It a desert that is irrigated.
Turkana do not even know the value of farming.
They wont mind.
Beside Turkana themselves can become farmers....but someone need to invest in harvesting the underground water
Kericho or Kiambu contrary to your thinking are NOT ideal for most agriculture except maybe tea.
Most crops do well in sun-baked turkana with good soils - they require sunlight, warmth and some water - and good soil.
Turkana has some of the best soil...and it so huge...it enough for everyone.
California is not a desert by any stretch. It is a verdant well watered osasis. Largest produce of fruits and vegetables in tehe united states.
Turkana may have all the resources you mentioned but it is for the local community, foreigners are not invited.
Devolution is greatest thing that happened to this country.