What Is Dormant Oil?
Dormant oil is a type of chemical used for various purposes such as cleaning products, paints, solvents, pesticides and other industrial uses. It is produced from petroleum or natural gas.
The main use of it is in the production of certain types of plastics such as polyethylene terephthalate (PET) which are commonly found in food containers. It is also used in the manufacture of some paper products.
It is classified as a hazardous waste because it contains toxic chemicals and heavy metals that may leach into groundwater if not properly disposed of. There have been reports of cancer in workers exposed to it at one time or another.
Why Use Dormant Oil For Fruit Trees?
There are several reasons why you might want to use dormant oil for your fruit tree. You could spray it on the branches so they don’t rot off easily. Or you could spray it around the base of the trunk where there is no air circulation and rotting would occur most quickly. If you live in a dry climate, then this method will provide relief from summer heat and drought conditions.
Mostly, dormant oil is used as a dormant spray for fruit trees. If you live in an area that has a dry season, then the oils help seal the tree cuticles to prevent water loss. This is necessary for young trees that are less than six years old and still developing their root system.
How Do You Make Dormant Oil?
You can make your own dormant oil by combining 1 gallon of light cooking oil with 2 cups of diesel or kerosene. It is a simple process that most people can do at home. You just mix the ingredients in a container and then let it set for about a week. Then you strain the mixture through cheesecloth to remove any impurities and pour it into a spray bottle for easy application.
You can also make a stronger mixture by combining 2 gallons of light cooking oil, 4 quarts of kerosene or diesel, and 1 pint of gasoline. This makes about 5 gallons of dormant oil. This is suitable for larger projects such as treating large trees or your entire orchard.
How To Use The Dormant Oil?
Before you apply the solution to your trees, you need to make sure that the soil is moist but not wet. A good way to do this is to wait a day after an expected rainfall. You don’t want the roots soaking because this can promote disease and rot.
Using a garden sprayer, apply the mixture thoroughly on the base of the tree, the lower trunks, and the branches on the lower third of the tree. It is not necessary to soak the soil but you do need to make sure that you get all of the lower limbs and the base of the tree.
Spray any exposed roots as well. Remember that this is a dormant solution so it is not likely to cause any damage to the tree or its fruit unless you apply too much. You can always do successive sprays if needed.
How Often Should You Spray Dormant Oil?
Most people choose to do two or three treatments during winter, spaced out by about a month. This will help to ensure protection for the tree during the dry season. However, this is not usually necessary for trees that are planted in moist soil or if you live in a region with high rainfall.
What Are The Benefits Of Dormant Oil?
The most obvious advantage is that it protects your trees from moisture loss during dry periods. This can increase their life span and prevent sunburn, allowing them to produce more fruit over the years. It also prevents weak spots from forming on the outside of the tree.
This can prevent dangerous situations where animals or even people can get their heads stuck between the bark and the wood because it has dried and shrunk. By preventing moisture loss, insects are less likely to infest the trees as well.
Dormant oil will not protect the inside of your tree from rot if it is already infected. It is only a preventative measure. Also, it isn’t effective on all types of trees and may cause damage to others, so you should always test a small area first before applying to the entire tree.
You should also never spray the solution on citrus trees unless you want to kill them! Finally, it is only effective for two or three months during the winter. After that time, the effects wear off and you will need to reapply.
Is Dormant Oil More Or Less Effective Than Tree Wrap?
Tree wrap is an alternative way to protect your fruit trees from moisture loss. The process is very similar but instead, you tightly wrap a tape around the tree several times. This keeps the bark from expanding and contracting with the weather, thus preventing moisture loss.
The upside to using tree wrap is that it can be left on the tree for years at a time.
Sources & references used in this article:
Using oils as pesticides by CE Bogran, S Ludwig, B Metz – Texas FARMER …, 2006 – oaktrust.library.tamu.edu
Effect of rootstock and treatment date on the response of pistachio to dormant applied horticultural mineral oil by RH Beede, L Ferguson – III International Symposium on Pistachios and …, 2001 – actahort.org
Growth stages in fruit trees-from dormant to fruit set by P Chapman, G Catlin – 1976 – ecommons.cornell.edu
Populations of the European red mite as affected by spray schedules by CR Cutright – Journal of Economic Entomology, 1944 – academic.oup.com
Horticultural oils by WT Johnson – Journal of Environmental Horticulture, 1985 – meridian.allenpress.com
A decade of pest control in British Columbia orchards by AM Burroughs – Amer. Soc. Hort. Sci. Proc. 20, 1923