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Onion Amposta Purple

(4 customer reviews)

$4.95

Allium Cepa

  • Seed Count 75
  • Intermediate Day Variety
  • Annual

In stock

Description

Onion Amposta Purple is cultivated and cherished for its size, colour, and sweetness. Unlike ordinary onions that can sometimes lean too sharp or too bland, this variety finds a perfect middle ground. Its red-purple skins are strikingly attractive, and when sliced open, the colour carries through in rich tones that look as good on the plate as they taste in the mouth.

It has a natural mildness that softens the pungency usually associated with onions. Bite into a slice raw, and instead of a harsh burn, youโ€™ll find a pleasant balance that is sweet and juicy, with just enough of a gentle tang to keep things interesting. Slow-cooked in a pan, its sugars caramelise beautifully, turning into golden strands with a rich, mellow taste that gives depth to any dish. The sweetness develops further with heat, while the dense flesh holds together, meaning it cooks evenly without collapsing into mush.

From a gardenerโ€™s perspective. it has a reputation for being adaptable, reliably growing in a wide range of conditions, and producing strong, vigorous plants. The stems are tall and robust, feeding into bulbs that regularly weigh between 200 and 250 grams each. These are onions of substance: not so huge that theyโ€™re impractical, but large enough to feel generous when lifted from the soil and set on the kitchen bench. Itโ€™s a variety that offers both satisfaction in the garden and abundance in the pantry.

Being an intermediate-day onion, Amposta Purple thrives where the daylight stretches to 12โ€“14 hours a day. In Australian conditions, this makes it well-suited to temperate areas, where it can be sown in late autumn and grown on into the following season. Gardeners in these regions can count on it as a steady producer, one that fits into the rhythm of the year without demanding extremes of weather or soil. Another feature that makes Amposta Purple stand out is its storage ability.

Find your Climate Zone

Method: Raise seedlings
Soil Temp: 8ยฐC - 30ยฐC
Cool Mountain: May - Jul
Position: Full sun
Arid: May - Aug
Row Spacing: 10cm apart
Temperate: April - Aug
Planting Depth: 5mm
Sub Tropical: Apr - Jun
Harvest: 200 days
Tropical: Jun - Jul
Plant Height: 25cm

๐ŸŒฑ Sowing: In Trays vs. Direct in the Garden

In Trays (Recommended for most regions)

Starting onions in trays gives you a head start and allows for better control over spacing later on.
Best time to sow:

  • Temperate & Cool zones: Mayโ€“August
  • Subtropical zones: Aprilโ€“June
  • Arid zones: Aprilโ€“July

How to sow:

  • Use a quality seed-raising mix.
  • Sow seeds 2mm deep.
  • Keep trays in a sunny, sheltered spot or greenhouse.
  • Thin seedlings once theyโ€™re a few centimetres tall, or leave a few to snip as microgreens.

๐ŸŒผ Tip: Onions are slow starters. Be patientโ€”it may take 10โ€“14 days for germination.

Direct Sowing

Direct sowing is possible in mild climates with well-prepared, weed-free soil.

  • Sow shallowly, 0.5โ€“1 cm deep.
  • Thin seedlings to 10โ€“15 cm apart as they grow.
  • Keep beds moist during germination.

๐ŸŒฟ My advice? Go with trays first if youโ€™re dealing with clay soil, slugs, or heavy rain. Youโ€™ll get stronger seedlings and better spacing at transplant time.


๐Ÿงฑ Soil and Position

Soil Type:

  • Onions prefer free-draining, fertile soil with a neutral pH (6.0โ€“7.0).
  • Add well-rotted compost or aged manure a few weeks before planting.

Position:

  • Full sun is essential for strong bulb development.
  • Avoid beds that have recently grown garlic, shallots, or leeks (allium rotation is important to reduce disease risk).

๐ŸŒผ Gardenerโ€™s note: Raised beds or mounded rows are great for drainage, especially in winter-wet areas.


๐ŸŒฟ Care and Maintenance

  • Watering: Regular and consistentโ€”donโ€™t let them dry out or become waterlogged. Reduce watering as bulbs mature.
  • Weeding: Keep the bed clean. Onions donโ€™t like competition.
  • Feeding: Light feedersโ€”apply a liquid seaweed or fish emulsion every 2โ€“3 weeks early on. Too much nitrogen late in the season can delay bulb formation.

๐ŸŒฑ Tip: Mulching with straw or sugarcane mulch keeps weeds down and moisture even.


๐ŸŒผ Companion Planting Guide

Good CompanionsWhy It Works
CarrotsMutual pest protection (onions deter carrot fly)
BeetsSimilar soil needs and growth habits
LettuceShallow-rooted, fills space between rows
ChamomileImproves onion flavour
StrawberriesOnions deter pests like aphids

๐Ÿšซ Avoid planting near: Peas, beans, or other legumesโ€”onions can stunt their growth.


๐ŸŒพ Harvesting

Green Onions / Spring Onions

  • Harvest when leaves are 15โ€“20 cm tall and stalks pencil-thick.
  • Usually ready 8โ€“10 weeks from sowing.

Pickling Onion

  • Timing: Around 10โ€“12 weeks after sowing, depending on variety and conditions.
  • Look for bulbs that are starting to swell but are still small and firm.
  • Leaves will still be upright and green (they donโ€™t need to flop like storage onions).

Bulbing Onions

  • Ready in 20โ€“26 weeks depending on variety and growing conditions.
  • Wait until the tops yellow and fall over naturally. Stop watering at this stage.
  • Allow bulbs to โ€œcureโ€ in a dry, airy spot for 2โ€“3 weeks before storing.

๐ŸŒฟ Harvest tip: Gently lift with a forkโ€”donโ€™t yank, or you risk bruising them.


๐Ÿ› Common Issues & Fixes

ProblemSymptomFix
Poor bulb developmentLots of leaves, no bulbToo much nitrogen or overcrowdingโ€”thin seedlings & avoid overfeeding late
Downy mildewPale patches, stunted growth, fuzzy spores on leavesImprove airflow, avoid overhead watering, use organic fungicide
Onion thripsSilvery streaks, curling leavesNeem oil spray, encourage lacewings and ladybirds
Bolting (flowering early)Tall central stalk with flowerSow at the right time, protect from cold snaps
Rot or fungal diseaseYellowing, mushy base, or collapsed stemsEnsure well-drained soil, rotate crops, donโ€™t overwater

๐ŸŒผ Seed Saving Guide

Saving onion seed takes patience, but itโ€™s very doable if you let your plants go full cycle.

1. Biennial nature:

  • Onions need two seasons to set seed. In the first year, they grow bulbs; in the second, they flower.

2. Selecting parent plants:

  • Choose the healthiest, most typical bulbs (good shape, no disease, strong storage quality).
  • Allow them to cure and store over summer.

3. Replanting:

  • In autumn or early winter, replant the bulbs in prepared soil.
  • The plant will flower in spring, forming beautiful umbel heads full of seeds.

4. Pollination:

  • Onions are insect-pollinated and can cross with other onion varieties.
  • To maintain a pure variety, only grow one type for seed or space them 1 km apart.

5. Harvesting seed:

  • Wait until the flower heads turn brown and dry.
  • Snip off the heads into a paper bag and dry further indoors.
  • Rub heads to release seeds, winnow out chaff, and store in a cool, dry place.

๐ŸŒฟ Lifespan of onion seed: About 1โ€“2 years with good viability if stored well.


๐ŸŒป Final Thoughts

Growing onions from seed might take a bit of patience, but itโ€™s well worth the effort. Starting them off rightโ€”especially in traysโ€”sets you up for a strong, healthy crop that stores well into the warmer months. Theyโ€™re not heavy feeders, but they do need consistency and care, especially when young. And while theyโ€™re not the flashiest crop, they quietly anchor the garden and the kitchen alike.

So go onโ€”pop a few trays in this season, keep an eye on spacing and weeds, and let your onions quietly do their thing. Before you know it, youโ€™ll have a harvest that smells sweet and earthy, ready to lift and cure with pride. ๐Ÿง…๐Ÿ’š

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Postage Charge

Orders under $35 attract a $4.95 shipping charge. Orders $35 and above have free shipping.

Order Times

Seed orders are normally dispatched within three business days. You will receive an email when seeds are mailed out.

Postage Days

Seeds are mailed out Tuesday to Friday at 1pm. Except for the Friday of long weekends.

Postage Times

WA 2-3 Days: SA,NT 3-5 Days: NSW, ACT, QLD, VIC: 5-7 Days

Carrier

We use Australia Post Letter Postage for the majority of orders


Not only are our seeds packed in recycled paper envelopes, we keep the theme going when we post out website orders. To protect your seeds from moisture and the letter box munchers (snails), we use a very special plastic free material made from plants. They are then put into recycled mailing envelopes. Green all the way ๐Ÿ’š๐ŸŒฟ


Delivery Guarantee

We take great care to make sure your seeds arrive safely. If your order is lost or damaged in transit, weโ€™ll happily send a replacement. Unfortunately, we canโ€™t replace or refund orders that arrive later than the estimated delivery date, as delays can sometimes occur that are outside our control.

Please note that all dispatch and delivery times listed are estimates only. While we do our best to post promptly, delivery timeframes can vary due to postal service delays, weather events, or other unforeseen circumstances. Weโ€™re unable to take responsibility for any loss, damage, or cost that results from a late delivery.

An order is not considered missing until at least 20 business days have passed from the postage date. Youโ€™ll receive an email once your seeds have been posted, letting you know theyโ€™re on their way. If you donโ€™t see it in your main inbox, please check your Spam or Promotions folders as sometimes our emails like to hide there.

Onion Amposta PurpleOnion Amposta Purple
$4.95

In stock