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The seasonal ontogeny and phenology of Sparaxis grandifloraspp. fimbriatawere examined along with various population parameters for this synanthous geophyte which possesses an annual storage organ. It was found that the majority of plants in the sample were less than seven years old with a maximum age determined at eighteen years. Age was successfully determined by examining subterranean markers (tunics) and it was found that the plants do not generally flower before they are four years old and have a ‘critical minimum corm biomass’ of 0.37g dry matter. Corm size is related to depth of burial until reproductive maturity is reached, with over 80% of the corms found in the organic profile which extends to 3cm below the soil surface. The seasonal allocation of dry matter to the various plant parts indicated the efficient mechanisms adopted by this species to cope with the mediterranean climatic conditions and the low soil nutrient levels.

The seasonal biomass and resource allocation patterns of a perennial geophytic species, Haemanthus pubescenssubspecies pubescens,were investigated. Four phenophases for the species were identified and the annual patterns of dry mass and resource allocation were identified from individuals sampled from natural populations. From the results, four general resource allocation patterns were identified: (1) mobile macronutrients (N, P and K) and Cu; (2) immobile macronutrients (Mg and Ca) and Mn; (3) soluble carbohydrates, starch, Zn and Fe; and (4) Na, all with their own distinctive allocation patterns. This study confirms distinct allocation patterns between the resources and biomass. Furthermore, it was found that environmental constraints contributed towards the differential seasonal allocation patterns of the resources and biomass. The development of an underground storage organ is regarded as an evolutionary mechanism to cope with soils of a low nutrient status, characteristic of the Cape fynbos, and as a strategy for the protection of dry matter and resources against seasonal periodic droughts and fires.