What is the sensor data format?

I have a device that is publishing a JSON string of various status values.

In my sensors.yaml include file, I have this entry:

  - platform: mqtt
    name: "Garden_Status"
    force_update: true
    state_topic: "garden2/statusJson"

In Developer Tools, States, I can see the sensor, but the data is the whole JSON string:
{"temp":"77.68","wet":"114","raw":"861","rssi":"-66","sleep":"10"}
How can I split it into attributes to use in an automation, for example?
(I am guessing that I need to use a template, but how?)

Use the value template option. e.g.

sensor:
  - platform: mqtt
    name: "Garden"
    state_topic: "garden2/statusJson"
    json_attributes_topic: "garden2/statusJson"

There is an example here: https://www.home-assistant.io/integrations/sensor.mqtt/#json-attributes-template-configuration

Also please format your pasted code.

Thanks a heap- I am glad it was this simple.