Shop Products
Houzz Logo Print
sakmeht

rust on nep

sakmeht
16 years ago

Just found some rust on my ventricosa and picked up some neem oil. Just wondering if I should dilute it? And how much? Also, should I spray everything in my terrarium or just take out the nep and hope it doesn't spread? I've got 3 gesneriads, 2 orchids, a pothos, a zebra prayer plant, a sun spot bulb, and a n. maxima in there as well... Looks like neem is pretty safe for most all plants. What do you think?

Comments (7)

  • ilbasso_74
    16 years ago
    last modified: 9 years ago

    I've not used it, but I seem to recall hearing that it can be nasty stuff straight up. I'm trying to find that source right now.

    I have Safer brand fungicide that seems to work. I believe that sulfur based is what you want.

    AHA! Here we go. I don't know if this'll help, but it is from the Sarracenia Northwest "Ask The Growers" blog:

    QUESTION:
    I just reviewed your blog regarding the use of Neem oil to control fungus and pests with carnivorous plants, and I noticed that you warn against using any preparations containing soap. In our local garden stores, Neem oil sprays are available for purchase for about $10 a quart (contents: 0.1% Neem oil). For $6 I ordered a can of the pure stuff (100% Neem) online that is enough to produce approximately 1000 gallons! If preparing your own solution, it is recommended to use distilled water and an excipient to dissolve the oil in the water, otherwise it clumps up. This is usually done with soap, however, as you've stated, this is contraindicated for carnivorous plants. Do you have any experience with any safe excipients, which will dissolve and disperse the oil in the water, but not harm the plants?

    ANSWER:
    I've never done this myself. The reason is that I haven't had the need to mix up that kind of quantity of pesticide in the nursery.

    I know that surfactant products are out there for use on horticultural products. The are often referred to as spreaders or stickers. They usually contain some kind of detergent. You could do a web search for these products.

    The reason we advise against insecticidal soaps is that most of the commercial varieties contain potassium salts of fatty acids. They contain quantities strong enough to cause bugs problems. If used continually, they deposit potassium in the soil. Not a problem for your rose bush, but deadly to a Venus flytrap. Many other horticulture products contain small amounts of surfactants, but not enough to be a problem for carnivorous plants.

    Personally I would be very leery of working with 100% Neem oil. First, 100% Neem oil can be toxic if accidentally ingested. A low concentration of 0.1% is considered safe for the average gardener to work with, but 100% is not. You must be extremely careful on using the pure stuff. The odor can also be extremely noxious, so work in a well ventilated area.

    Think of it like vinegar. Vinegar is commercially available as a food additive in concentrations of 5%. You will never find 100% vinegar (acetic acid) on the grocery shelf because it can be quite dangerous to work with. The fumes alone can definitely knock you out.

    The second issue is that commercially prepared Neem, even though proportionally expensive, have already worked out the chemistry and phytotoxicity issues. Getting a safe concentration of 0.1% is difficult, and you'll need to be extremely precise with your calculations and measurements. It will be very easy to double the concentration to 0.2%. How this concentration affects carnivorous plants is unknown. If you experiment with it, you must be willing to sacrifice a few plants until you can determine the phytotoxicity of your mix.

    We definitely have a couple of horror stories here in the nursery of getting too "gung ho!" with a new product just to kill everything we sprayed it on.

    In short, $10 for a quart of Neem oil is not a lot of money. You actually save money in time and needing to purchase expensive equipment required to work with the pure stuff. It's also not necessary or recommended to use Neem oil on a constant or regular basis.

    If at all, we spray our plants with Neem perhaps 3 times a year at the very most. Even then, we use it only if we deem it absolutely necessary to control a fungal or pest outbreak. At the most, we may go through a gallon of Neem per year. Given that your collection of plants is probably a small fraction of what we have here at the nursery, a single quart may last you for a couple of years.

  • sakmeht
    Original Author
    16 years ago
    last modified: 9 years ago

    Wow, thanks for the info! The stuff I have looks as though it's definitely diluted... 0.9% neem and 99.1% other... guess I was just wondering if I need to dilute it even further... but I think I'll go ahead and just test of a bit of leaf and see what happens...... if I don't get good results, maybe I'll pick up that Safer brand Sarracenia nw uses.

    I think maybe I'll just spray the plants I suspect might be infected and leave the rest alone... and see what happens! Thanks for the info.

  • sakmeht
    Original Author
    16 years ago
    last modified: 9 years ago

    So I also received a reply to my question from the house plants forum and a person there told me that the rust that I see attacking my nep is specific to that species and wouldn't attack my other plants... does this sound right? Just want a second opinion! If I don't have to spray everything I'd be SO happy! :)

  • petiolaris
    16 years ago
    last modified: 9 years ago

    Do you have a picture of the rust. I've never seen it on my Neps and was wondering if maybe I have and just hadn't recognized it.

  • sakmeht
    Original Author
    16 years ago
    last modified: 9 years ago

    Nope, I can't get a pic - the plant is still really small and I've tried getting close ups before and my camera basically sucks. But it looks just like splashes of cinnamon colored speckles mainly on the underside of the leaves. It's also on the one pitcher that's still on the plant... mainly sprinkled along one side. Pitcher production has also slowed down. And if I don't have to spray everything, like I said that would be a good thing!

  • petiolaris
    16 years ago
    last modified: 9 years ago

    If the problem is widespread, you could follow the advice given. but if it one or two leaves, you can just snip the affected leaves.

  • sakmeht
    Original Author
    16 years ago
    last modified: 9 years ago

    Thanks everyone for your thoughts... went ahead and sprayed just that plant, and will do a follow up spray in another 7 to 10 days. :)

0
Sponsored
Land & Water Design
Average rating: 4.9 out of 5 stars30 Reviews
VA's Modern & Intentional Outdoor Living Spaces | 16x Best of Houzz