A common reason campers choose hammocks instead of tents is that they are far more comfortable and cooler than their counterparts. That is perfectly fine for the summer months as your hammocks would let you sleep more comfortably regardless of the heat.
However, you will have to ensure that your hammock has proper insulation during the colder months of the year. There are many ways to do this. For instance, you can put in a space blanket underneath to keep the cold air off. Of course, you can also choose a hammock with additional layers of insulation.