Thoroughly scrub the cucumbers to remove any dirt. Cut a 1/4 inch slice off the blossom end of each cucumber to help maintain their texture during pickling.

Prepare the preserving jars by washing them thoroughly and sterilizing them. You can follow your preferred canning book instructions for this process. I always make sure the jars are completely clean—this is vital for successful pickling.

Combine the water and vinegar in a large saucepan. Bring the mixture to a boil over high heat, then reduce the heat and let it simmer while you prepare the jars. Keeping the liquid hot will help fill the jars more quickly and safely.

Working with one jar at a time, place 3 dill heads and some greens, 2 peeled garlic cloves, and 2 fresh chili peppers (if using) into the jar. Add 1 tablespoon pickling salt and 1 teaspoon mixed pickling spices. Then, pack the prepared cucumbers (from Step 1) tightly into the jar, leaving about 1 inch of headspace at the top. Pour the hot vinegar solution (from Step 3) over the cucumbers, leaving 1/2 inch headspace. Use a non-metallic utensil to release any trapped air bubbles, then refill with brine as needed to leave 1/4 inch headspace. Wipe the rims clean and seal each jar with a lid and ring according to your canning instructions.

Repeat the assembling process for the remaining jars. Once all jars are filled and sealed, process them in a boiling water bath for 15 minutes to ensure safe preservation. Allow the jars to cool at room temperature. For the best flavor, I recommend letting the pickles sit for at least two weeks before opening a jar.