The species is likely to be pollinated by bees and the yellow flowers turn reddish brown after pollination.

Argyrolobium angustissimum is considered to be a fire ephemeral. This means that the species is found in high densities the first year after a fire (Rutherford et al. 2011). Such species are well known in the Fynbos Biome where fire plays an important role in maintaining diversity. Fire ephemerals are pioneer species that sprout after fire and are then generally present for anything from 3 months to 4 years. The seeds produced during this short life span persist in the soil for years between fires but may germinate occasionally if the soil is disturbed.

Research has shown that smoke acts as the main seed germination compound amongst others, such as temperature, moisture and light (Baker et al. 2005). Smoke-treated Argyrolobium lunare seedlings, germinated within 4 to 6 weeks.

Figure 4. Argyrolobium angustissimum growing in a disturbed area along a pathway.