Soil and climate are the two most important factors that affect vegetation.
With regards to climatic factors, two main elements are important, namely; rainfall and temperatures particularly their seasonal distribution. Specifical the length of the dry season.
In a broad sense, rainfall determines the vegetation type, abundant rainfall tends to produce forest, light rainfall grassland, and meagre rainfall causes scrubs and deserts.
Low temperature tends to result in slower plant growth while higher temperatures leads to produces more luxuriant growth.