To produce viable seeds, plants must simultaneously allocate mass to other reproductive tissues; however, it remains unclear how big these investments are, relative to seeds, and how much the balance of investment across diverse species reflects broader variation in their life history strategies. In particular, species are known to vary in their seed mass, and the amount they invest in pollen attraction versus seed provisioning. We quantified overall reproductive investment and its partitioning among different reproductive tissues for 14 perennial species in a recurrent-fire heath community. Integrating two lineages of evolutionary theory led to the prediction that relative investment in different reproductive tissues would be correlated with a species’ seed size, and the data supported this. Species with larger seeds were found to mature a smaller proportion of ovules, to expend more of pre-zygotic investment on discarded tissues, and to invest more in seed provisioning compared to pollen attraction. A little more than half of this correlation is phylogenetically conservative, reflecting the tendency for many species in Proteaceae to have large seeds, low seed set and relatively lower investment in pollen attraction. The total cost of accessory tissues – reproduction-related mass not directly invested in the seed – ranged from 95.8% to 99.8% of total investment for species in this study. Counting only seeds thus substantially underestimates total reproductive investment. Many studies have established that the seed size of a species positions it along a colonization-competition life-history spectrum. Here we have shown that relative investment in pollen-attraction versus provisioning tissues and in successful versus discarded ovules are also associated with seed size. The seed size spectrum among angiosperms is therefore connected with a spectrum of reproductive allocation strategies.