Low on the list of priorities should be annuals -- plants that only live for one growing season.

排在首位的应该是一年生植物——只存活一个生长季的植物。

This watering rule is for plants whose roots are mostly in the upper 30 cm of soil, which includes most annual vegetable and flower plants.

这条浇水规则适用于根系大多位于土壤表层30厘米的植物，其中包括大多数一年生蔬菜和花卉植物。

Linnaeus has calculated that if an annual plant produced only two seeds—and there is no plant so unproductive as this—and their seedlings next year produced two, and so on, then in twenty years there would be a million plants.

林奈计算过， 如果一株一年生植物只结出两颗种子——没有哪一种植物的产量比它低——而它们的幼苗明年结出两颗，依此类推，那么二十年后将有一百万株植物。