Zucchini relish
Bernardin’s hot-dog relish for the zucchini that got away — a touch of horseradish and one hot pepper give it its bite.
Makes
About 6 × 500 ml (pint) jars
Active time
1½ hours over two days
Total
Overnight salting plus 2½ hours, then 24 hours cooling
Before you start
What keeps this jar safe
- Zucchini, onion and peppers are all low-acid; the 625 ml of 5% vinegar for these measured cups of vegetable is what makes the relish a boiling-water job. Measure the chopped vegetables, do not guess by weight alone.
- Salt overnight, rinse and wring — the salting pulls water out so the vinegar is not diluted in the pot.
- Boil it down until thick (about 45 minutes); a watery relish was not what was tested and separates in the jar.
- No cornstarch or flour to thicken, and no extra vegetables. The horseradish is prepared (vinegar-packed) horseradish, not fresh grated root.
This follows Bernardin: Zucchini Relish. Quantities, acid and times are theirs; do not scale the vegetables without scaling everything, and do not change the vinegar, lemon juice or processing time.
Ingredients
- 2 kg (4¼ lb) zucchini, about 14 medium — finely chopped to measure 3 L (12 cups)
- 675 g (1½ lb) onion, about 5 medium — finely chopped to measure 1 L (4 cups)
- 2 large sweet red peppers
- 1 large sweet green pepper
- 75 ml (⅓ cup) pickling salt
- 625 ml (2½ cups) granulated sugar
- 15 ml (1 tablespoon) each ground nutmeg and ground turmeric
- 625 ml (2½ cups) white vinegar (5%)
- 60 ml (4 tablespoons) prepared horseradish
- 1 large hot pepper, seeds and all, chopped
Processing
- Jars
- 500 ml (pint)
- Headspace
- 1 cm (½ inch)
- Time at 0–300 m (0–1,000 ft)
- 15 min
- Higher up
- Bernardin’s chart: add 5 min at 306–915 m (1,001–3,000 ft), 10 min at 916–1,830 m (3,001–6,000 ft), 15 min at 1,831–2,440 m (6,001–8,000 ft), 20 min at 2,441–3,050 m (8,001–10,000 ft).
Method
- 1
The day before: pulse the zucchini in a food processor until finely chopped and measure 12 cups; do the same with the onions and measure 4 cups. Seed the sweet peppers, finely chop the green one and cut the red ones into 6 mm (¼ inch) cubes. Toss everything in a large glass or stainless bowl with the pickling salt, cover and refrigerate overnight.
- 2
Next day, tip the vegetables into a colander, rinse under cold running water, then line the colander with cheesecloth and twist the bundle hard to wring out as much water as you can — a satisfying job for strong small hands.
- 3
Put the vegetables in a large stainless steel pot with the sugar, nutmeg, turmeric, vinegar, horseradish and hot pepper. Bring to a boil, then lower the heat and boil gently, stirring often, until thick — about 45 minutes.
- 4
Meanwhile set 6 washed 500 ml jars on the rack in the canner, cover with water and heat to a simmer (82 °C / 180 °F). Wash the lids in hot soapy water and set them aside with the bands.
- 5
Ladle the hot relish into a hot jar to within 1 cm (½ inch) of the rim. Slide a plastic knife or chopstick around the inside to free bubbles, wipe the rim clean of any stickiness, centre the lid and screw the band down to fingertip-tight. Put the jar back in the canner and repeat.
- 6
With the jars covered by water, put the lid on the canner and bring it to a full boil. Process 15 minutes at 0–300 m.
- 7
Turn off the heat, lift the jars out without tilting and cool them upright, undisturbed, 24 hours. Do not retighten the bands. Check that every lid curves down; refrigerate any that did not seal.
Keeps: 12–18 months in a cool dark cupboard. Refrigerate after opening and use within a month or two.
Variations: Leave out the hot pepper for a mild relish children will eat on everything — the vinegar ratio does not change. Nutmeg is the flavour people either love or leave out; it can be dropped.
Tested source: Bernardin: Zucchini Relish. Checked October 2026. If a jar did not seal, refrigerate it and use it within a few days. Never taste anything from a jar that is bulging, leaking, spurting or smells wrong — when in doubt, throw it out without tasting.
The crop
Zucchini: when to pick, how to store, what else to make →
Grate it and freeze it: young zucchini grated, steam-blanched 1–2 minutes until translucent, packed in measured 250 ml or 500 ml amounts and frozen, is the glut solved — each bag is a loaf of bread or a batch of fritters in winter, once you pour off the water that comes out on thawing. Slices blanched 3 minutes freeze too, but they come back soft and are for soup. Relish and pickles are the other answer: summer squash relish and bread-and-butter zucchini pickles are tested water-bath recipes with 5% vinegar. What does not work — and this surprises people every year — is canning plain zucchini or summer squash, in cubes or slices, in water or broth. The canning authorities withdrew those instructions decades ago because the squash packs down and heats unpredictably, and ‘canning summer squash without pickling is not recommended’ is the current rule. The only ways zucchini goes in a jar are a tested pickle or relish, or as a minor ingredient in a tested pressure-canned mixed-vegetable or tomato recipe.
More for zucchini
- Pickling
Bread-and-butter pickles
Sweet, turmeric-yellow cucumber and onion slices — the pickle most children will actually eat, and the one that uses up the big cucumbers.
About 8 × 500 ml (pint) jars · 1¼ hours active
The recipe →