In 2023, we learned that mirlitons need partial shade when there is prolonged, intensive heat above 95 degrees. That, along with substantial ground irrigation, can get us through another Heat Dome.
If you are not lucky enough to have natural shade, a good shade cloth is the answer. It can be thrown over the vine or mounted over it. Shade cloths come in different shading percentages, and we recommend 40% cloth with grommets so it does not blow away. They are available at Amazon and most big box stores. Shop around online to find one that will last for years. An Amazon link is here.