Hi Mapo, Dhania , is relatively loved herb and common to most kitchens, your desire to grow it for agribusiness purposes is good idea. Some of the trickier challenges you'll definitely encounter specifically on parsley are:-
-Seeds take longer to germinate( 3-4weeks)
-Parsley performance is adversely affected by low soil PH I.e conditions between 5.5- 7 are best suited
-This crop also attracts whiteflies more than other crops..
-parsley records better production in warm temperatures therefore one doing it under green- house technology will have better results.
Marketing
As I began by saying parsley is widely loved while not commonly produced this itself present a competitive advantage to any producer more so from Bungoma. Just to appetize you more all 7+ super markets in Bungoma town, three star,four star hotels and restaurant in Bungoma alone will be stocking your produce as well as local markets around you.
NB longer germination time is reduced by soaking seeds in warm water for 24 hours.
-Its important to know soil PH. and if need be amendment be done appropriately in addition Dhania loves soils wih high level of decompost organic manure .Thanks