40 seeds 030107 £2.25 In stock
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When in stock, please allow up to 5 working days for despatch.
5 seedlings 510702-5 £6.50 Delivery mid April
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When in stock, please allow up to 4-6 weeks for despatch. 
10 seedlings 510702-10 £11.95 Delivery mid April
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When in stock, please allow up to 4-6 weeks for despatch. 

Or buy this as part of our Bestseller Cosmos and Zinnia Collection and Dark Cosmos Collection.

More Details

An even darker, richer and more luscious colour than 'Antiquity' or 'Dazzler', and a short one too, so in a sheltered spot should not need staking. My current favourite.

Genus Cosmos
Group/Species bipinnatus
Variety Rubenza
Type Half-Hardy Annual
Common Name Cosmos
Border Position Cutting Garden
Soil Type Broad Tolerance
Scent Unscented
Site Full Sun
Moisture Moist but Well-drained
Height 60cm (24in)
Spacing 45cm (18in)
Sowing, Seeds, Planting Sow under cover in mid spring and plant out after last frosts, or direct sow early May. Grow seedlings on in individual pots or modules until large enough to plant out. Gradually acclimatise to outdoor conditions for 7-10 days before transplanting into the garden after all risk of frost has passed.
Care Tips Pinch out tips at 15-20cm to encourage bushier plants. Stake and tie Cosmos plants if necessary during the growing season, water regularly and dead-head to prolong the flowering season.
Flowering July - October
Vase Life 7-10 days, no conditioning needed. Pick fresh straight into water, just as the buds are about to bloom, and do not pick in the heat of the day. Deadhead the main blooms that are drooping and going over after about a week. Place out of direct sunlight.
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
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Delivery

Plant Delivery - When in stock, please allow up to 4-6 weeks for despatch. 

Seeds Delivery - When in stock, please allow up to 5 working days for despatch.

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

Cosmos bipinnatus 'Rubenza' reviews

* * * * * Average based on 34 reviews

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Reviewed 21st April 2020 by Mrs Parker

perfect for the reason i ordered them

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Reviewed 16th August 2019 by Anita

Previous comments about this not really being red but more pink have turned out to be unjustified. These are the most gorgeous ruby red. I love them! They last really well in a vase too.

* * * * *

Reviewed 13th August 2019 by Christine

Good germination. Lovely flower.
Both these Cosmos have been successful multiple times, but I don't seem to have luck at all with Purity.

* * * * -

Reviewed 8th August 2019 by Barbara

Very pretty, and flowered quite well.

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Reviewed 1st August 2019 by Anita

Previous comments about this not really being red but more pink have turned out to be unjustified. These are the most gorgeous ruby red. I love them! They last really well in a vase too.

* * * * *

Reviewed 1st August 2019 by Gill

The plants were healthy on arrival and grew well

* * * * *

Reviewed 31st July 2019 by James

Brilliant, flowering prolifically

* * - - -

Reviewed 31st July 2019 by Dr Yeates

the plans have grown very small unlike last year.

* * * * *

Reviewed 31st July 2019 by Lorna

Much better quality seedlings this time - they replaced seedlings that had either died or looked as if they were about to! All replacement plants thrived and are looking beautiful.

* * * * -

Reviewed 31st July 2019 by Sarah

The plants are excellent quality and flowering well. I do worry amount of packaging needed to send them by post

* * * * *

Reviewed 31st July 2019 by Jessica

Easy to grow and a great colour.

* * - - -

Reviewed 31st July 2019 by Patricia

Excellent service - plants have not done as well as hoped in this very hot summer.

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Reviewed 31st July 2019 by Lesley

Took quite some time to get established and start to flourish. Still no flowers yet.

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Reviewed 31st July 2019 by David

Everything arrived on time

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Reviewed 31st July 2019 by Marion

* * * * *

Reviewed 31st July 2019 by Christine

Good germination. Lovely flower.
Both these Cosmos have been successful multiple times, but I don't seem to have luck at all with Purity.

* * * * *

Reviewed 31st July 2019 by Mary

* * - - -

Reviewed 24th November 2018 by Betty

The plants were fine but the colour was disappointing

* * * * -

Reviewed 13th November 2018 by C Payne-Johnson

OK earlier iin summer. Died down in autumn

* * * * -

Reviewed 9th November 2018 by Susan

Some where better than others, but having said that some are still flowering so that's not bad.

* * * * *

Reviewed 7th November 2018 by Anita

Fabulous growth and flowers

* * * * -

Reviewed 31st October 2018 by Carolyn

Very healthy seedlings which grew well once potted on. The flowers were lovely but sadly the slugs have enjoyed them too.

* * - - -

Reviewed 4th October 2018 by Poppy

2 seedlings dead on arrival

Reply from the Sarah Raven Team:

"Thank you for leaving your review. We are very sorry to hear of your disappointment with your Cosmos Seedlings and have refunded you for them."

Posted 7th November 2018

* * - - -

Reviewed 19th September 2018 by Sarah

Service is great from Sarah Raven and the emails and information are brilliant. As a result I bought a lot in 2018. I know the weather was v difficult but I am really disappointed by results from the Sarah Raven plants.

Reply from the Sarah Raven Team:

"Thank you for leaving your review. We are very sorry to hear of your disappointment with your Cosmos seedlings and have refunded you for them."

Posted 7th November 2018

* * * * *

Reviewed 14th September 2018 by Sue

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Reviewed 13th September 2018 by VANESSA

WOW! These seedlings are now giants and still flourishing bringing great height and colour to my teeny / weeny city garden.
The butterflies love them and the bees have been hovering these last few days.
I planted them in various sized pots I didn't realise they would need staking, the stems are now like trunks.
I'll definitely order them again next year.

* * * * -

Reviewed 12th September 2018 by ANN

That I've rated them 4 stars means that I as cultivator was lacking a certain skill!

* * * * *

Reviewed 8th September 2018 by Margaret

These, plus all the other cosmos I bought have been amazing. Still loads of flowers still to come. A real show stopper. Will be re ordering next year

* * * * -

Reviewed 6th September 2018 by Helene

Please see the comment left for "Cranberry click".

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Reviewed 3rd September 2018 by Lesley

Like these very much as planted with roses and blended well, not as tall and large flowered as others but lovely colour

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Reviewed 29th August 2018 by Michael

Another great favourite. I love the velvet red and yellow centre

New seedlings

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Reviewed 10th April 2018 by Ann

A gift from my daughter, 10 seedlings of Rubenza and 10 of Dazzler in beautiful condition, very strong. I am looking forward to seeing them grow.

Stunning

* * * * *

Reviewed 19th June 2015 by Chris Page

A beautiful ruby red cosmos, which fade to a pale terracotta red. So the combination of flower colour on one plant is stunning. One I plan to grow again.

Champion of the clarets!

* * * * *

Reviewed 8th October 2014 by Arthur Parkinson

Not only does this annual have one of the most sumptuous titles but it's also a worthy choice as a summer bloomer. Shorter than others so not needing to normally be staked this more dainty cosmos gives just as much punch with it's deep claret petals and honey yellow Center. I love it paired with cerinthe major.

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