This is the list of food by hour of each fruit (1 farm ):
For the last 3 , is replanting the same fruit each time during 1 hour , of course this is only posible if you have enougth dragons to pay for it
This is the cost of planting 1 hour of each fruit (1 farm)
Impruberries are the fruit to go if you are only playing DS. You can plant 7 farms, collect money from 4 habitats then harvest and replant all in 30 seconds cycles.
Plant Buffbeets if you have bombs or dynamite. (i use 4 in 3 minutes)
If you are competing in a tourney, Fireaples or Rushrooms have the same 1 hour cycle.
Upgrapes are the best fruit but also the most expensive (7 farms = 336 000 silver and 4200 food each hour) but the 10 minute cycle is akward unless you are watching videos or doing something that can be paused.
i personally plant 5 Rushrooms + 2 Firapples (131300 silver for 1600 food each hour) i take 5 minute breaks each hour to play DS