Salt the Cucumbers and Onions: In a very large non-reactive bowl (glass, ceramic, or stainless steel), combine the sliced cucumbers and thinly sliced onions. Sprinkle them with the pickling salt and stir well to combine. Cover the bowl with a damp towel or plastic wrap and let it rest at room temperature for 2 hours. This draws out excess moisture from the vegetables, resulting in a crisper pickle.

Prepare Jars, Lids, and Canner: While the cucumbers and onions are resting, prepare your jars, lids, and canner. Wash all your equipment (jars, rings, jar lifters, funnels, etc.) in hot, soapy water. Rinse thoroughly. Fill your canner with water and bring it to a boil, carefully placing your jars inside. Boil the jars for 5-10 minutes to sterilize them. Remove the canner from the heat and set it aside until you’re ready to fill the jars. Add the canning lids to a small saucepan filled with water and bring to a low simmer. Keep the lids warm until needed.

Rinse and Drain: After 2 hours, transfer the cucumber and onion mixture to a colander placed over the sink. Rinse thoroughly with cool running water to remove the excess salt. Drain well.

Prepare the Brine: In a large stainless steel or non-reactive saucepan (at least 16 cups/4 quarts), combine the vinegar, sugar, mustard seeds, celery seeds, and turmeric. Whisk the ingredients together and bring to a boil over medium-high heat, stirring often to dissolve the sugar.

Add Vegetables to Brine: Once the brine has come to a boil, stir in the drained cucumbers and onions. Return the mixture to a boil.

Pack Jars: Remove the sterilized jars from the hot water in the canner, carefully emptying any water back into the canner. Pack the hot vegetables into the hot jars, leaving a generous ½ inch of headspace at the top of each jar.

Add Brine and Remove Air Bubbles: Ladle the hot liquid brine over the vegetables in each jar, covering them completely while maintaining the ½ inch headspace. Use a butter knife or de-bubbler to remove any air bubbles trapped in the jars. Add more liquid if needed to maintain the proper headspace.

Wipe Rims and Apply Lids and Rings: Wipe the rims of the jars with a clean, damp towel or paper towel to remove any residue. Place a warm lid on each jar. Secure each jar with a canning ring, tightening it until it’s fingertip tight (tighten with your fingertips, stopping when you feel resistance).

Process Jars: Place the filled jars back into the canner, ensuring they are covered by at least 2 inches of water. If the water level is not high enough, add more hot water (I like to keep a kettle handy for this). Add the lid to the canner and bring the water to a rolling boil.

Process Time: Once the canner has returned to a rapid boil, start the processing time. Keep the lid in place and allow the jars to process for 10 minutes.

Cool and Seal: After 10 minutes, turn off the heat and remove the canner from the heat source. Remove the lid and let the jars rest in the canner for 5 minutes.

Remove Jars and Check Seals: After 5 minutes, carefully remove the jars from the canner using a jar lifter and place them on a towel-lined surface in a location where they can remain undisturbed for at least 24 hours. As the jars seal, you should hear a “pop” sound. Allow up to 24 hours for each jar to seal, but most will seal within the first few hours.

Check Seals, Label, and Store: After 24 hours, check the seals by pressing down on the center of each lid. If the lid doesn’t flex, it’s sealed properly. Remove the canning rings. Wipe down the jars and label them with the contents and date. Store any sealed jars in a cool, dark, dry place. Any jars that did not seal should be moved to the refrigerator and eaten right away.

Wait Before Enjoying: I recommend waiting for 1-3 weeks before opening and enjoying your pickles. This allows the flavors to fully develop and meld together.