Synemon plana (golden sun moth) is a small diurnal moth from the family Castniidae, now listed as endangered in all regions of southeastern Australia in which it occurs. This study details an attempt to restore the native grassland habitat of S. plana at one site by increasing the cover of its probable food plant, Austrodanthonia eriantha (wallaby grass), to at least 40%, the average percentage cover determined from all currently inhabited sites. The percentage cover of A. eriantha increased when seedlings were planted, although there was no significant increase in cover by seeding caryopsides (dispersal units) or by weeding. However, combining weeding with planting seedlings, or seeding increased cover by 22% and 27% to 43% and 64%, respectively. Two hundred caryopsides per square meter (compared with only 49 seedlings/m2) were required to increase cover to at least 40% due to the low viability of seeds and low germination in the field. Therefore, to restore grasslands dominated by A. eriantha as suitable habitat for S. plana, seedlings should be planted and weeds removed.