Thompson & Morgan

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Onion 'Santero' F1 Hybrid (Spring Planting)

Allium cepa

Hardy Bulb

  • Introduced by T&M
  • Customer Favourite

Spring planting. Heat treated.

The answer to gardeners' prayers! Heat treated early main crop, Onion 'Santero' F1 Hybrid is the first onion set with resistance to downy mildew, a potentially disastrous fungal foliage disease. This 'Rijnsburger' type onion produces copper brown, oval-to-round bulbs with medium skin thickness. Yields are similar in quality and quantity to other F1 maincrop varieties currently available, and bulbs have great storage potential. Height: 45cm (18"). Spread: 15cm (6").

Companion planting: Try growing onions with mint to confuse and deter onion fly.

Useful links:

Companion Planting

Pack size info: 375g equates to approximately 75 onion sets.

Ideal For:
kitchen garden
Flowering Period:
June, July
full sun
    • 375g of onion sets

    • Despatch:
    • £5.99
    • Out of stock
    • 750g of onion sets

    • Despatch:
    • £8.99
    • Out of stock

Plant onions in rows in any firm, well drained soil in full sun. Prepare the planting area several weeks in advance by incorporating some well rotted garden compost to improve drainage and soil fertility. Avoid planting onions on freshly manured soil. On particularly wet ground, try growing onions in raised beds.

When growing onions from sets, plant the bulbs so that the tip of bulb is just protruding through the soil surface. Onion plants should be grown on to at least 15cm (6") tall before being gradually acclimatised to outdoor conditions prior to planting outdoors. Leave a space of 10cm (4") between each onion, and 30cm (12") between each row. Cover with a protective netting or fleece to prevent attack from birds and insects. Water the onion plants thoroughly after planting.

Onions are undemanding and require only occasional watering during particularly dry periods. However, rows should be weeded regularly. Harvest onions in late June and July, a week or two after the leaves begin to turn yellow. Choose a dry day to loosen them from the ground with a fork. Leave them on the soil surface for a day or two until they have fully dried in the sun. Once dry, remove the top foliage and store them in a well ventilated, dry position. Bulbs can be stored for several months.

Seeds and garden supplies will normally be delivered within the time period stated against each product as detailed above. Plants, bulbs, corms, tubers, shrubs, trees, potatoes etc are delivered at the appropriate time for planting and will be stated on the product page or in your order acknowledgement page and email.

Orders for packets of seed incur a P&P charge of £1.95.
Orders which include any other products will incur a P&P charge of £4.95.
Where an order includes both packets of seeds and other products a maximum P&P charge of £6.90 will apply - regardless of the number of items ordered.

Please see our Delivery / P&P page for further details and details of any surcharges that may apply to certain destinations.

For product weight information regarding how we despatch our quantities of potatoes, onions and garlic, please see the table below. Exact weights will depend on the individual variety, as well as the weather and growing conditions experienced by the grower.

  1. Santero Onions - Blight Free

    By Steve Southwell 03-09-2014

    This is the third season I have grown Santero on my allotment. They have always produced very good onions of reasonable size and quality. However, this year I was delighted to be the only plot holder to have any onions in the ground in July/August due to particularly bad downy mildew. Fortunately all my fellow "allotmenteers" managed to crop their onion but they were smaller and may not store so well. Next year, all 21 plot holders have decided to purchase Santero to ensure a good quality crop. Thanks T&M for making my plot the talk of the site!


    Thank you for your review. I hope we can continue to be of service.

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