been introduced but not naturalised. The vegetation is dominated by shrubs, grasses and creepers. The vast majority of species have seeds that are very easily transported by the wind, birds or the sea.
The following plant taxa occur on the islands of Ashmore Reef:
| Taxon | Common name | Remarks |
|---|---|---|
| Amaranthus interruptus | ||
| Heliotropium foertherianum | ||
| Boerhavia albiflora | ||
| Boerhavia burbidgeana | ||
| Boerhavia glabrata | ||
| Boerhavia repens | ||
| Cassytha filiformis | ||
| Cenchrus brownii | Naturalised | |
| Cenchrus ciliaris | Naturalised | |
| Cleome gynandra | ||
| Cordia subcordata | Tou | |
| Digitaria mariannensis | ||
| Eragrostis elongata | ||
| Guettarda speciosa | ||
| Ipomoea macrantha | ||
| Ipomoea pes-caprae subsp. brasiliensis | ||
| Lepturus repens | ||
| Portulaca oleracea | Common Purslane | Naturalised |
| Portulaca tuberosa | ||
| Scaevola taccada | ||
| Sesbania cannabina var. cannabina | Naturalised | |
| Sida pusilla | ||
| Spinifex littoreus | ||
| Sporobulus virginicus | ||
| Suriana maritima | ||
| Thalassia hemprichii | ||
| Tribulus cistoides |
In addition to these, Zea mays (Maize) and Cocos nucifera (Coconut) have been introduced by visiting Indonesian fishermen as food sources, but these are not naturalised.
Cartier Island is unvegetated. The only recorded plant is the seagrass Thallassia hemprichii, which forms meadows in pockets of sand among the reef.