Coral-Vinca
Vibrant blooms, Annual Vinca

Vibrant blooms, Annual Vinca (Catharanthus roseus)

One of my favorite summer annuals is vinca.

Vibrant blooms

Stop by any nursery this time of year, and you will find flats full of their vibrant blooms, and there are many different colors available.

Vibrant blooms

From purples and pinks to bright reds.

Vibrant blooms

Vinca works excellent in containers or when planted in the ground.  They prefer well-drained soil in a warm, sunny area.

This warm-season annual enjoys regular watering and does best with some fertilizer, but don’t overdo it.  I usually apply a slow-release fertilizer when planting and follow up with monthly applications of a liquid fertilizer such as Miracle-Gro.  If you want to go organic, then you can just use a mixture of good potting soil mixed with compost.  

Vibrant blooms

Now some of you may have had the experience of growing beautiful vinca one year and the next year; you have a terrible time with them. Shortly after planting you notice your vinca beginning to wilt, and no amount of water seems to help.

Vibrant blooms

Has this happened to you? Extra water will not help because the vinca is suffering from a case of ‘Vinca Wilt’.  This is not the scientific term, but for those of you who like long scientific names, your vinca is likely the victim of a Phytophthora fungus, which affects the roots, preventing them from absorbing water – hence the dried out look of the vinca.  

This fungus lives in the soil and infects the roots, causing them to rot. It loves moist conditions, and so more water hastens the demise of vinca.  

So, what can you do? The fungal spores can last for months or even years in the soil. You can usually rely on one good year of vinca growth, but then the spores start to multiply, and by the next year, they begin to affect your new plants.

Vibrant blooms

I recommend using vinca for one year and then use something different the next three years. Of course, you can remove all the soil from your containers and sterilize the inside with a bleach water mixture and then add new soil, which can work for a few containers at home, but it is not cost-effective in a larger setting.  For me, it is not worth it either, because there are so many other beautiful summer annuals that you can use. 

I hope this solves any mystery surrounding vinca.  They are beautiful and well worth growing – for a year at least.

Noelle Johnson, aka, 'AZ Plant Lady' is a author, horticulturist, and landscape consultant who helps people learn how to create, grow, and maintain beautiful desert gardens that thrive in a hot, dry climate. She does this through her consulting services, her online class Desert Gardening 101, and her monthly membership club, Through the Garden Gate. As she likes to tell desert-dwellers, "Gardening in the desert isn't hard, but it is different."
19 replies
  1. Rosie@leavesnbloom
    Rosie@leavesnbloom says:

    We rarely are offered vinca for sale as an annual but it looks lovely in all those different colours. I never realised that the annual form had problems like this. I always thought that that fungus would only thrive in wet soils rather than in a dry desert one.

    Have a lovely Mother's Day weekend Noelle.

  2. Jim Groble
    Jim Groble says:

    Looking at the pics makes me want to run out and get some annuals. But we're still 3 weeks away from annual planting. it's 40 and raining. Great pics. jim

  3. Deborah
    Deborah says:

    I love vincas. They do so well in our heat and humidity. I think farther south in Florida they are perennials

    Enjoy the farm and Mother's Day!

  4. Curbstone Valley Farm
    Curbstone Valley Farm says:

    I love the look of impatiens, and when I moved to a warmer area I enjoyed using the annual vinca as a substitute, as it was similar in stature and available colors, but more sun tolerant. I must say though, I've never heard of vinca wilt, so that's interesting. Thanks for providing advice on how to manage it.

  5. Ami
    Ami says:

    I love vinca, and actually lots of vincas self seeded themselves in my garden, so I got a lot more free plants this year. About the vinca wilt you mentioned, I am not sure if I experienced some with my plant. Some of them just grow like a weed in the summer, and some of them just suddenly wilted and got the yellow leaves and nothing seems can save it. But I am satisfied with those that survived since they quickly grow to a bigger plant with lots of flowers last many months in florida.

  6. Annelie
    Annelie says:

    Ooooh and aaaaah!
    I want some of that brilliant red one to mix with the white one that has a red center.
    Have….. to…. have… it… now…..

    Annelie

  7. NellJean
    NellJean says:

    I call them Madagascar periwinkles. The purples are my fave, followed by the palest pink and the white. They freely reseed here. I think after they reseed a number of years, the fungus resistant survive and persist.

    When I read your post, I rushed outside and sure enough, they're coming up!

  8. Autumn Belle
    Autumn Belle says:

    I love to grow vincas too as I have a multiple of colours to choose from. They make the garden more colourful. Yours are lovely and thanks for the advice which I find very useful. Have an enjoyable visit to the farm and Happy Mother's Day!

  9. ShadowySteeds
    ShadowySteeds says:

    Apologies for posting this to your page, but my Outlook won't let me e-mail from a web page… something wrong with the configuration… What the heck is with the Chinese looking comments on the web sites?? I finally had to set mine on moderation so I can delete them! I noticed some other blogs had these as well. Thought one of you (well KNEW basically) would be more informed than I am and wanted to inquire. Don't these people have anything better to do??

  10. noel
    noel says:

    aloha noelle,

    happy mothers day to you, i loved your vinca post, can you believe they grow wild here…i did a mothers day tribue on my sari sari blog

    best,

    noel

  11. Brad
    Brad says:

    I wonder if you could just plant the vinca in different areas every year or if the fungus spreads out a ways from the original planting. Of course if you only plant it every fourth year, it will continue to be a special treat.

  12. Kathleen
    Kathleen says:

    I only grow vinca in purple ~ it's a perennial variety tho. Are these what northerners know as impatiens?? That's what they remind me of too.
    Hope you had a Happy Mother's Day too Noelle!

  13. pamsenglishgarden
    pamsenglishgarden says:

    Noelle, Very vivacious those vincas! Impatiens do better in my NE garden, though. Please keep the advice coming … I am storing all this useful info for when my son and his family move to Phoenix in August. Pam

  14. camissonia
    camissonia says:

    Thanks for the post, Noelle, as it brought back fond memories of the fuschia-pink and also white-flowered vincas we had growing in profusion in my childhood home in Taiwan. I think the subtropical climate there suited them and they often persisted as perennials rather than annuals.

  15. Pam
    Pam says:

    I take it but that thet mean flowers that grow in China they look like flowers that come from China. I don’t think it means anything about the Chinese. Is that what you mean? You sound offended. I don’t know any flowers that come from China but with those mountains I’m sure there must be some really beautiful flowers. Now you have me curious I’ll have to go look at China and see what kind of flowers they grow.

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