wat up wit ma plant got pixx

i live in tucson az first time grower using organic mg for soil no nutes and i water once a day about a cup of water i grow out side the temp is like 90-100 late mornin to late afternoon and 80 at night and like 70 in the early mornnn plz help

the soil looks dry and heat at those temps have an adverse affect on mj.

temp should be ranging from 70 to 80.