The Agriculture Domain of ERPNext comes with features to record crops and land, track plant, soil, water, weather analytics, and even track diseases and fertilizers. You can check out the following topics after this brief introduction to the agriculture module in ERPNext.
Using bench, install ERPNext as mentioned here.
Once ERPNext is installed, add agriculture app to your bench by running
$ bench get-app agriculture
After that, you can install agriculture app on required site by running
$ bench --site demo.com install-app agriculture
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