Dude you need to water your plants more the sign of wilting leaves and not enough water is from dehydration and from not enough humidity. If you over water the leaves will wilt also but you know you did not over water. You should water minimum of one litre every watering if those are 5 gallon pots and 2/2.5 litres when they are flowering. You let them dry up too much and the roots are going to die which is why the leaves are dry and dead. When the plants are young you should spray them with water to help keep them humid also use a small bedroom house hold Humidifier
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