describe your potting soil ....
a shovel full of dirt taken from yard ?
is it bagged potting soil ?
bagged top soil ?
cactus potting soil ?
have you amended the soil ? .........added stuff like: pumice, perlite, rocks, pebbles, large grain sand ??
when you water ...are the plants watered thoroughly & saturated ? ....and does water drain freely out of the pot ?
reason I ask ...the weather where I live - is nearly the same as it is in S Florida ...minus the sea-breeze .... humidity and dew point about the same too ....
my plants are in full sun for about 6 hours a day ....and part shade in the morning ...then shade about 2 hours before sunset
and I water once every 7 - 10 days - thoroughly & saturated .... rainfall counts as a watering day
how much water is "thoroughly & saturated" ?
imagine the volume of the pot ...lets guess and say the volume is 4 cups ...no need for exactness & the actual size of the pot or what is planted in the pot doesn't matter ..what does matter is the volume ....
when watering, water at least 4 cups worth ...