What is the difference between the use of the sein-passive and the werden-passive?

When using the sein passive, you are using the past participle of the verb as an adjective. For instance; Die Wiese ist mit Blumen bedeckt. This sentence uses the sein-passive and translates as 'the meadow is covered with flowers.' Therefore, 'covered' is used as an adjective. When using the werden-passive, you are describing an action happening to something. For instance; Die Wiese wird mit Blumen bedeckt. This sentence uses the present passive of werden and translates as 'the meadow is being covered with flowers' i.e, at this time the meadow is experiencing being covered by flowers. This is different to the sein-passive which merely describes the state of the meadow.