I lived without refrigeration on some of the boats I had, and some that I worked on. To keep a variety of fruit and exotic herb flavored beverages around, I made shrub syrups, which are a tart and sweet flavour concentrated syrup make from fresh ingrediants to preserve seasonal flavours long term. You can use shrubs to flavour soda water, if you have a soda stream or if you have bottles of carbonated water, you can use it to flavour water, or mix in cocktails. You can also use it to sweeten plain teas, or in salad dressings or as a glaze for cooked meats. The shrub syrup has many uses. Here are the flavours I make regularly.
Sugar Plum Spice
Sweet Dark Cherry