Preserve · field guide
Zucchini Relish
When two zucchini plants bury you in squash, relish is the trick that clears the pile and stocks the pantry. This is a vinegar-based relish, so the acid keeps it safe for water-bath canning. It tastes like the sweet pickle relish you buy, but better, and it uses up the zucchini nobody wants to grill again.
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Why this one works
Zucchini is bland on its own, which is exactly why it makes great relish. It takes on the vinegar, sugar, and spice and turns into a bright, crunchy topping. One large batch clears about 3 pounds of squash and gives you 6 half-pints, roughly a year of relish for most families.
The overnight salt-and-drain is the part people skip, and it is the part that matters. Zucchini is mostly water. Pull that water out first or the relish ends up thin in the jar, and a watery relish is also a more dilute one.
Pick and prep the zucchini
Use young, firm zucchini about 6 to 8 inches long. Big baseball-bat squash works too, but scoop out the seedy center first because it turns mushy. Grate or finely chop the squash along with onion.
Toss the grated zucchini and onion with canning salt, then refrigerate overnight, about 12 hours. Drain it, rinse it once, and squeeze out the liquid by hand. The drier the shred, the thicker the relish and the better it holds up in the jar.
Keep it safe
This relish gets its safety from vinegar, so do not cut the vinegar or swap in a weaker one. Use 5 percent acidity vinegar, the strength on a standard bottle. That acid is what makes it safe to store on a shelf instead of in the fridge.
Cook the relish down for the full time. The long simmer is not just about texture: boiling off water concentrates the acid and is part of the process the times below were validated against.
Leave 1/2 inch of headspace at the top of each jar. Process half-pints and pints for 15 minutes in a boiling-water canner at 0 to 1,000 feet, adding 5 minutes to 6,000 feet and 10 minutes above that. After 12 to 24 hours, check that every jar sealed and the lid does not flex when pressed. Refrigerate any that did not seal and use those first.
How long it keeps
Sealed jars keep their best quality for about 12 months in a cool, dark pantry. Label every jar with the date so you eat the oldest first. Once you open a jar, keep it in the fridge and use it within a month.
One honest note: relish takes real time. The salt-and-drain runs overnight, then the cook-down and the process take the better part of the next afternoon. The payoff is a year of relish from squash you would have otherwise composted.
Recipe
Ingredients
- 10 cups grated zucchini (about 3 lbs)
- 4 cups finely chopped onion
- 5 tbsp canning or pickling salt
- 2 1/2 cups sugar
- 2 1/2 cups 5% white vinegar
- 1 tbsp celery seed
- 1 tbsp mustard seed
- 1 tsp ground turmeric
- 1 red bell pepper, finely chopped (optional, for color)
Method
- Toss grated zucchini and onion with the salt in a large bowl. Cover and refrigerate overnight, about 12 hours.
- Drain, rinse once with cool water, then squeeze out the liquid by hand.
- In a large pot, combine sugar, vinegar, celery seed, mustard seed, and turmeric. Bring to a boil.
- Add the drained zucchini, onion, and bell pepper. Boil gently about 45 minutes, stirring often, until the relish is thick and most of the liquid has cooked off.
- Wash jars and keep them hot. Ladle hot relish into jars, leaving 1/2 inch headspace.
- Wipe rims, set lids and bands finger-tight, and lower jars into the canner.
- Process half-pints or pints 15 minutes at a full rolling boil (0 to 1,000 ft; add 5 minutes to 6,000 ft, 10 minutes above).
- Cool 12 to 24 hours, check every seal, and refrigerate any jar that did not seal.
Keep going
Questions, answered straight
No. The vinegar is what makes this relish safe to store on a shelf. Use 5 percent acidity vinegar and do not cut the amount. If you want it sweeter, add a little more sugar instead.
Yes, and give it the full overnight. Zucchini is mostly water. Skipping or shortening the salt-and-drain leaves a thin, watery relish, and a more dilute one, which works against the acid that keeps it shelf-stable.
Sealed jars keep their best quality for about 12 months in a cool, dark pantry. Label each jar with the date. Once opened, refrigerate and use within a month.
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