These Life Hacks Will Get You Through This Disgustingly Hot Summer. Some of these can work for more than what is pictured. For example, the Vodka bottle. You could more than likely use that trick with any other beverage.
Make plastic bottles rigid to use as a cloche by forming a reinforcing ring around edge Place cloches over young plants & keep bottle caps off during day to prevent heat build up. Replace caps at night to trap heat and keep plants warm.