To sterilize the canning jars, separate jars, lids, and rims. Put them in a boiling water and simmer for 10 minutes. Remove from the water and let them cool and dry on a clean kitchen towel.
Juice your Meyer lemon to make about 2-1/2 cup. Strain the juice in a fine mesh to catch any seeds or pulp; discard them.
Mix 2-1/2 cup of Meyer lemon juice and 2 cups sugar in a pot over medium heat. Whisk the mixture and simmer until the sugar dissolves. When the syrup starts to boil, remove from heat.
Pour syrup to the prepared jars, leaving about 1/2 inch from the top. Make sure to wipe clean the rims of the jars.
Cover with lids and tighten. Put the jars back into the simmering water and boil for 5 minutes. You should hear the lid making a popping sound. That's a good sign that your jars are well sealed.
Let the jars cool, and store in a dark place up to 1 year.
To make 1 serving of lemonade, mix 1/4 cup of syrup to 1 cup of water. Add ice and enjoy!
Notes
To freeze the homemade lemonade syrup, you don't need to sterilize the jars. Just pour syrup into the clean jars and let cool completely. Cover with lids and store in the freezer up to 3 months.Once the jar is opened, store the leftover syrup in the fridge. Consume within a week.