I would like to make my own dormancy oil spray for this year. I would be spraying about 1500 trees with a 100 gallon air blast sprayer. I see a common recipe being:
I would have to make this mix probably 3 times annually. Given the quantity of trees, is there an effective and cost conscience recipe? Can you use used cooking oil if it is filtered? Any thoughts would be great.
I am using 3 Tablespoons Canola oil and 1 tablespoon of dawn dish soap to a gallon of water with good results.
I have seen this in a few posts and books and being new, if you donât mind I have a few questions -
What is the benefit of spraying trees with oil?
Do you spray the entire tree or just the lower portion of the trunk?
I assume the dish soap helps the mixture to âstickâ?
Should this be done more than once per year?
Are there certain species this practice benefits most (pears, apples, peaches, cherries, pawpaws, persimmons etc) and are there any that do NOT need sprayed?
I apologize for commandeering the thread but Iâve been meaning to ask about the oil thing for a while and kept forgetting.
I can answer the first questionâŚ
Spraying with oil helps to smother insects and their eggs. I use a lime/Sulfur oil which also supposedly helps with fungal issues as well.
I have always wondered about some of your other questions myself. Especially if there is a benefit in doing it more than once during the dormant season (iâm trying to fight a nasty cottony peach scale infection and my plan this winter was a couple sprays⌠At least once following leaf-fall, which I did, and another before leaves start pushing in the spring).
Scott
To my knowledge, the oil suffocates insects that have overwintered in the tree. This needs to be done before bud break when there are no leaves or flowers. It should be put on all tree wood. As I understand it, the soap acts as an emulsifier to help make the oil âmixâ better than it would otherwise with straight water. I have heard that it is to sprayed on most any fruit tree. Here in southern Wisconsin, we do it at the end of February at the earliest and through the first three weeks of March up to bud break. It will get washed off by rain, snow, etc., but it does help.
@disc4tw I just took the liberty of flagging your post to get a moderator to move it to its own thread. Youâve raised important questions that deserve to be their own. Iâm glad you brought them up.
My guess is that it would be almost as expensive to buy vegetable oil to make the mix as opposed to buying a commercial product. I believe I paid less than $70 for 5 gallons jug of horticultural oil but its less expensive in larger quantities like 50 gallon. It was made from mineral oil rather than vegetable oil but I know ORMI versions are available.
I think anyone can continue a topic in a new post ⌠just click on the little âlinkâ below the post to make a new post referencing the one you clicked on the link.
Thanks, Scott. I gave it a try and it seems to have worked.
Since we donât know where the critters are laying in wait,yes,the whole tree is sprayed.
Because water and oil donât mix too well,the soap helps to mingle the two together.
It depends on the problems.I usually do it during late Winter or early Spring,just before bloom,to combat Curly Leaf Aphids in my Plum trees.
Hmm,I didnât know how to bring the quote to your new thread,Mark.
Me neither! I guess we just go with what we have and call it good, try again some other time. Itâs a good thread either way.
Back to the topic on hand- I know there have been many a hippy who have recycled old fry pan oil from burger joints and filtered it as biodiesel for their vehicles. Iâm sure that if you can run an engine on it that it would be perfectly fine for a tree spray as long as the residual particle size wouldnât clog your spray gun. You just might get a hankering for McDonaldâs in the process.
I found some scale on a few indoor citrus, did not have a horticultural oil on hand so I used about a teaspoon of canola oil and a dash of soap per qt. As a spray.
I did this about a week ago . Scale seams to be dead , rubs off easily.
The whole plant is very shiny looking , a heavy oil coat.
No apararent damage from oil to leafs .
Before I treat the rest of my plants , I thought I would ask if anyone has had any damage from using canola oil sprays. ?
Fry grease from fast food restaurants would clog a spray gun in seconds. It is probably impossible to tell if it is safe to use until after your trees are dead.
I spray dormant oil only once per season following Alanâs spray guide.
I donât see any reason to use anything other than horticultural oil of some kind because it is cheap and only needs to be sprayed once or at most twice per year at least in my location. It is even cheaper when bought in large quantities.
I used canola oil this year for my pears because I had some very much expired oil that I have been trying to get rid of. It seems to have done the trick with some soap and water mixed. I saw the idea on Scottâs spray guide.
It appears horticulture is a mineral oil based product. I wonder if plain old mineral oil would be as effectiveâŚ
I am not sure why anyone would do that since plain mineral oil costs slightly more than all season horticultural oil.
Found this label , a 96 % canola oil for making a 2% diluted spray.
Canola is cheep at the store.
Canola corn and soy oils are all good and the sources for the organic oil treatments usually higher clarity the better for your sprayer