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December 13th 2019

Crazy for Cosmos

Written by
Floret

Of all the annual flowering plants you can grow in your cutting garden (or even in the back of your veggie patch), none is more productive than cosmos. They truly are a cut-and-come-again flower: The more you harvest them, the more they bloom.

A single planting will produce buckets of airy, delicate, daisy-like blossoms for many months. You can arrange them on their own or weave them into mixed bouquets. The possibilities are endless.

Field of CosmosCosmos are incredibly easy to grow, making them perfect for beginning gardeners. Seeds can be started indoors to get a jump-start on the season or sown directly into garden beds once the weather warms.

Either way, cosmos will bloom in just under 3 months from the date you sow them.

Close up of Cosmos flowersTo start indoors, sow seeds 4 to 6 weeks before the last spring frost, then plant seedlings into the garden once all danger of frost has passed. Be careful not to sow seed too early, because seedlings will quickly outgrow their pots before the weather has warmed enough to put them out into the garden.

Alternatively, you can sprinkle seeds in your garden once danger of frost has passed. In about a week, you’ll see seedlings sprout up from the soil. Keep the young plants protected from slugs and snails as they are getting established since new growth is quite tender.

Field of cosmos at Floret Flower FarmPlants get very bushy and prefer a little extra room to spread out, so space plants 12 to 18 in (30 to 46 cm) apart. Once in the ground, cosmos will grow rapidly, so be sure to stake them early, while they are still young. Cosmos also benefit from a technique called pinching, which will encourage the already highly productive plants to branch even more vigorously.

Here’s how it’s done: When plants are young, between 8 to 12 in (20 to 30 cm) tall, take sharp pruners and snip the top 3 to 4 in (8 to 10 cm) off the plant, just above a set of leaves. This signals the plant to send up multiple stems from below where the cut was made, resulting in more abundant flower production as well as longer stem length.

I typically do two sowings of cosmos, a month apart. This gives me a wide range of flower types and loads of blooms for cutting from summer into fall. I list some of my favorites here.

 cosmos at Floret Flower FarmThe ‘Double Click’ series is available as a mix or in single colors. This unique double-flowered variety is loaded with fluffy blooms that look great in bouquets.

The Double Click Mix (pictured above) includes snow white, vibrant cranberry, rosy mauve, and a lovely soft blush.

Individual colors are also available, and I am particularly fond of ‘Bicolor Rose’, ‘Cranberries’, and ‘Snow Puff’.

armload of white cosmos at FloretNothing says country charm like pure white cosmos, and two of my favorite white varieties are ‘Purity’ and ‘Psyche White’.

Purity’ (pictured above, left) is a cheerful daisy-like bloomer that produces an abundance of pure white, single flowers.

The large, pure-white blooms of ‘Psyche White’ (pictured above, right) are a mixture of single and semi-double flowers with a central ring of fluffy miniature petals. The ruffled flowers look like snowflakes dancing in the breeze.

armload of blush cosmos at FloretTwo recent introductions to the cosmos family remind me of the Sugar Plum Fairy.

The pale blush petals of ‘Cupcakes Blush’ (pictured above) are fused together, forming a teacup-shaped flower. Blooms are as big as the palm of your hand, and the edges look as if they have been cut with pinking shears. This romantic variety is a mix of single, semi-double, streaked, and solid flowers. Perfect for wedding work, this variety is a must-grow!

Cupcakes White’ is a pure-white version of its blush sister. Flowers are just as big and are extremely versatile for arranging.

harvesting cosmos at Floret Flower FarmIf you’re drawn to rich, dramatic colors, look no further than these stunning beauties.

Rubenza’ (pictured above, left) is an uncommon cosmos in a vibrant range of colors. The large, single blooms open with deep ruby petals and then fade into shades of muddy rose and terracotta as they age. There is nothing like this variety.

Velouette’ (pictured above, right) has fast become a new favorite on the farm and features deep mahogany flowers with delicate white striping. Tall and dramatic, this variety churns out armloads of long stems that are perfect for bouquets.

Xanthos and Pink Lemonade Cosmos from FloretTwo fun novelty cosmos carry the most unusual colors. While both are on the shorter side, they make up for it in their exquisite coloring.

The delicate, pale yellow flowers of ‘Xanthos’ (pictured above, left) have green undertones. The unique ruffled flowers have a subtle inner collar and pale throat, and blossoms have a dark yellow eye encircled by tiny fringed petals with pale, serrated tips.

There is absolutely no cosmos like the beautiful ‘Apricot Lemonade’. The unique color reminds us of ‘Distant Drums’ roses—watercolor petals start out a soft apricot with a dusty lavender reverse and fade to a buttery yellow. Variations among the blooms include some flowers with a mauve ring at the throat. A bit of separation between the petals gives the impression of a pinwheel with snipped dovetail edges. This is a must-grow for event work.

Armload of cosmos at FloretStriking in both the garden and the vase, these fun and eye-catching varieties are a must-grow if you’re looking for something different.

The palest pink blooms with dark rosy throats make ‘Daydream’ (pictured above, left) an eye-catching addition to the landscape and a sweet treasure for the cutting garden or flower border. This variety has proven to be the most heat-tolerant cosmos we’ve grown.

Xsenia (pictured above, right) is an early-to-flower gem that is a new favorite on the farm. Shades of magenta, purple, and raspberry have an iridescent quality and age to an apricot cast. Blooms are more petite than those of other cosmos varieties, and medium-size, healthy plants carry flowers on strong, upright stems. Because the bloom color is so varied, the flowers have a chameleon-like quality, and they mix well with a wide range of shades.

Armload of cosmos flowers at Floret Flower Farm Finally, we have to mention two beautiful and hardworking pink treasures.

The delightful Seashells Mix (pictured above, left) is filled with large, showy blooms that have fluted, tubular petals resembling seashells. Flowers come in a sweet pastel mix of pink, rose, white, carmine, and other unique bicolors.

Rosetta’ (pictured above, right) is a new variety that’s a must-have for arranging and looks stunning en masse. Blooms have a layer of half-double petals that resemble fluffy petticoats. This variety is a mix of soft pink, blush, and rose; each petal looks hand-painted.

pollinators and cosmos at Floret Flower Farm To prolong their flowering time, keep cosmos harvested regularly, and deadhead any spent flowers before they set seed. The individual blooms of cosmos don’t last a particularly long time in the vase, about 5 to 6 days, but each stem is loaded with multiple blossoms that open individually over a period of a week.

Harvest when the buds are colored but haven’t opened up yet; this will keep insects from pollinating them and help stretch the vase life by a few additional days.

Close up of blush cosmosFor a small investment of time and garden space, you will be able to fill your house with these cheerful flowers all summer long.

I would love to hear your experience with this wonderful group of plants. Do you grow cosmos or plan to add them to your garden this coming season? If so, what are your favorite varieties?

 

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133 Comments

  1. Maaike on

    When are your Cosmos for sale?? Thank you!

    Reply
  2. Maci on

    I was wondering if you use preburned tarp to grow Cosmos? I couldn’t find anything stating that you did but I wanted to make sure. I live in Texas and I am going to try and sow directly into the ground. If you don’t use the tarp how far apart do I need to sprinkle seeds? Don’t want to overcrowd them (if that’s and issue) but while also choking out weeds. Thank you for your help! You’re an inspiration and I’m so excited to get my hands in the dirt this next season with all the knowledge I’ve learned from you.

    Reply
    • BriAnn, Team Floret on

      Yes, we plant cosmo seedlings into landscape fabric holes to help keep the weed pressure down. Happy planting!

    • BriAnn, Team Floret on

      They may just need more time, more sun, or you can give them some fertilizer higher in phosphorus to help with bud development.

  3. Jody on

    I purchased a pack of the Cupcake Cosmos, and I have to say- they are the prettiest, fluffiest and most luscious cosmos I have ever seen! The other gardeners adore them and they are the eyecatcher of the garden- especially in the evening sun.
    They are single and double blooms that start out whiteish in the morning and by afternoon have blushed on the surface with a magnificent light pink ( toward blue, not yellow). I will grow these every year! Tall plants with tons of blooms!

    Reply
  4. Maggie on

    Like Valentina below, I live in zone 7a. The seeds I purchased from you sprouted (every one of them!) and gave me a ton of foliage, but not many flowers. I love Cosmos, and would appreciate advice on how to encourage more blooms. Should I fertilize more or do they require certain nutrients in the soil that I may be lacking? In reference to another comment about your seeds, every single seed I’ve purchased from you has been amazing; I can’t say the same about other sources. I recommend your seeds to everyone I know.

    Reply
  5. Valentina Castano on

    Do you fertilize them after sprout? if yes how often with the compost tea??? thank you
    I planted I used your seeds & other seeds germinate very good all is great, I pinch them, at this time I found the flower not very strong.
    I am in zone 7a
    Thank you

    Reply
    • BriAnn, Team Floret on

      We do a compost tea root drench every few weeks throughout the growing season.

  6. Scarlet on

    Thank you for all the advice that didn’t work. This is not the first time I purchased seeds from you that are just absolutely no good. Out of a whole packet only one sprouted but didn’t survive after the dome was taken off. I now see why you dot sell often-you are a scam.

    Reply
  7. Ashneet on

    I am happy I came across your page. Planning to grow them soon.

    Reply
  8. Angela Ni on

    Is it too late to sow the seeds now? Or we still got time for them to grow. Zone 7

    Reply
  9. Kathryn Ward on

    Hello from New Zealand, I have grown cosmos before and they are an essential summer flower for me. I am very impressed with all of the different varieties that you have, they are truly beautiful. I have not seen so many different ones here in NZ. So pleased that I stumbled upon your site. Cheers Kathryn Ward.

    Reply
  10. Paige Hooper on

    This is my first year in Central Florida growing Cosmos. I am so excited and cannot wait to share them with friends.

    Reply
  11. Suzanne on

    I love these helpful resources. It would be great if you could offer each of them in a printable format (no photos necessarily, just the written information.) Perhaps a link at the end of the article. Even charge a fee if necessary due to the tremendous amount of work that goes into informing all of us (and Thank You for that!)

    Reply
  12. Dr. Sonya Pancucci on

    Throughout my childhood I remember cosmos in our flower beds and I hope to create something similar at my home.

    Reply
  13. Maggie Schwenk on

    I’ve bought all my Cosmos seeds from Floret and they are quickly moving up my list of favorites. I had Cosmos still in Ohio through November. My tallest one was well over 7 ft tall. They are so colorful and unique. Your resource blogs and books have helped me so much. Thank you!

    Reply
  14. Heather Bright on

    I grew cosmos for the first time last year. They did ok. I was desperate for some greens in early summer for my arrangements and was told you could use the foliage for flower arrangements. I was thrilled and cut a bunch for my farmers market bouquet. I was so disappointed when all of the foliage wilted at the market. That was a disappointing day. Is there a way to keep the foliage from wilting in the heat?

    Reply
  15. El on

    Brilliant, mine always go floppy and straggly!
    What is the best type of soil? Thanks!
    El

    Reply
  16. Flower lover on

    Most definitely; they love poor well drain soil

    Reply
  17. Caroline Viefers on

    How do you recommend to harvest Cosmos seeds? Can I cut the stem when the seeds are still green and let them dry indoors or do they have to stay on the plant to dry out?

    Reply
    • BriAnn Boots on

      It’s best to let them turn brown and dry on the stem before harvesting them.

  18. Stacey Murphy on

    Cosmos prefer unamended soil. Don’t fertilize.

    Reply
  19. Bieneke Loevendie on

    I planted most of the seedlings in rich soil. These seedlings became enormous high, green bushes -like a forest- with thick stems, but didn’t give any flowers. Can soil be too rich for cosmos (seedlings)?

    Reply
  20. Carmen Vair on

    The different Cosmos you are showing are beautiful……are you selling any seeds?

    Reply
    • BriAnn Boots on

      Yes, we’ll have some beautiful varieties available in our Shop November 1st, 2022!

  21. Juanita on

    Wondering if you ever fall sow the seeds as I know someone who had them come back year after year if let dry on stock and self?

    Reply
  22. Amy on

    I planted and pinched my Cosmos. They are starting to bloom but I am finding that at the base of the plant off shoots are trying to sprout but immediately turn brown. Not sure what is causing this nor what I should do. Any guidance would be appreciated. I have also been giving my plants a weekly feed.

    Reply
  23. Carissa on

    I cannot wait to try some of these varieties next year! My yard is part shade but getting sunnier as the summer approaches, so I tried some seedlings to test whether cosmos would thrive, and I’m so happy to say they are! A question: will seedlings spread, or do I have to buy and plant more to fill in? Thanks for the help!

    Reply
  24. Laura on

    Thank you for this post. I have just planted some young plants that are around 30cm high. I have pinched the top of the main shoot. As they grow side shoots should these be pinched from the centre too?
    Many thanks!

    Reply
    • BriAnn Boots on

      It’s not necessary to pinch the side shoots. As you harvest the blooms, they’ll continue to branch out from the cut point.

  25. L.T. on

    Thank you for sharing all the information regarding cosmos.

    My sister introduced me to cosmos and it didn’t take long before I developed a fondness for the flowers.

    I love your website. You share your knowledge as well as your passion for flowers. Your articles are always interesting and I look forward to reading them. Thank you.

    Reply
  26. Theresa S. on

    Should I make sure my cosmos get 1 inch of water a week? Or do cosmos prefer a drier environment than other flowers?

    Reply
    • BriAnn Boots on

      It can vary on your soil type and temperature outside, but if the top 2-3 inches of soil seems dry then it’s a good time to water them. Cosmos can tolerate a little more drought than other flowers. I hope this helps!

  27. Jo B. on

    Funny cosmo story. I was out of town and my husband, being kind and helpful, pulled weeds in one of our flower beds. When I returned home he very proudly walked me through his efforts, which included a peak into the yard waste container to show me the largest weed he had ever seen. He was surprised I had missed it as it was almost 3 feet tall. Yep, it was one of the cosmos I had planted. Fortunately I was able replant and it flourished and bloomed. We called the Resurrection Plant from then on and still laugh about 20 years later!

    Reply
  28. Usha Gupta on

    Thank you for the great information. I love Cosmos but didn’t know all these varieties.

    Reply
  29. Liz on

    Thanks for the tip!

    Reply
  30. Wi on

    Oh, yes, I would also love to know how to save cosmos seeds. Great post by the way!

    Reply
  31. GA on

    If your cosmos aren’t blooming, add phosphate. Is use Jobes Bone Meal. Makes ALL the difference!

    Reply
  32. Franziska on

    I always loved Cosmos, but I didn’t know that there are so many different colors available, in my garden I grew the simple rose ones and white one. I definitely try more different varieties.

    Reply
  33. Maggie on

    How do I save seed from cosmos?

    Reply
  34. Anissa on

    These are ALL gorgeous. I tried to grow a mix this year, but they turned out… meh. I put some in a pot probably planted too close together and they got plenty of light but they haven’t bloomed much. I’ve probably cut a small handful but that’s it. I have some I planted in partial shade too, they probably only got 4 hours of good sunlight and did NOT do well at all, so I know where I failed there. BUT there’s always next year and now I know better. I already have some Xanthos ready to go, so exciting. I may try them in my greenhouse instead of outside to see if I get better results. Now I just need some Apricot Lemonade and Daydream in my life! ;)

    Reply
  35. cristina on

    I definetly love Cosmos. I noticed that you don’t have the “Sulphureus” variety. It’s an exciting orange color, very brilliant. If you want I can ship it to you. If law doesn’t allow that to me, I can come personally!!! ;-))
    Cheers from Italy, Cristina.

    Reply
  36. Claire Koch on

    I grew cosmos four years ago. They were amazing. Each year since then they haven’t flowered😥
    I tried not feeding them?

    Reply
  37. Martha on

    Cosmos were doing great – about 8” tall – stems “cut” by something which does not eat the leaves – just leaves the stem on ground?

    Reply
  38. Pat on

    How do you after cutting cosmos make it last 7 day

    Reply
  39. Del on

    You can buy Cosmo seeds at Canadian Tire & Wal-mart.

    Reply
  40. Anna on

    Can I pinch my cosmos more than once? Or is it better to do it once, wait for blooms, and harvesting will cause more branching? Note: I just have mine scattered throughout my raised beds for cut flowers for myself & pollinators.

    Reply
  41. Debra Rosenberg on

    I find your updates, books and videos so helpful! You’ve changed the way I garden and made me a better gardener. Thank you from the bottom of my heart!

    Reply
  42. Emily on

    You mention staking, and then I see from one photo that you’ve used netting, which is better? I’m feeling like staking will be an overwhelming task with so many plants. If netting is preferable or at least acceptable, can you tell me the height at which you place it? I have my zinnias at 12″. Would cosmos be the same? Also, could corralling work or them? Thanks!!

    Reply
    • Team Floret on

      Yes, we do! We’ll have our seeds available in January.

  43. Johanna on

    This an encouraging and informative post about a flower I’ve been interested in trying. Your beautiful photos of a Cupcake Blush brought me in from Google. As a novice gardener, zinnias gave me much pleasure last season but with delayed gratification, as they didn’t bloom until the height of summer. After reading your tips and seeing these varieties, I’m prepared to dedicate much of my space to the beautiful Cosmo!

    Reply
  44. Pam on

    I received my cosmo seeds from Floret ant
    Planted them here in zone 6 about 3 weeks ago
    Inside my small greenhouse along with other seeds from Floret. The cosmo and the other variety of seeds popped up before any other seeds I had sown. Next year I’ll be sure to order much earlier so seeds are not sold out. I ordered what was available and I’m glad I did. I also received the cut flower book and Dahlia book which have been a great joy to read and thumb through. I’m so glad that I found Flora Farms.

    Reply
  45. Julia Evans on

    Cosmos was the very first seed that successfully grew! I’ve got the “bug” now and have hundreds of seedlings in my dining room. Actually threw out the dinking room furniture and the entire room is dedicated to seedlings.The potting bench is in the living room! All from one seed that made it planted directly in the garden. I’m planning on starting at least 100 cosmos today! It’s a little late but I was doing 4 milkweeds herbs etc. my led lights and warming mats are all ready! Love your article and I’m going to look for some variety’s you mentioned. Thank you for a feel good article!

    Reply
  46. Sue on

    If I lived near your farm I would work for free! You could pay me with bouquets of flowers

    Reply
  47. Donna on

    Hello:
    Thanks ever so much for your helpful information. I am planning on planting a cutting garden this year trying several new varieties and unsure of how many cosmos to plant. I would like to start the cosmos indoors to get a jump start on the season. I take bouquets of dahlias, gladiolus, delphiniums and sunflowers to church on Sunday and want to make bouquets from some of the earlier blooming flowers. To me flowers are meant to be shared.

    Reply
  48. Julia M Oliver on

    I love your passion, your generosity with sharing your knowledge of flowers and how they ‘work’. If I had another 25 years I would want to be working on your farm. Thank you for all you do and all you share.

    Reply
  49. Teresa Angotti on

    I’ve purchase my first cosmos seeds to star indoors regrettably yours were sold out due to just learning about Floret . Next year I’ll get a head start and purchase early! You make it all look like a dream !

    Reply
  50. Anne DeCraemer on

    Just wondering how you manage slugs? Do you need start to manage immediately when you plant seeds or seedlings and what products do you apply? I have tonnes of slugs and need to start taking them seriously as I would like my plants to make a full expression. Thanks!

    Reply
  51. Eva on

    Just discovered you guys. How inspiring! I am planning a cutting garden, purely for pleasure, and you have given me so many ideas.

    Reply
  52. cindy ingram on

    Should I direct sow in the fall for spring blooms? Zone 8b.

    Reply
  53. alison hall on

    These are the most amazing flowers and I am still in october having my cosmos buds come into bloom. I am not sure how to cut back for the winter so any help would be appreciated

    Reply
  54. Kathy on

    These are absolutely gorgeous!! How much sunlight do they need and how tall do they get.

    Reply
  55. andrea on

    I have had HUGE success with the “Cupcake” Cosmos varieties I received with my book for Mother’s Day. They have brought me and my Spokane neighbors a lot of joy :) I am curious, can the seeds be harvested and used for next years’ garden?
    Thanks so much!

    Reply
  56. Anjie on

    Hi I have been collecting the seed heads from a field of wild flowers that was planted on a council estate but I will be buying the yellow and apricot ones, I’ve never grown them before but look forward to doing so and increasing my colour palette

    Reply
  57. Rachel Churchill on

    I planted the Purity variety in the same space i did Zinnia’s and Sweet Peas. Zinnia’s and sweet peas are doing wonderfully but the cosmos are enormous almost treelike stalks yet no blooms. Any ideas on what i may have done wrong? Literally about 4 feet tall and not one bloom in sight. So sad:)

    Reply
  58. Ranelle King on

    Does anyone have any advice for cosmos that will not bloom? I have a bunch of plants growing beautifully from fresh Floret seeds but not one single bud has appeared. It’s mid-July in TX and I do not understand why all I have is foliage.

    Reply
  59. Theo Denoncour on

    I’m growing a dwarf cosmos this year in my vegetable garden. Should I still pinch it?

    Reply
  60. Lydia on

    I am DEFINITELY “Crazy for Cosmos”. My favorite varieties are Purity, Double Click, and Seashell. A couple quick tips are to pinch cosmos as soon as it reaches 6″ in height to get the best form and branching, to start early for the earliest blooms, and that you can bury their stems, like tomatoes, to give them a better rot system and give more stability. I hope someone finds this information helpful.

    Reply
  61. Jennifer on

    No, these are true annuals. I keep them blooming until Oct or Nov in my zone 9 garden by constantly cutting the flowers but eventually they give up and die back. For comparison I can get two or three years out of my petunias.

    Reply
  62. Lulu on

    Hi there, we have a small growing space, where we grow predominately annuals for selling as cut flowers. We have planted are first lot of cosmos. Once the sweet peas are over , I was thinking of preparing the bed for cosmos, will that be too late in the season though? I think our sweet peas have another two weeks to go. Thanks

    Reply
  63. Anh D on

    If planted in zone 9, could these become perennials?

    Reply
  64. CC on

    I grew cosmos for the first time last year and LOVED them! This year I am in a little different set-up and will not be able to start the plants inside. I will need to do a direct planting into the ground. These are for my personal yard, so there will be a few beds, but not outstanding amounts. I live in Utah and we have a lot of slugs, potato bugs, and grasshoppers. I am concerned about the sprouts getting eaten up before they can grow. Do you have any natural – diy suggestions on how to prevent insects from eating the sprouts? Thanks!

    Reply
  65. Irene on

    Hello Floret Team!
    I absolutely love cosmos and how airy and light they are. However, the few times I have tried to grow them I grow only beautiful green foliage! I have fertile soil as I have been amending with compost and mushroom manure through the years so I can grow roses and other fertile soil loving plants. I am assuming this must be the reason and I am wondering what you can suggest adding to my soil to grow cosmos flowers? Thanks very much and I love your website and I look forward to all the email posts.

    Reply
  66. Beth on

    How do you stake the cosmos?

    Reply
    • Angela, Team Floret on

      Hi Beth,

      We recommend using Hortonova netting to support them.

  67. Heather on

    Cosmos grow beautifully in full sun in large pots for the deck. I do it all the time. Such a lovely flower.

    Reply
  68. Deb Scott on

    My fondest memory of cosmos was combining them with my first plantings of new asparagus. As you know, you cannot cut asparagus for the first year or 2 to establish it’s bed before harvesting for a delicious meal. There is nothing more lovely than seeing a wonderful row of cosmos flowers and feathery fronds of asparagus greenery dancing in a summer breeze, giving hope you can be patient for a taste someday of the forbidden fruit, and pluck posies without guilt!

    Reply
  69. Gayle Doyle on

    I’m totally in love with all you do, you’re living a dream. I don’t know you personally but I am so proud of your amazing accomplishments.
    I purchased the book for myself and also my lovely daughter in law, Kate.
    Looking forward to seeing you on Magnolia channel in the fall.

    Admiring you, your husband, and staff ,your beautiful life.
    Fondly,
    Gayle Doyle, MI

    Reply
  70. Kristi Hein on

    Cosmos did just fine for me in a big pot last summer. I sowed Sensation Mix 4/15, and 23 of 24 cells had sprouted by 4/21. Notes: I planted five potted-up starts in a big pot 6/24. Also planted out in the community garden. In our unfenced garden we have lots of deer, and they never touched the cosmos. They bloomed gloriously through the summer. I’ll be growing Rubenza and Apricot Lemonade this year.

    Reply
  71. Jane on

    How much sunlight do cosmos need? There is an area of our backyard that doesn’t get much sunlight and looking for a pretty but simple flower to plant there! :)

    Reply
    • Angela, Team Floret on

      Hi Jane,
      They need at least 6-8 hours of direct sunlight to flower properly. Hope this helps!

  72. Emily on

    Hi! Any thoughts on growing cosmo seeds in a large flower pot or container? Would love to have these on our deck!

    Reply
  73. Lee Ann Marienthal on

    I’ve just sown my first seedlings in southern California. Looking forward to watching them grow. I think I’ll have an abundant amount of time to do so. ;-)

    Reply
  74. Lisa Miner on

    I grew Cosmos for the first time last year and was amazed at how vigorous and tall the plants grew. (Here we are about a zone 5) I had blooms to pick all season! Will definitely grow more this year. I bought a pack of your Apricot Lemonade to try and can’t wait for the snow to be gone. Here in the North Okanagan region of BC, would you believe we still have 2 feet of snow covering our yard? Crazy. In town, the tulips are coming up. I’m patiently waiting but keeping busy planting seeds. Thank you so much for all your knowledge, hard work and sharing! I love your books and blogs and am so excited to try your seeds this year!

    Reply
  75. Marilee on

    I have only tried growing cosmos in
    Containers however, after reading this
    Artical I am inspired to give them a
    Try in my above ground garden.
    Thanks for the inspiration!
    Best Wishes!

    Reply
  76. Kristin Teske on

    Sophia, for that same color combination and feel, you could sow some of their scabiosa seeds. Floret is selling a maroon red that grew beautifully in my yard last year.

    Reply
  77. Lea on

    Please advise the specific growing conditions you suggest for Cosmos, eg, how much sun do they require, what type of soil, etc.

    Reply
  78. Ann Keppler on

    I plan to start growing cosmos this summer
    How much space will I need.

    Reply
  79. Irene on

    I have grown cosmos in the past and I noticed that the greenery of the plant grew large and bushy but there were hardly any flowers. Is this because the soil was too rich or moist? I hesitate to grow them again even though I love them because most of my garden has good quality and moist soil. thanks.

    Reply
  80. Sophia on

    Have you ever thought of carrying chocolate cosmos? I saw them in multiple places last year, especially stunning with deep orange dahlias, and have been thinking of trying them this year.

    Reply
  81. E Sloan on

    Can you post pics of individual stems harvested as cut flowers? I have been cutting most of the side shoots off, when giving to the florist as cut flower. Should I be leaving them on? Do you treat your Cosmos after harvest? If so, how? Thank you. After a few weeks of harvesting, my flower stems are getting shorter-12″ or less, or having a huge curve or bend from where the previous flowers were cut from. Is this normal? Is there something I should or should not be doing? Thanks in advance.

    Reply
  82. Kate on

    I harvested my own cosmo seeds from my community garden last year. They were purple, pink and white. I have about 8 cosmo plants this summer, they are all doing so great and health and beautiful. The only thing is, they are all ORANGE! Why is that? I went through all my pictures of last year and there weren’t any orange cosmos.

    Reply
  83. Victoria Leitch on

    Hi , do you plant cosmos into your weed mat fabric?? Thanks Victoria

    Reply
  84. Shelly on

    Thank you so much for all your information on growing cut flowers. I am just starting my business this year after 5 years of contemplating about it. Growing season here in NY is short; and you really have to be careful about frost. We just had our last frost, I hope, this week. Thank god I had hoops so that I could protect what I had planted. I feel like I am so behind; but I am glad I didn’t plant most of my garden yet. Very cold and wet spring here. I know now to not jump the gun early. Will have everything planted this week. As far as Cosmos do you mulch? Also do you use netting like you do for zinnias and snapdragons or stake individually or glow closer together to support them? Oh when harvesting what temperature water should be used in buckets? Do they need to be stored in cooler or not? Again thanks sooo much for sharing with us.

    Reply
  85. Lynda Eustace on

    I would love to hear Floret’s take on the question of fertility! Do cosmos benefit from fertile soil or do they prefer ‘average’ to ‘sandy’?

    Reply
    • Team Floret on

      Hi Lynda,
      We grow our cosmos in fertile soil, which is naturally a touch sandy because of our location. Here’s how we generally prep our beds: https://www.floretflowers.com/soil-preparation/
      For us, the fertile soil has really helped our plants thrive! It also helps with insect and disease pressure.

  86. hMh on

    I live in very cold zone 4a-b w a short growing season and last frost at end of May…wanted to share w cold climate growers (Ontario) that starting cosmos inside is a waste of time and space! I grow every year in poor Sandy soil -which they seem to do best in (compost made them too tall and leggy for me) and let half my bushes self seed in place and freeze over winter … and those seeds start sprouting on their own and are stronger and do better by the end of May than all the work of starting them inside !… i then toss down a bunch of seed collected from the previous summer when I start to see sprouts -very close together, no longer spacing them in rows, as I find the branching of ea. Stem helps to hold them upright and they intertwine into one massive 10′ long (by about a yard wide) hedge…
    I don’t find it difficult to get at them for cutting flowers because it’s a very narrow row but this year I am also going to try some new varieties and expand it to double width. I don’t usually start to get flowers until August but they flower continually up until the first frost around Halloween and some years are still going into Nov.!
    It’s great to see end of summer and early fall when so many other flowers are on their way out…I love how heatwave hardy cosmos are and how well they do if I can’t get to watering in the dry years. Some years i’ve only watered once or twice the whole season and they’re so low maintenance, they have managed to put out an abundance of blooms on rain alone ! They love being in just sand but I do mulch heavily every time I cut the lawn with grass clippings since Sand doesn’t hold the water very well, and all they need is a good drink once a week.
    Thank you for bringing us beautiful new varieties and colours Floret!! if I was lucky enough to have a full sun part of my property I would have a field of cosmos ! They are so lovely the way they move in the breeze and look delicate but are such a hearty low maintenance plant. They definitely don’t last long in the vase and I would love to know what kind of flower food you recommend ? and thank you for the tip on cutting before pollination …cheers!

    Reply
  87. Tamara M on

    Your pictures get me in trouble every single time! Last year was my first year to seriously grow cosmos. I had planted them previously, but with little luck. They are beautiful blossoms and I love the airy blooms and foliage. This year, I’m playing with Double Click Mix, Purity, and Seashells – all from your store. Love your idea to succession plant. I’ll start about 1/2 my seeds inside and plant out in early May and will plant my seeds outside at the same time. Thank you for what you do. You are inspiration and courage sandwiched between beautiful photos. I can’t wait for the snow to leave! Your post feels like spring!

    Reply
  88. Janet L Kuenzi on

    A European seed company lists cosmos and strawflower as hardy annuals which was such a revelation for me.
    They are always listed as HHA in seed catalogs. Didn’t grow cosmos this last season, but I did attempt to grow strawflowers and they withstood considerable frost and survived to about 29.
    I live in the Atlanta area and neither of those ever does well for me. Because of the high summer heat and humidity here, hardy annuals bloom April and May and raggedly into June and then they literally die or just look awful and one feels compelled to pull them out.
    I received a bonus pkt of Cosmos with my bulb order and will likely try one more time. I have often read that cosmos prefer rather poor soil so I followed that advice. I will give them better soil this year and may have different results.

    Reply
  89. Laura on

    Thank you for the Cosmos inspiration! I’m looking forward to trying several of these this summer.

    Reply
  90. Jody on

    Can I add Cosmos to my peony bed? It’s the only place I get enough sun. Will they impact my peonies foliage? Peonies are such a short season it would be nice for the bed to do double duty.
    Thanks!

    Reply
  91. Robin on

    I have rabbits visit my yard often. How do I protect cosmos from them?

    Reply
  92. Patti on

    Last year I ordered several varieties of Cosmos from Floret, and Erin’s absolutely right, they are truly the workhorses of a cutting garden! I had bouquets all summer for myself, neighbors, family & friends. Sooooo simple….I bought a small heat mat and seeded them indoors and within 3-5 days, had plants! After growing them up a little they got planted outdoors, I pinched them back a little later, and they were on their way. Deer leave them alone, too. Nothing not to like about Cosmos, give them a go!!

    Reply
  93. Laura on

    Very helpful post, thank you! Sometimes I find it difficult to tell the difference between several similar-looking varieties, so I especially like your descriptions here.

    Some other varieties I like are ‘Bright Lights’ and ‘Candy Stripe’. I’d love to try ‘Psyche White’, ‘Velouette’, and ‘Apricot Lemonade’, but I had to hold myself back from getting those this year because I am moving and trying to limit what I’m starting from seed inside… sad but next year will be more exciting!

    Reply
  94. barbara on

    I grew your butterfly snapdrangons last summer…..beautiful…..so far they are wintering over…. my question is should I pull last years plants and start new seedlings or will last years plants perform as well or better than new starts….thank you

    Reply
  95. Susan on

    Cosmos are supposed to be among the easiest flowers to grow, but I’ve had little luck with them. They always start out fine, but soon the leaves start browning from the bottom up. I live in Atlanta where summers are hot and humid. I’ve tried in a couple of different spots, but the same thing always happens. I’m contemplating waiting until midsummer to plant some – I’ve read they like late summer/early fall conditions.

    Reply
  96. Sford on

    Gloria. Yes you can plant them in pots. I do and put the pots outside my back door. Just remember to keep them well watered and feed them once a week or so

    Reply
  97. Nancy Ashland on

    Can Cosmos be planted I the Phoenix, AZ area soon in order to enjoy them before the heat of summer?

    Reply
  98. Cara on

    Are there specific stakes you recommend? Thank you!!!

    Reply
  99. Sarah jo on

    For everyone who didn’t get flowers until august, cosmos are a bit daylength sensitive. If they’re established before day length reaches 14 hrs, you’re fine. If not, they won’t really flower until daylength gets back down to 14. This is important for those of us waaay south who have longer daylengths arriving much sooner in the season :) start seeds indoors 4 weeks before last frost, transplant and you should be fine.

    Reply
  100. Erin on

    I’m in Australia where it’s mid-summer – if I was to sow the seeds now, would they still grow and flower before autumn (fall)?
    Thanks

    Reply
  101. Nitasha on

    Hi I would love tips on where to cut them for long stems in a vase – this sounds so obvious, but are they still ‘cut and come again’ like you and Sarah Raven describe even if you’re cutting long, branched stems with multiple blooms? Thank you!

    Reply
  102. Diana on

    I grew cosmos from seed last year and they didn’t flower until August. Then they bloomed until frost in November! I didn’t pinch them back, but I will try that this year sand at if they get bushier.
    They l the only thing you mention that I didn’t thing would be necessary for cosmos is staking. How seriously will your varieties need staking? Can I get away workout?

    Reply
  103. Shelley sturdy on

    I love grow cosmos, such great floweres. I have had some success from harvesting my own seeds, but this year I cant wait to sow your lovely seashell mix :))

    Reply
  104. Rachelle on

    Thanks so much for the info! I just received some cosmos seeds yesterday and I’m excited to see them blooming later this summer. Being new to flower farming game I’ll take all the info I can get so keep it coming!!!!

    Reply
  105. Kristine Daniels on

    I grew snow puff last year and it was awesome. It was my first time growing cosmos. They were 5 feet tall and tons of beautiful blooms. I’m growing them again this year with the addition of the double click bi-colour rose. I will also try succession planting them. Last year I planted them as a second crop behind a crop of stock. They bloomed till frost but the best blooms for cutting were earlier on.

    Reply
  106. Adrienn Magyar on

    Thank you for this an all past and future articles! :)
    Im just sad, that in my country (Hungary) there is no big seed company or farm who is selling these varieties.

    Reply
    • Team Floret on

      Hi Adrienn–
      Have you checked Sarah Raven? I believe she ships throughout the EU. We also can ship seeds to almost all European Union countries. Hopefully you can snag some seeds for your garden this year!

  107. Mercedes Ivener (Honeysuckle Hollow Florist) on

    Cosmos are my very favorite cut flower because they always produce so many blooms with very little work, plus I love their long, airy, dance-like demeanor in a vase. In the language of flowers, they stand for ‘joy in love and life’ which makes me love be them even more . I grew your rubenza last year and loved it for my event flowers but my very favorite are the white varieties. Someday I think I would simply grow a meadow of white and full my home with them . I did not order my seeds from you early enough to buy the cupcake variety but will hope you get some more in so I can try those. They look marvelous. Thank you for all your research and discovery of unique flower varieties. Keep up all the good work. I love following all of your endeavors and fondly remember back to that magical workshop with you years back.

    Reply
  108. Gloria Nikkel on

    Is it okay to grow Cosmos is a large wooden barrel? That’s really all I have to grow my flowers in. Any tips for growing my flowers in barrels?! I have double click and intend to buy some cupcake blush when they come available!

    Reply
  109. Joy on

    I don’t have a particular green thumb or fingers for that matter, BUT I’m stepping out of my comfort zone and trying these pretty babies this year. Excited to see the outcome! I will post a picture to share the “joy” if I can!

    Reply
  110. Miranda on

    Hi, I would love it if you could do a series of photos showing the pinching techniques on a time lapse because last year I planted cosmos and attempted to pinch them out but they ended up extremely tall (1.5m) and not very bushy compared to a shop bought one which was much lower 0.75m and a real bush. I had loads of blooms nevertheless but I’d like them to be less leggy. Many thanks, Miranda

    Reply
  111. Stefanie on

    I grew cupcake last year. They grew realy big but didn’t flower before august. I suppose there was to much nutrient in the soil. This year I will give IT another try.

    Reply
  112. Christine on

    I have yet to grow cosmos from seed but this is the year! Thank you for the inspiration and the information!

    Reply
  113. Christen Phillips on

    I have a crazy Cosmo question! I’m super new to gardening (because up until now I’ve always lived on the second floor of an apartment building) but I’m obsessed with the idea of turning my yard garden into a beautiful self seeding wildflower field. It’s a little tricky finding the right mix for our Southern California zone but I’m working on it. Cosmos are great and such terrific self seeders, but I have the weirdest results when they grow up. I get either one of two versions, tiny skinny little cosmos that give me one or two flowers and then dry up… or on the opposite side of the house I get literal TREES. I pinch off the leaves to get more blooms and they grow to over five feet and up, the stems at the base are easily 1/2 inch in diameter, and sometimes they grow so heavy they tip over. I get a lot of blooms on these! But… they are kind of freakish.

    Any insights?? I’m sure this has something to do with the soil/water/light. How big are Cosmo’s supposed to grow?

    Reply
    • Team Floret on

      Hi Christen,

      If you aren’t doing it already, I’d definitely pinch them. Here’s how it’s done: When plants are young, between 8 to 12 inches tall, take sharp pruners and snip the top 3 to 4 inches off of the plant, just above a set of leaves. This signals the plant to send up multiple stems from below where the cut was made, resulting in more abundant flower production as well as longer stem length.

      Also, are you staking them? This will help them not fall over. Between pinching and staking, you should have gorgeous plants this year!

  114. Shannon on

    I started some a few years ago because I remembered how much my Mum loved them. They’ve kept reseeding themselves in the garden and I just love how tall they get and the beautiful feathery foliage. This year I will be starting some of the double click mix to include in market bouquets as I no longer want to strip my household beds of their beauty to keep up with demand. I used to bring flowers to decorate my booth. Now I sell them alongside my veggies and homemade jams, jellies and pickles.

    Reply
  115. Shelly on

    Last year was my first time growing cosmos (I grew Cupcake Blush) and the plants were SO HUGE I called them flower bushes ? lol! The butterflies and bees loved them!

    Can’t wait to grow more this year – I’m adding Double Click mix and Rubenza to the garden this year!

    Thank you for all your recent blog posts and sharing your knowledge with the world! There’s so much good info here!

    Reply
  116. Angie on

    I love cosmos ! I’ve grown seashell in the past-so pretty & so easy. I’ve been quite taken with chocolate cosmos the last few seasons -had a hard time finding them -but I got lucky that an local greenhouse had seedlings last year -they were lovely but I had trouble with them falling over -I had.to put in some support-i think they may not have been getting enough sun -I will try a different location this year I’ve ordered Rosetta & Xsenia from you-they are so beautiful & looking forward to seeing if I can achieve something close to your gorgeous results . Thanks so much for sharing your experiences, your advice & your passion for flowers.

    Reply

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