Thompson & Morgan
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Onion 'Rosanna' (Spring Planting)

Allium cepa

Hardy Perennial

 Customer Rating

A distinctive and appealing reddish brown skinned, semi-globe shaped bulb with stunning pink rings when sliced. Onion 'Rosanna' is ideal for all culinary uses with a real old fashioned flavour, similar to those purchased from the French onion seller of yesteryear. Height: 45cm (18"). Spread: 15cm (6").

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

Useful links:

Companion Planting

Ideal For:
kitchen garden
Sowing Months:
March, April
full sun
    • 1 packet (350 onion seeds)

    • Despatch: by Monday
    • £2.19 £0.99

Direct sow onions outdoors in spring on any firm, well drained soil in full sun. Sow thinly at a depth of 1cm (½") and a distance of 30cm (12") between rows. 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 large enough to handle, thin onion seedlings to 10cm (4") apart for medium sized bulbs, or at a slightly wider spacing if larger bulbs are required.

Alternatively sow onion seed indoors in module trays at a depth of 1cm (½"), using free-draining, seed sowing compost. Place in a propagator or seal container inside a plastic bag at a temperature of 10-15C (50-59F) until after germination which usually takes 10-14 days. Once germinated, grow onions on in cool conditions until all risk of frost has passed and they are large enough to plant outdoors at a distance of 10cm (4") apart. Cover with a protective netting or fleece to prevent attack from birds and insects. Water the plants thoroughly after planting.

Onions are undemanding and require only occasional watering during particularly dry periods. However, rows should be weeded regularly. Harvest onions from July onwards, 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.

Despatch: Within 24 hours applies to orders placed online from Sunday to Thursday. Orders placed online on Friday or Saturday will be despatched on Monday. Please note that for Bank Holiday weekends, orders placed Friday to Sunday will be despatched on Tuesday.

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.

  1. Onion Rosanna

    By Denise Cook 24-12-2011

    This is a superb onion. Ive grown this from seed for the last three years, and it survived last year's drought extremely well. It produces aromatic and delicious mauve tinged onions. I would like sets, but this germinates reliably and grows well from seed. If there was only one onion that I could grow, it would be this beautiful and tasty onion. I shall continue to grow and enjoy eating Rosanna for as long as Thompson and Morgan will sell the seed.

  2. onion rosanna

    By Brian Rainford 21-09-2010

    I grew this from sets in 2009 and was very impressed. The bulbs were of medium size, very attractive appearance and stored very well. Excellent flavour. I was disappointed that sets were not avaiilable for 2010 or 2011, but at least the seed is now available. Well worth a try.

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