Onion Amposta Purple
$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, youโll 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 gardenerโs 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 theyโre impractical, but large enough to feel generous when lifted from the soil and set on the kitchen bench. Itโs 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 12โ14 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.
| 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 |
๐ฑ 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: MayโAugust
- Subtropical zones: AprilโJune
- Arid zones: AprilโJuly
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 theyโre a few centimetres tall, or leave a few to snip as microgreens.
๐ผ Tip: Onions are slow starters. Be patientโit may take 10โ14 days for germination.
Direct Sowing
Direct sowing is possible in mild climates with well-prepared, weed-free soil.
- Sow shallowly, 0.5โ1 cm deep.
- Thin seedlings to 10โ15 cm apart as they grow.
- Keep beds moist during germination.
๐ฟ My advice? Go with trays first if youโre dealing with clay soil, slugs, or heavy rain. Youโll get stronger seedlings and better spacing at transplant time.
๐งฑ Soil and Position
Soil Type:
- Onions prefer free-draining, fertile soil with a neutral pH (6.0โ7.0).
- 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).
๐ผ Gardenerโs note: Raised beds or mounded rows are great for drainage, especially in winter-wet areas.
๐ฟ Care and Maintenance
- Watering: Regular and consistentโdonโt let them dry out or become waterlogged. Reduce watering as bulbs mature.
- Weeding: Keep the bed clean. Onions donโt like competition.
- Feeding: Light feedersโapply a liquid seaweed or fish emulsion every 2โ3 weeks early on. Too much nitrogen late in the season can delay bulb formation.
๐ฑ Tip: Mulching with straw or sugarcane mulch keeps weeds down and moisture even.
๐ผ Companion Planting Guide
| Good Companions | Why It Works |
|---|---|
| Carrots | Mutual pest protection (onions deter carrot fly) |
| Beets | Similar soil needs and growth habits |
| Lettuce | Shallow-rooted, fills space between rows |
| Chamomile | Improves onion flavour |
| Strawberries | Onions deter pests like aphids |
๐ซ Avoid planting near: Peas, beans, or other legumesโonions can stunt their growth.
๐พ Harvesting
Green Onions / Spring Onions
- Harvest when leaves are 15โ20 cm tall and stalks pencil-thick.
- Usually ready 8โ10 weeks from sowing.
Pickling Onion
- Timing: Around 10โ12 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 donโt need to flop like storage onions).
Bulbing Onions
- Ready in 20โ26 weeks depending on variety and growing conditions.
- Wait until the tops yellow and fall over naturally. Stop watering at this stage.
- Allow bulbs to โcureโ in a dry, airy spot for 2โ3 weeks before storing.
๐ฟ Harvest tip: Gently lift with a forkโdonโt yank, or you risk bruising them.
๐ Common Issues & Fixes
| Problem | Symptom | Fix |
|---|---|---|
| Poor bulb development | Lots of leaves, no bulb | Too much nitrogen or overcrowdingโthin seedlings & avoid overfeeding late |
| Downy mildew | Pale patches, stunted growth, fuzzy spores on leaves | Improve airflow, avoid overhead watering, use organic fungicide |
| Onion thrips | Silvery streaks, curling leaves | Neem oil spray, encourage lacewings and ladybirds |
| Bolting (flowering early) | Tall central stalk with flower | Sow at the right time, protect from cold snaps |
| Rot or fungal disease | Yellowing, mushy base, or collapsed stems | Ensure well-drained soil, rotate crops, donโt overwater |
๐ผ Seed Saving Guide
Saving onion seed takes patience, but itโs 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.
๐ฟ Lifespan of onion seed: About 1โ2 years with good viability if stored well.
๐ป Final Thoughts
Growing onions from seed might take a bit of patience, but itโs well worth the effort. Starting them off rightโespecially in traysโsets you up for a strong, healthy crop that stores well into the warmer months. Theyโre not heavy feeders, but they do need consistency and care, especially when young. And while theyโre not the flashiest crop, they quietly anchor the garden and the kitchen alike.
So go onโpop 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, youโll have a harvest that smells sweet and earthy, ready to lift and cure with pride. ๐ง ๐
4 reviews for Onion Amposta Purple
| 5 star | 100% | |
| 4 star | 0% | |
| 3 star | 0% | |
| 2 star | 0% | |
| 1 star | 0% |
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 ๐๐ฟ
Delivery Guarantee
We take great care to make sure your seeds arrive safely. If your order is lost or damaged in transit, weโll happily send a replacement. Unfortunately, we canโt 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. Weโre 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. Youโll receive an email once your seeds have been posted, letting you know theyโre on their way. If you donโt see it in your main inbox, please check your Spam or Promotions folders as sometimes our emails like to hide there.












See all our verified customer reviews on our official CusRev profile.
See all our verified customer reviews on our official CusRev profile.
See all our verified customer reviews on our official CusRev profile.
See all our verified customer reviews on our official CusRev profile.