The temperature dependence of maximal population growth rate (r_m) is key to predicting ectotherm responses to climatic change. Matrix projection models (MPMs) are used to calculate r_m because they can incorporate variation and inherent time-delays in underlying life-history traits. However, MPM calculations can be laborious and do not reflect time’s continuous nature. Ordinary differential equation-based models (ODEMs) offer a relatively tractable alternative, but it is largely unknown whether ODEM-based calculations and MPM broadly agree when environmental variation affects temperature–dependent r_m by introducing time-delays and altering juvenile survival trajectories. We investigate differences in predicted temperature-dependent r_m from an ODEM with that calculated from MPMs using temperature– and resource-dependent life-history trait data for the mosquito vector, Aedes aegypti. We show that discrete- and continuous-time calculations of temperature-dependent r_m can vary with resource availability and are sensitive to juvenile survival characterisations, suggesting ODEMs can provide comparable temperature–dependent r_m calculations unless resources are constraining.