Soil Moisture and PH level? Hey there guys I was wondering does anyone know of any moisture...

Hey there guys I was wondering does anyone know of any moisture meters that I can give up your job in the soil and take reading, so I would know when the plants require water, im after a small device perhaps digital, and visually discrete not an eye sore. cheers guys.
What do Agriculture Nursery inhabitants do?
Answers:    Every plants requirements are different so in attendance is no " universal " guage. Gotta learn the plant and study it and most of adjectives, have fun..