Probably feet or yards, since garden hoses are long.
You can probably estimate by it's appearance. They come in standard sizes at 25' increments, Example, 25, 50, 75, etc.
kilometer
Kilometers
Time
meeters?
a millimeter
Millimetre.
The meter.
The measurement you need in order to fence a garden is the garden's perimeter. That's a length, and it can be expressed in any length units. For a typical home garden, feet or meters would be most convenient.
Cm .
A kilometre.
Centimeters
Centimeters
Time
meeters?
a millimeter
Millimetre.
the metric system
Milligrams
Inches, millimetres or centimetres.