Summer has come and I don't know what to do

Solution 1:

According to the wiki, wilting plants will return to normal in Autumn even without fertilizer that they require to perk up in Summer.

The game really never seems to encourage players to bunker down and wait out seasons, but rather to adapt to the season, and get out there to explore. How about a wearable Ice Cube, Straw Hat, frozen Thermal Stone?

An Ice Flingomatic can protect your structures and things, but smoldering objects can be cooled with Ice, Fertilizer, an Ice Staff, or your hands at the cost of health. The wiki suggests as you did to avoid camp as a last resort, as they will only begin to smolder when the player is nearby.