Prep the Cucumbers: Wash cucumbers thoroughly. Slice 1/16 inch off the blossom end of each one (this helps prevent softening during fermentation), but leave about 1/4 inch of the stem intact. Place the whole cucumbers into a clean, food-safe 1-gallon container or crock.
Make and Add the First Brine (Day 1): In a saucepan, bring 2 quarts of water and 1/4 cup canning salt to a boil. Pour the hot brine over the cucumbers. Weigh the cucumbers down with a plate or fermentation weight to keep them submerged. Cover the container with a clean kitchen towel and set it in a cool area around 70°F.
Drain and Replace Brine (Days 3 and 5): On the morning of days 3 and 5, pour off the used brine and discard it. Rinse the cucumbers with cool water. Sanitize the weight and container cover by briefly boiling them. Make a fresh brine with 2 quarts of water and 1/4 cup salt, bring it to a boil, and pour it over the cucumbers. Replace the weight and towel cover.
Add Vinegar and Spices (Day 7): On day 7, drain and discard the brine. Rinse cucumbers and sanitize all equipment as before. If you like, slice the cucumbers into spears or chunks. Return them to the container. In a saucepan, combine 4 cups of 5% acidity vinegar and 2 cups of sugar. Place 2 Tbsp pickling spices and 1 Tbsp celery seed in a cheesecloth bag and add to the pot. Bring to a boil, then pour over the cucumbers. Cover with the weight and towel as before.
Sweeten the Syrup (Days 8–13): Each day from days 8 through 13, drain the syrup (keeping the spice bag with it), and add 1/2 cup of sugar to the syrup. Bring it to a boil, then pour it back over the rinsed cucumbers in the sanitized container. Repeat daily, remembering to sanitize the container, weight, and towel each time.
Can the Pickles (Day 14): On the final day, drain the syrup into a saucepan and add a final 1/2 cup of sugar. Bring it to a boil and discard the spice bag. Pack pickles into hot, sterilized pint or quart jars, leaving 1/2 inch headspace. Pour the hot syrup over the pickles, maintaining 1/2 inch headspace.
Process the Jars: Wipe jar rims, apply two-part canning lids, and process jars in a boiling water bath canner for 10 minutes for both pints and quarts, adjusting for altitude if above 1,000 feet in elevation.