Hey everyone, I am making an arduino soil moisture sensor using an Arduino Uno and an fc-28 soil moisture sensor, and a normal led, how can I make my arduino power without a laptop?
If you mean battery powered, an Uno is a poor choice for a controller. The LEDs, voltage regulators and USB-serial interface suck up a "lot" of power.
Here is a Nick Gammon article on building and programming a stand alone mega 328 based controller (breadboard Uno).
Here is another of Nick's articles on building and programming for low power usage to extend battery life.
5V mobile phone charger, you probably have a few spares floating around your home. Easiest is one with USB socket as output, so you can directly plug in your Arduino.