Bradley McCarson, South Carolina

Basal rot treatment

January 4, 2020

Categories: Basal Rot, Bulb Information, Diseases and Pests, Fungus, Growing Daffodils, Hybridizing, Planting, Pots, Science, Soil, Weather and Temperature

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A few prized tetraploid tazettas became infected with basal rot. I invented a treatment that successfully cured them. I am not scientist but a gardener and breeder of Narcissus who likes to try new things and experiment.


In the spring the bulb’s basal plates were infected with a pink fungus due to heavy rainfall and lack of drainage. I decided to scrape away all of the rotten and infected flesh with a blade and then I soaked the bulbs in a 3% medical grade hydrogen peroxide solution for 48 hours. I then let the bulbs dry out indoors with ample air circulation until autumn. They were then planted in a fresh soil mixture mostly comprised of pine bark fines and sharp sand. By December all of the treated bulbs emerged healthy with strong roots and a recovered basal plate and appear to have been cured of the basal rot.


The bulbs did not flower this season but if they continue to recover I expect blooms next season.


Has anyone had success with treatment of basal rot in Narcissus?

4 responses to “Basal rot treatment”

  1. Bradley McCarson, South Carolina Bradley McCarson, South Carolina says:

  2. Ross Hornsby, Alabama Ross Hornsby, Alabama says:

    Looks successful to me. Did the basal plates recover over the summer while in dry storage?

    I’ve heard about the use of hydrogen peroxide by orchid growers, and I’ve used it myself to soak terra cotta pots between repottings (they fizzed a lot). I never thought to use it on the bulbs themselves. My main strategy is prevention of rot, but I learned the hard way last summer that some kinds of daffodils don’t like to be stored dry over summer. The tazettas and jonquillas were fine but I lost some trumpets, poetazes, and small and large cup cultivars. It seems like for them I’ve had the best success keeping them potted but leaving them inside in the cool  over summer without watering them. I wonder if a weak hydrogen peroxide drench could be applied at their last watering before summer.

  3. Ian Tyler, England Ian Tyler says:

    On reading the given description for Base Rot it is not what I would
    expect, for me it a total mass of black brown rotting bulb with a unique
    pungent smell.
    I realise there could be climate differences but even so pink mold that can
    be wiped/scraped off, sound like some form of fungus but not basal rot.
    This would be the reason for the bulb surviving the treatment.

  4. Bradley McCarson, South Carolina Bradley McCarson, South Carolina says:

    The bulb basal rot extended well into the basal plate and caused death of the tissue. The cause is Fusarium oxysporum f.sp. narcissi. It is a fungus that invades healthy tissues. The bulbs did heal over the summer under dry storage and continued to recover during growth. Some bulbs were severely infected and I cut all of the dead tissue away but leaving as much basal plate and healthy tissue as possible. I was surprised to see the worst ones recover when almost all of the basal plate had been removed.