Shop Products
Houzz Logo Print
sonority

Avoiding leaf burn when using Neem Oil?

sonority
12 years ago

I sprayed my violets with Neem Oil last evening; I'm trying to keep down an infection of powdery mildew and thrips.

This morning they have blackened burned edges; not so bad that it will kill the plants, but enough to make them unattractive, esp. if I need to repeat the spraying.

I used a premixed Neem Spray (packaged as Garden Safes Fungicide 3), as no where local had the concentrate. I kept the lights off afterwards and I blotted up any excess that pooled on the leaves.

I still got burned edges on the plants I sprayed.

Is there a way to avoid this? Is the prepackaged spray simply too strong for them? It is a 0.9% solution.

Unless my math is incorrect (which is possible I have a wicked sinus cold right now), 1 TBL of Neem per Gallon, which is what I've seen recommended for violets is about a 0.4% solution. It's a little higher in the premixed spray, but not overwhelmingly so.

Thanks.

Comments (5)

  • thominindy
    12 years ago

    Hi Sonority.

    Since no one else is jummping in i will give my experience. I use neem oil but not regularly. I always put my plants on an old shower curtain and spray them down thoughouly. I use this opportunity to clean my shelves. What I use is called 100% neem oil and I use it stronger than what is called for.

    I treat them afterwards like you do , sponge the centers off with paper toweling and keep them out of the light until the next day.

    Anyway my plants seem to love the Neem, they look so vibrant and healthy afterwards. I really don't think the neem I have been using would cause the problems you are describing.

    I always take the excess and spay all of my plants inside and out. They love it.

    Thom in Indy

  • sonority
    Original Author
    12 years ago

    Thanks for the response. The only thing I can think is that maybe there is something not listed on the label in the premixed spray. I'll have to order the 100% concentrate.

    Here is a link that might be useful: {{gwi:366806}}

  • lathyrus_odoratus
    12 years ago

    Sonority,

    I only use the concentrated oil, also. If I understand it correctly, not all Neem is processed the same, nor does it contain the same active ingredients. Cold processed - such as Dyna Grow's version - is considered the best as it contains azadirachtin - which they think is one of the more important components of Neem.

    I accidentally bought the Green Light version before I learned about this. Then I bought the Dyna Grow. Because I didn't want to waste the Green Light version, though, I decided to mix them together. I use 1/2 t per 12 ounces of water (quarter t each). I spray once a week, at night, after the lights are off. I put them back on the shelves without wiping up anything.

    I've not every had anything burn or be harmed. On another forum, just last week, we were talking about this. Some people have had the damage you've had, others have damage only to blooms, but not leaves. Then, others like me have had no damage at all.

  • sonority
    Original Author
    12 years ago

    Thanks for the post, Sweet Pea.

    I purchased the Dynagro version after my initial post, but have not used it yet. The other garden safe one, I've been using on my roses and peonies outside to keep the powdery mildew devil back.

    Hopefully it was just something in the Garden Safe version, an additive perhaps, that was causing the damage. I guess I'll know soon enough. :)

  • Bonnie Drews
    3 years ago

    I have found neem oil is well tolerated on some plants, but damaging to others. Neem oil appears to work well on the broad tougher leaf plants. On the other hand, it burns my ferns and shrimp vines. It should be noted that shrimp vines do not like any foliar spray, even 💦 water. I use a cold pressed variety of neem oil that I must place in the microwave to transform the oil to a liquid state. I heat my water until it simmers. I then take the neem oil and heated water and place it in the blender at the highest possible speed. This will give you properly emulsified neem oil. I believe proper emulsification is critical to obtain an even application of the neem oil solution. If you are unwilling to take these steps, it is better to use the pre-emulsified mixture.


    if you are fighting fungus gnat, I

    prefer mosquito bits. However, if you are dealing with a whitefly infestation, mosquito bits will do nothing. In my view neem oil takes a while to work and is not tolerated well by all plants. I try to use it as a systemic poison, but this method takes time. For the broad leaf plants, I prefer to use a dormant oil as a wipe. Unfortunately, it has been my experience that no one thing is a solution for all manner of pest control. Some people swear by cinnamon. Some people swear by diatomaceous earth. And then there are others who prefer insecticidal soaps. Dormant oil has its fans, but like neem oil, can damage foliage. Whatever you do invest in some sticky traps. They are non-toxic and yummy tasting to your pest(s). They are attracted to the yellow color. I wouldn’t be without them since you may think an infestation is gone, but after a few days you will see if you’ve cured the problem. You will also be able to correctly identify your pests. After you’ve identified your pest call the best grower/greenhouse in town to determine their specie recommendation for the treatment of African violets. You may want to glean more than one opinion. I’d suggest your state’s extension agent, but there expertise is more towards commercial growers than indoor hobbyists such as myself.

Sponsored
Through The Garden, Inc.
Average rating: 5 out of 5 stars21 Reviews
#1 Landscape Design Build Firm Serving Virginia/Maryland & DC Area