Musterd is a plant whose seeds and leaves are useful to us
Long answer
fruit
Variegated leafed plant is useful for demonstrating that chlorophyll is needed for photosynthesis because variegated leaf is a plant which uses chlorophyll to absorb light so it can get its color
Fertile soil, moisture, air and light
Musterd is a plant whose seeds and leaves are useful to us
Floods are useful by how plant fertilize it help the plants.
maths is useful to tell scientific theories becaus
five ways how plants are useful to us
soil and plant
Long answer
Variations in organisms can certainly be useful in plant and animal breeding. These variations lead to adaptions to the environment.
A touch-me-not plant is useful for entertainment, as a 'pet' or for illustrating the unusual feature of fast movement in a plant.
It can tell you if you have a temperature...
they tell you where you are
rainwater
Feed some people