Dark Cosmos Collection

The darkest, richest textured and coloured cosmos together in one pack. Enjoy picking hundreds of vases of them from late June until at least October. More
140 seeds 030110 £4.95 In stock
Items will be despatched in 5-7 working days.
10 seedlings 510331-10 £11.50 Delivery mid April
When in stock, please allow up to 2 weeks for delivery.
20 seedlings 510331-20 £18.50 Delivery mid April
When in stock, please allow up to 2 weeks for delivery.
More Details

The darkest, richest textured and coloured cosmos together – plant these direct into a sunny corner of your garden and pick hundreds of vases of them from late June until at least October.

Cosmos are stacked full with nectar and pollen – bees and butterflies love them. They are also very easy to grow, so are perfect for beginners.

The seed packet contains a mix of both varieties whilst the seedling Collection includes 5 or 10 seedlings each of:
Genus Cosmos
Type Half-Hardy Annual
Border Position Middle
Soil Type Chalky, Neutral
Scent Unscented
Site Full Sun
Moisture Moist but Well-drained, Well-drained
Height 75-120cm (30-47in)
Spacing 45cm (18in) apart, 15 seedlings fills 5m² (ie 5m x 1m border, or 2.5m x 2m patch)
Sowing, Seeds, Planting Sow under cover in mid spring and plant out after last frosts, or direct sow early May. Clear area, dig over, rake soil to form a fine seed bed into which seeds will readily germinate. Scatter seeds evenly, rake over and water.
Care Tips Pinch out to promote bushier plants, deadhead regularly. May need some support.
Flowering June - October
Vase Life 7-10 days, no conditioning needed. This is a cut-and-come-again variety.
Harvesting Flower production: 4-5 months.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
  • Sow Under Cover/Plant Indoors
  • Direct Sow/Plant Outdoors
  • Flowers/Harvest
Advice & Videos
How to plant and grow cosmos

Even if you only have a tiny garden – or just some pots – you have to grow at least one cosmos. They are the lowest maintenance,...

Direct sowing seeds

Learn how to get great results when direct sowing hardy annual seeds.


Plant Delivery - When in stock, please allow up to 2 weeks for delivery.

Seeds Delivery - Items will be despatched in 5-7 working days.

Click here to find out more information about our delivery rates and times.

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Dark Cosmos Collection reviews

* * * * - Average based on 4 reviews
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Dark cosmos collection

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Reviewed 18th April 2015 by Fiona jacovides

Disappointed with my seedlings. Some of them looked Very spindly. It remains to be seen how well they will do. I wouldn't have picked these if I had gone to the garden centre I would have gone for healthier looking plants.

Reply from the Sarah Raven Team:

"Hi Fiona, Thank you for your review. We are so sorry to hear that this has happened, but it sounds like they may have been wrapped a bit prematurely and then delayed in the post, causing them to look this way. Please get in contact at info@sarahraven.com or give us a call and we will more than happily arrange for replacement plants to be sent to you."

Posted 23rd April 2015

some seedlings poor quality

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Reviewed 18th April 2015 by Hilary Walton

Had to re-order the Cosmos Antiquity as they arrived in poor condition, quite different from the other two in the collection. The new seedlings have yet to arrive. Am sure they will all give a good show later on!

Reply from the Sarah Raven Team:

"Hi Hilary, we are so sorry to hear that they've arrived this way. We are aware that the Antiquity did not grow on as quickly as the other two varieties, however we are confident that you should have a good display later in the season. If you have any problems with the new ones that are on their way, please do contact us on the phone or via email at info@sarahraven.com and we will do our best to help."

Posted 23rd April 2015

Wonderful long-lasting show

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Reviewed 22nd November 2014 by Red Squirrel

I bought this dark cosmos mix along with the pale cosmos collection and mixed the seeds together. They were planted in a long border along with tall salvias and they have been a wonderful show of colour since mid July and are only now (mid Nov) starting to look shabby. You must continually deadhead though to keep them flowering. I have picked many bunches of them and they look so nice in a pretty little vase.

Still Flowering in October

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Reviewed 16th June 2014 by Brown Owl

Got this set of 15 in June after my own seeds failed to germinate because it was such a cold spring. I'm glad I did as by August I had a wonderful display of cosmos no doubt helped by such a heatwave. With half term coming up l still have lots of cosmos on display its underplanted with some orange Scura dahlias and looks stunning. The Dazzler is my favourite of the three tall, floriforous and bright pink.