So we know, that the indicator on farm, and Cattle ranch is ♥♥♥♥♥♥♥t. But how it works in reality?

For the farm. I have no idea, but it checks a part of the field, and not the buildings itself. In order to maximize it's effect without farm-stacking you need to place it like this:

https://steamuserimages-a.akamaihd.net/ugc/764972329062730363/94726F0CBA1D50F559E9C6CDAEB7776F633874F5/

The top ones get 50% as it shows. 2. row gets 70%. 3. row get 80%. 4. row gets 60%. And the bottom one gets 40%.

Now the Cattle ranch upgrade works similar. It checks part of the field. In order to make it work. You need to place it DIRECTLY at the SIDE (not working on top, or bottom) of a farm. Like this:

https://steamuserimages-a.akamaihd.net/ugc/764972329062769305/9AC46EC707380659222F5F66EF6049BAC0419EEA/

A picture of maximised cattle upgrade, and multi-culture bonuses:

https://steamuserimages-a.akamaihd.net/ugc/764972329062769506/5529002AB8FFF4F2348BC5047B32624DCC59DAE3/

Extra tip: if you make this layout, then place the sugar into the 2., or 3. row to maximize it's upgrade, and forget the pineapple upgrade since you only have one of that kind.