Gather the ingredients.
Put the chopped cucumbers, peppers, celery, and onions in a large stainless steel or enamel-lined pot.
Add the pickling salt, stir to combine, and cover. Let stand at room temperature for 4 hours.
Put the canning jars in the water bath canner, cover with water, and bring to a boil. Reduce the heat to low and keep it at a simmer (not boiling).
Put the lids in a saucepan, and bring them to a simmer. Keep them in the hot water until you are ready to use them.
Transfer the vegetables to a large colander, drain, and rinse thoroughly with cold water. Use your hands to squeeze out excess liquid.
Rinse the pot you used for the vegetables. Combine the vinegar, sugar, mustard seeds, and celery seeds in the pot. Bring to a boil over medium-high heat.
Add the drained vegetables and stir to combine. Return to a full boil; reduce heat to medium-low, and simmer for 10 minutes.
Fill prepared jars, leaving ½-inch headspace.
Fit lids on jars and screw bands down to fingertip tightness.
Process in a boiling water bath canner with water at least 1 inch above the jars for 10 minutes. Turn off heat, remove the canner cover, and wait 5 minutes before removing jars.
Once cooled, tighten the lids and store. You can put a jar in the fridge and use right away if you'd like. Enjoy!
