Some friends have asked that I write a column about pest control using common household products or so called “Home Remedies”. I have resisted doing this as we are taught in “Master Gardener” classes to only recommend garden solutions using “research based information”. Many of the “home remedies” that use materials found around the house have not been tested. Some do work but nobody has taken the time to research them to see if they are safe. The federal pesticide act requires that any product that claims to be a pesticide must undergo extensive testing and periodic retesting. It also requires that the active ingredient be listed on the label along with the plants it can be used on, what insect or disease it will control, and if used in the vegetable garden, how long between application and harvest. The testing does not guarantee that the product works as claimed, only that it is safe when used as directed. A home remedy does not have that testing. So how long do you wait before you can eat the produce? Or how often do you apply it and at what intervals? Remember that a “home remedy” control may be toxic to you, your plants and/or your soil. Use with caution.

          Part I talked about “Creepy Crawlies” (Insect and Animal Control). Part III will deal with “Weed Control”.

FUNGICIDES: “Rots and Spots” are not a pleasant site in the garden. The Lincoln Rose Society and Iowa State University recommends the use of “baking soda” for the control of black spot on roses. Mix 3 to 4 teaspoons of baking soda and 1 to 2 tablespoons of a light or “All Seasons” horticultural oil in one gallon of water. Spray the rose bush thoroughly (top and underside of all leaves, and the stems) once a week during the growing season with this solution. Do not use “dormant horticultural oil” as it is too heavy. Also, I have heard that soy or corn based cooking oil will work in place of horticultural oil. Try this solution to help control powdery mildew on some of your plants.

Last year I had a call from someone who wanted to use “bleach” as a fungicide, and a few months ago a man told me he used bleach to try and control “moss”. Yes, bleach will kill fungus and many other organisms. A 10% solution of bleach (one cup of bleach to 9 cups of water) works fine as a good disinfectant for pruners, pots, saucers, potting benches, etc. When dividing and transplanting iris, soak the rhizomes for not more than an hour or two in a 10% solution of bleach for disease control and to drown any borers or insects.

For bleach to be effective on plants and grasses in the yard or garden, it has to be at a strength that will also kill the grass, the treated plants or shrubs, and any beneficial organisms in the soil. Use bleach with caution.

CHLOROSIS: Most “Pin Oak” trees, some “Birch” trees and some other trees and shrubs get iron and/or manganese chlorosis. Some have suggested as a home remedy for chlorosis the pounding of a nail or nails into the tree and letting it rust in order to add iron. This  does not work as it takes a long time for the nail to rust and even then the iron is not in a form that the tree can use. The nail only damages the tree. Iron can be added in other ways such as with a spray of liquid iron, an injection of iron into the trunk with inserts, or the application of iron by a tree professional.

The symptoms of chlorosis include yellow looking leaves with darker green veins. There is usually iron and manganese in the soil. But when the pH of the soil is above 6.0, the ability of a plant to take up iron begins to diminish. The pH of most soils in Southeast and South Central Nebraska are between 6.5 and 7.0. Lime increases the pH of your soil. Therefore, never add lime to your lawn or garden unless a soil sample recommends it. Sulfur lowers the pH.

Blue “Hydrangeas”, “Rhododendrons”, and “Azaleas” also like soils that have a pH of 5.0 to 5.5. I like to use the granular sulfur to lower the pH rather than use aluminum sulfate as some plants do not like the aluminum. The granular sulfur I use is 90% elemental sulfur. Sprinkle the granular sulfur around the tree or plant in the spring and in the fall following label directions. Or use a bulb planter on your drill and make holes a foot outside and a foot inside the drip line and put sulfur in the holes. I use Holly Tone in the spring as a fertilizer and application of sulfur. Holly Tone is good for the plants listed above and contains 5% granular sulfur. Miracid and other water soluble liquid fertilizers are very weak in sulfur and thus I feel do not work as well as the granular products. They are good for fertilizing the plants but weak in changing the pH. Check with your full service garden center or your local County Extension Educator for help.

FERTILIZERS: As mentioned above, magnesium is one of the micronutrients that is needed in a very small quantity by most plants. If your plant fertilizer does not contain micronutrients, your plants can become deficient. Tomatoes, Roses, and Clematis have been found to benefit from 2 to 3 Tablespoons of Epsom Salts (Magnesium sulfate) around each plant once a year.  Magnesium also helps free up the iron in the soil so a plant is able to use it more effectively. Magnesium does not lower the pH like sulfur.

          The best “Home Remedy” type of fertilizer is your compost pile. Make your own fertilizer by starting a compost pile. Your local County Cooperative Extension office has a good NebGuide on composting or go to the internet. Compost adds organic matter to hard clay soil and provides many micronutrients. This is one of the best fertilizers you can use. 

reminder: Some “home remedies” passed on from your grandparents may work, but be careful. Remember, they have not been tested. As a result you do not know if the product is safe to use on the plant you are trying to treat, or what the long term effect will be on the environment. Whether you use a home remedy or a commercial product, use it correctly and follow the directions on the label. If the recipe calls for two ounces per gallon of water, four ounces is not better. Misuse of any pesticide can be unhealthy for you and your family, whether it be one you purchased or a “home remedy”. Read the label before using a product, not after!!! Then be sure and follow the instructions on the label as to what plant the product can be used on, how to prepare the product, and how much to use on the plant, shrub, flower, or tree you need to treat. Do not over medicate your plants or your soil!!!!! 

          If in doubt, contact your local County Cooperative Extension Educator for information or check the internet at “http://ianrhome.unl.edu/search”. In the top box scroll down to Extension publications. In the bottom box type in the name of the plant, shrub, flower, tree, insect, or disease you want information about or you want to treat or control. A list of publications will appear. Read the ones of interest and print what you want to file and save.

          Iowa State University Extension information may be reached at www.ipm.iastate.edu/ipm/hortnews. In the search box type in the name of the plant, shrub, flower, tree, insect, or disease you want information about or you want to treat or control. A list of short, practical articles will appear. Read the ones of interest and print what you want to file and save.

          In Part III  I will cover “Weed Control”.

Copyright Aug. 13, 20005