Soil Damage?

Discussion in 'Soils, Fertilizers and Composting' started by lily, Aug 14, 2003.

  1. lily

    lily Active Member 10 Years

    Messages:
    366
    Likes Received:
    0
    Location:
    Abbotsford, British Columbia
    For a new gardener, I must say that gardening for me this summer has really been a challenge! I almost gave up a couple of times out of "fungus gnat" frustration but I am really enjoying gardening. Because of the severe fungus gnat problem and trying everything from insecticidal soaps to maliathon - I'm sure my plants have taken a bit of a toll to say the least. As a result of using so many different kinds of insect killers, I'm wondering about my soil? Do you think I should I go out and purchase fresh soil and transplant all my plants into new/clean soil? If so, what kind?

    My hibiscus was also affected with gnats. I don't see any gnats in my hibiscus now but I'm concerned about any larvae that might still be in the soil and I'm afraid to bring my hibiscus into my apartment when the nights get colder.

    I also noticed even after giving my Martha Washington (as with all my other plants) two (Malathion 50) treatments, 7 days apart, there are still gnats in that one pot, although the blooms and foilage are still quite beautiful.

    I used the Maliathon 50 with the recommendation of a "qualified" nursery staff person at our garden centre. After I used it on everything, I looked it up on Google and almost fainted when I found out that they use Maliathon for West Nile Virus to kill mosquitos. Okay, I guess I should have looked it up before I used it but I figured she knew what she was doing. I noticed in some of my pots some little tiny pea like shells, do you think these are could be eggs? "I cringe at the thought of them"

    I'd appreciate any suggestions you might have for me now regarding my soil. I'm wearing rubber gloves as I'm afraid to touch the soil as Malathion is poisonous. My garden is on my balcony, thank goodness there are no children or pets around.

    I can say this though...I've learned an awful lot about the do's and don'ts of gardening. I think the biggest and most important thing I've learned is to give my plants good drainage and don't overwater. I have definitely learned my lesson. Thanks sooooo much for all you help!
     
  2. jimmyq

    jimmyq Well-Known Member 10 Years

    Messages:
    2,345
    Likes Received:
    0
    Location:
    Metro Vancouver, BC, Canada.
    Malathion is definately poisonous, pretty much any product designed to kill something (ie. insects such as fungus gnats ) is going to be poisonous to some degree, thats why it kills things, ie. fungus gnats. I am not saying malathion was or is the best choice for your situation, and I don't think it is registered for fungus gnats to be honest (in BC a pesticide must be registered for each use or we aren't (as licensed dispensers) allowed to recommend it for the situation you may have). If the plants are outdoors in pots, a "broad spectrum general purpose" insecticide is the most logical choice (if one is has decided to use a pesticide). Your choices would be Diazinon, Malathion, Sevin and Methoxychlor for use as a soil drench to try to eliminate fungus gnats. Reducing your watering intervals is much more effective in helping eliminate and prevent them. Another thing that helps is to empty the drainage saucer regularly if the plant is equipped with one. Diatomaceous earth is a possible alternative that is very safe for use (for the person, not the fungus gnats) that should be available in most garden centers. I think my advice to you, since it sounds like you are very much not interested in using noxious chemical control is to make sure when you ask for a control method, tell the person you are asking what you are willing to use and what you are not interested in using. We will try to tell you the most effective control measure, not necessarily the most environmentally friendly or safest method, they usually arent the same thing. Hopefully you gain control over these beasts soon with minimal additional hassle. :)

    the tiny little pea like shells are most likely the casings for Osmocote, a common nursery fertilizer used on tropical plants. They are a polymer coating applied to fertilizer mixture that breaks down slowly to feed the plant.

    feel free to don the rubber mittens when working in soil recently treated with a pesticide, even if its labelled as totally safe its not going to hurt anything to be extra safe, you never know what we will find out about some of these common chemicals down the road. If you r plants are small or young, I would possibly consider replaceing them totally rather than trying to replace their soil. If you are transplanting, try using some earthworm castings ( about 10%)and feel free to increase the perlite content of your soil, I have used a 50 / 50 mix of perlite to packaged garden soil and it worked great, you just have to make sure to monitor your soil moisture as it dries out quick in hot weather. Water infrequently and deeply rather than shallow and often, its the best way to leach things out of your soil and keep the moisture level to an optimum level. I water most of my houseplants about once a week or so at this time of year and maybe once every two to two and a half weeks in the winter. Outside the containers get checked daily and watered maybe every third or fourth day.
     
  3. lily

    lily Active Member 10 Years

    Messages:
    366
    Likes Received:
    0
    Location:
    Abbotsford, British Columbia
    Soil Damage

    Hi Jimmy,
    Thanks sooooo much for taking the time to explain everything to me. I've printed out your suggestions and will follow them carefully. Today, I purchased some bonemeal for my roses, chrysanthemum and clematis. I also purchased perlite as you suggested. Should I dig about 50percent of the soil out of the pot and replace it with perlite and mix it up? I'm not sure how to do this or how much bone meal to put in a container - Thanks Jimmy.

    BTW - NO MORE GNATS! I'm so very pleased they're gone. I've started my new watering regime. Once a week, I water deeply - that's it!
     
    Last edited: Aug 19, 2003
  4. jimmyq

    jimmyq Well-Known Member 10 Years

    Messages:
    2,345
    Likes Received:
    0
    Location:
    Metro Vancouver, BC, Canada.
    If you want to try to add perlite to the existing soil just gently work at the top part of the pots, if the soil comes away easily, try mixing a 50/50 perlite and potting soil blend and add it as a top dress of sorts. If you are transplanting, use the 50/50 mix in the pots as the new soil and you should find exellent drainage and hopefully gno gnats. :)
     
  5. lily

    lily Active Member 10 Years

    Messages:
    366
    Likes Received:
    0
    Location:
    Abbotsford, British Columbia
    Perlite

    Hi Jimmy,
    I did what you suggested. Added the perlite and I can really see and feel the difference in the soil. It's really light and doesn't compact in my containers. Thanks for telling me about this. I don't think I will ever plant anything without using some perlite.
     
  6. jimmyq

    jimmyq Well-Known Member 10 Years

    Messages:
    2,345
    Likes Received:
    0
    Location:
    Metro Vancouver, BC, Canada.
    groovy. happy to hear it has helped a bit.
     

Share This Page