Action after 3 measurments in row

Hello,
He is working on a garden measurement project with the measurement of soil moisture. As you probably know, the accuracy of the cheapest sensors is not big, so I'm faced with the problem of too frequent watering the soil.
My question is.
how to write in the arduino program to start watering after detection of too dry soil in 3 consecutive measurements carried out at intervals of 30 min.

Define a count variable. Make it start at zero.

Every time you take a measurement, if it's dry add one to the count variable. Else set it to zero.

If the variable reaches 3, start your watering routine.

I have to say that these are my first steps in arduino. Could anyone type this?

Could you post your original sketch?

John_Fajny:
I have to say that these are my first steps in arduino. Could anyone type this?

You type. We'll correct.