Combatting Fungus Problems on Fruit trees

Today we present another article in our non-fiction writing contest – By Kate in GA

While this technique will work with all perennial plants, my focus for this article is really on the perennials in the garden. I will specifically talk about fruit trees. However, this will work on all perennial plants that may be giving you problems.

Let me start by saying that I have never seen this technique mentioned in any book or anywhere on the web. If you ask a master gardener in your county, they will probably say they never heard of it – and may even add that too much fertilizer can be harmful. However, I can honestly say this technique does work, and with more success than I ever imagined. This technique has come from my own personal experience and has managed to let my apple trees live less than 20 feet from my (and my neighbor’s) evergreen trees. All trees are playing well together and are happy.

Let’s start with a comparison in the human vitamin world. The government gives us minimum daily values for nearly all vitamins. However, manufacturing companies sell vitamins in much higher doses then the minimum recommend by the government because taking the higher amount makes people feel better. Vitamin E comes to mind for me. I take 400 mg every day because it helps me with pain but the government states the daily value needed is only 15 – 30 mg. (Not sure these numbers are correct, I looked up the daily value stat up on the web and found many different values. I combined them all in the range I displayed here.)

The same holds true for your plants. I first learned of this fact when we moved to our house 16 years ago. After the first year, I noticed that my grass always had fungus problems, but my neighbors didn’t. (Mostly I had dollar spot and fairy rings.) I just wanted my yard to look like my neighbors (also required by my HOA or I would have been fined). I put down all kinds of fungicide that I purchased in the home improvement centers. They worked for a short time, but the problem always came back. So I had my soil tested. I found out that I had no phosphorus and very little pot ash (potassium) in my soil. I did know that my neighborhood used to be a farm. I believe that my plot probably had the chicken house on it. Keeping chickens in one spot for many years will drain the phosphorus from the soil. I went to the local feed and seed store and purchased two fertilizers: one 50lb. bag of 0-45-0 and one 50lb. bag of 0-0-60. I spread both (in both the front and back yard) and two weeks later, my lot looked like the rest of the neighborhood! And it stayed that way for 2 years.

My neighborhood has changed quite a bit in the years I have lived here. We have quite a few Leyland Cyprus trees on our property, as well as Arborvitae Emerald Green trees. My neighbors have them as well. Both of these trees carry the Cedar Apple Rust fungus as well as many others. I got the evergreen trees long before I got the apple trees. Knowing that I might have problems with fungus on the apple trees, we planted three trees anyway. I thought that with a spray management program, I could make it work.

My apple trees are now in their 5th year at our house. We bought two year old trees, so I am guessing at the end of this summer, they will be 7 years old. It has not always been an easy co-existence for my apple trees & evergreens. The apple trees told me the second year they were here that they didn’t like living at my house and showed me that by picking up both Cedar Apple Rust and Fire Blight.

I thought, no problem, I will spray! Well, spraying didn’t work! It worked when sprayed right after a rain storm, but the dew is so heavy here in the summer, that each morning I got up I had more fire blight! That year, I cut off so many dead branches I thought I was going to lose the trees. We managed to scrape by that year, but I didn’t know if we should pull the trees and forget about growing apples or not. We decided to keep the trees and I thought I would try again in year number 3. I followed the spray recommendations from the University of Georgia and thought that would make the difference. Nope, it didn’t! After a lot of rain in April and May, I thought my trees would die.

While out and about one day in mid- May, I pulled into my driveway and noticed that I had dollar spot on my lawn. I looked at my neighbor’s yards and they did not have dollar spot. I thought, “Has it been 2 ears since I put down phosphorus?” I called up my feed and seed store to order more. Then I thought, if this works for grass, would it work for my apple trees as well? I ordered 100lbs. of 0-45-0 and 0-0-60 that year. I put 50lbs. out for the grass, (spread in both the front and back yard) and then put the other 50lbs. of each concentrating on the 1/6 acre were my trees were located (the trees are in my backyard and also got some of the initial 50lbs. that I put down for the grass.) I added it a bit heavy to the drip line but spread the rest evenly over the 1/6 acre. I watered it in immediately. I had to use a drip line because the sprinkler would have caused more fire blight on the trees. 1 week later, the episodes of fire blight and new evidence of cedar apple rust stopped!

This has now been made part of the routine care of my apple trees! I add one 50lb. bag of 0-45-0 and one 50lb. bag of 0-0-60 to the 1/6 acre were my trees are located each year. And, as I mentioned earlier, they are now almost 7 years old and much happier trees. I still used an integrated spray management program, but my emphasis concentrates on the early sprays needed in the spring. I only spray for fungus now about every 4 – 6 weeks during the summer months and apply the spray with a focus on the new growth. It is a bit of a challenge to know when to spray because the fungicide can damage the trees if it is over 90 degrees when you spray. (That is all summer long for me!) So I try to time it with a rain storm so the temps are lower. This is something I am willing to accept for the blessing of having my own apples.

I should also state that the phosphorus and pot ash fertilizers will not stop all incidences of fungus problems with the trees. However, it so greatly reduces the number of times fungus appears as well as greatly reducing the severity of the problem that I now find it completely manageable. I have only had to cut off a few small branches from fire blight on my apple trees this year. And, it has been over 3 years since I have even seen evidence of cedar apple rust. (I do understand that Cedar Apple Rust is a bi-annual problem, not an annual problem.)

Also, just so you know, I store this fertilizer so I always have 2 years’ worth on hand. When the world ends, I will still be able to manage my fungus problems with the apple trees for a while.

Now, if I can just get the squirrels to stop sampling the apples to see if they are ripe yet! I see covering those trees in netting in my future next year!

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  1. Something I use to treat fungus problems on plants like tomato plants and also used with a baby avocado tree I bought was to spray it with H2O2. Regular H2O2 from the store, put in a spray container. My landlord suggested it and it has sure worked. The plants had been so infected with fungus I was sure I would lose them and the avocado tree had infected a few other new plants, but after spraying with the H2O2 for a few days, everything was saved.

    • Gena,

      Personally I have never tried hydrogen peroxide on powdery mildew. I am going to try that the next time I get it on squash.

      I am not sure it would work on fruit trees because you would need so much – that isn’t sustainable in an end of the world situation.

      Thank you for your comment!

  2. PatrickM says:

    Good info to store. I have some old fruit trees on my property that I am attempting to rehab.

  3. mom of three says:

    We don’t seem to have problems like that but good to know for sure. After this year I’m finished with container gardening, it’s not worth it. I plan on re planting my elderberries, on our other property so they can branch out and live.

    • Mom of Three,

      Container gardening is hard work! I put all my tomatoes in containers. We don’t eat them fresh – we only make sauce with them. If I grow 30 plants, I can make enough sauce for 2 or 3 years. That way, I don’t have to grow them every year!

      I find putting the tomatoes in pots gives me more flexibility on how much sun they get – I can move them if needed. However, I agree with your thoughts on the matter, and I often ask myself is it really worth it.

  4. I’ve seen recommendations for rock dust for complete mineralization to help trees combat pests.

    • Mathew,

      I am not sure the rock dust will provide the phosphorus and pot ash in sufficient quantities to help fruit trees fight off the fungus problems we have in the south.

      The humidity here encourages fungus and mold to grow on everything. That include your house, sidewalks and driveways too! A wash every spring with bleach is needed to keep it all under control.

      • Yes, I lived in GA for a number of years, I remember. Still, even if you need some additional pot ash, and phosphorus, you usually also need other minerals. I think that’s the point of the rock dust.

  5. You need to watch this video if you really want your garden to just work without chemical fertilisers.

    Also you can make chilli tea to spray on the apples to keep pests and rodents (squirrels) away.

  6. Crazy Joe in South Jersey says:

    HELLO KATE IN GEORGIA , Bach’s Degree in Horticulture and Master Gardener thru Penn State – Go Lions .

    Most home owners or semi rural folk do not know or forget about fertilizing fruit bushes and trees , many just toss some lawn fertilizer there way and be done with it .

    Most do not consult the County Ag Agent . Even in high population areas there is almost always still a County Ag Agent or right next door in the adjacent county .

    I only recommend NEEMS OIL , I do not like chemicals .

    Also burning off around garden areas is good but most places will not allow it any more . Never met a disease or fungus that was fire proof .

    Most of the Master Gardeners I know have no background in Hort . , Arborculture or Botany , many are landscapers who try to learn more than weed whacking . Very few know what the Hortus is . Most MGs do not get into intense study after the 12 week or so program .

  7. Babycatcher says:

    How would you get netting above and around an apple tree that’s 15 feet high and 40 feet in circumference? Also, I’m thinking the squirrels would chew right thru the plastic. I am using hot pepper spray this year to protect my crop. Otherwise good article. Didn’t know about the connection between Leyland Cypress and cedar rust, but we live in an area that has large swaths of cedars, LC, pines and other conifers. I just accepted the presence of the cedar rust as a condition of living here. Now maybe it isn’t. Thanks! 🙂

    • Labgirl says:

      On a side note, I was told a couple of years ago that southern red cedar harbors stink bugs. I don’t know if this is true but I have lots of both.

      • Lab girl,

        I had never heard of this. You may want to spray those red cedars to help control the stink bugs. To me, that would be a better solution to having them ruin the garden.

    • Baby catcher,

      To net the trees, I expect I will need to purchase four nets and sew them together with fishing line. I have a ladder that is 25 feet tall so I don’t expect getting the netting on them to be a problem. I may end up doing one with netting and use chili pepper spray on the other two and see which is more effective.

      • Forgot to add that the squirrels don’t chew through the netting on my blueberries. Also, I have a friend who nets her cherry trees and the squirrels stay out of those as well.

  8. Labgirl says:

    Thanks for the great article. I will definitely be looking for those fertilizers. My two apple trees have had a rough year. A bad case of fungus and then something ate all the leaves off. I think apples are the hardest fruit tree to grow here.

  9. PlantLady says:

    Excellent article, Kate!
    Prevention is easier than curing. If fruit production is important to you, get rid of the alternate host plants! Sure, they may be “nice” plants/trees…but can you eat them? Surely you could find far better replacements that would also produce foods for you…other fruit trees or nut trees?
    That said – One of the easiest ways to prevent fungal problems on trees and plants is to properly prune, allowing excellent air circulation and sun penetration through the canopy.
    After reading hundreds of books on growing fruits and orcharding (most college-level) – and still not having a good idea how best to grow fruit – finally found Michael Phillips awesome book “The Holistic Orchard”. What a treasure! Now I know how to grow and prune properly. He said the best advice he ever got on pruning said that you should be able to throw a cow through the canopy of a tree, without hurting the cow or the tree (hehe). Basically, you want to end up with fruit trees that look like great big bonsai, with carefully sited branches to allow excellent air circulation and sun penetration into the center of the canopy. This book is one of those MUST HAVE references to keep on hand.
    I have nearly 50 assorted fruit trees now, and do no spraying, not even those Mr. Phillips recommends (all natural but not sustainable in our area). I keep the trees well-fed with composted manure and leafmould and place the chicken tractors under/around the trees at strategic times of insect pressure…seems to be working (so far, fingers crossed).

    • Hey PlantLady
      This video was so inspirational on how to do things naturally – called “Back to Eden”. I am sure you will enjoy it and find may useful suggestions in it.

      not affiliated not even on the same “hemisphere” 🙂

      • PlantLady says:

        CraigB: Thank you for the recommendation. That is somewhat how I have been doing things for about 35 years now! Right now I am mulching the beds with straw run through our chipper/shredder and using plain straw on the paths…because our wonderful neighbor has a huge old barn full of old straw she doesn’t need and wants out of there – so its free! I used to use wood chips on the paths, just laying down a new layer each year. Then every 3-4 years would rake the “whole” chips on top to the side then rake the composted chips up onto the raised beds. Do the same thing with the straw in the paths now. And used leafmould as a mulch on the beds…both the leafmould and chopped straw just sort of melt into the soil over the course of a season.
        It is all about getting organic material of any sort, whether wood chips, straw, leafmould, composted manures or yard debris, etc. into your growing area. Except for hay – don’t use hay or you will just be planting a hayfield! The soil’s organisms need that organic material to break down into their (and your plants’) food. When you feed your plants, whether organic or not, you are actually feeding these organisms, who break it down into a form your plants can actually use. Pretty much how the organisms in our gut break down the foods we eat into forms usable by our system.
        I notice they talk about using cardboard or paper to block weeds…I would never do that. The papermaking process uses lots of noxious chemicals, glues/binders and finishes…won’t put that crap in my gardens.
        I do use a lot of composted manures from my 25 chickens and 5 dairy goats…and a neighbor’s organic dairy herd. I never have enough manure – it is like black gold! My suburban-raised husband was amazed to discover years ago that my most favorite present for any occasion isn’t jewels or vacations or fancy do-dads…it is a heaping truckload of sh!t (hehe). Gene Logsdon’s amazing book “Holy Shit: Managing Manure to Save Mankind” is a must-have-on-the-shelf book for anyone who hopes to garden.
        My “secret” to great gardening is leafmould – it is the most amazing thing you can add to your garden, especially when you mix it 50/50 with composted manure. Leafmould is just chopped leaves left to compost into rich black fluffy stuff that does wonders for soil building. We have 19 acres of rich forest, with roads and paths through it, and harvest the leaves and small branches from the roads and paths to run through our big Troy-Bilt chipper/shredder.
        I use all raised beds. When I form the beds, I lay out the beds and paths, then remove the topsoil from the paths and put that on the bed areas…no sense letting good topsoil go to waste – it takes nature 100 years to form one inch of topsoil. And without any (or much) topsoil in the paths, you lessen the chances of weeds in the paths. Then I add about 8″ each of leafmould and composted manure and work it in well…to get the organic material down where it can do some good. And try to put a couple inches of good natural soil from our forest in the mix, to sort of inoculate it with the good organisms I want to get things working well.
        Rich living soil is your first – and best – defense against disease and insect infestations. If you have rich, living soil for your plants and trees to grow in, they are far better able to resist problems. Prevention is much easier than trying to cure something.

        • PlantLady… you need to be appointed the minister of agriculture and also medicine… So few people have any clue as to what you have just said. Most people think a handful of chemicals is what is needed when this is 2% of what is going on. Living soil… how many farmers or those in agri have a hint as to what that means? We have been fixing our gut with EM / probiotics instead of throwing vitamins etc down our guts the last while. The nuke it with poison then try fix it with chemicals is so 70’s but people dont want to change!

          Well done for such an informative and great post 🙂
          One can only pray that the likes of MonSatanO die from their own poisons and we can all move towards a living soil and food from a living soil again.

          ps We are living in the concrete jungle in Cape Town (South Africa) just dreaming of being on a farm. Grew up with many farms in the family though. Your situation sounds great!

          • ps the thing which I found from the video and then researched which is against raking / tilling is that you break the mycorrhizae up and they are then less beneficial. Their strands grow longer and longer collecting nutrients bringing them to the roots.

          • PlantLady says:

            CraigB: Aw, shucks…thanks! Except for threatening me with a gov’t position – no thank you very much! (hehe)
            You sound like you know what is going on…you HAVE to get out of that concrete jungle – FAST! Quick as you can, cause everything in this world seems to be hanging from a rotting, quickly unraveling thread. Trust me, you will love it once you make your escape. If at all possible, settle near where your family has farms – in the coming Darker Ages those around you will be of prime importance, because no matter how hard we try, we need others we trust implicitly to help us do all we will need to do. And you need time, lots and lots of time to get yourself set up in a sustainable manner before that last thread of “current normal” snaps.
            Heck, I am worried I don’t have enough time left to get everything I want set up and in place…and we are lucky enough to have paid-off lush land, a couple streams and ponds, mature and young fruit trees, nut trees, berry plants, grapes, hops (with all the equipment for a complete brewery and winemaking), ever-expanding garden areas, chickens, dairy goats (and hogs next year, god willing), woodstove and big wood cookstove with 27 gal. hot water reservoir, 3 wells (1 artesian), 2 EMTs, a midwife, a blacksmith and a Wizard who can fix anything with found objects…plus tons of books to hold the knowledge I can’t squeeze into my brain and most all the equipment needed to run this place (still need a couple broadforks).
            And while it is best not to till, I have hubby tilling up fresh ground to expand the growing areas pretty regularly…I don’t want to have to clear it with a shovel after things get tricky. Sometimes you have to take the less perfect path to get where you need to go in a hurry. We don’t till after the beds are formed and enriched. The beds aren’t surrounded by anything, just raked up.
            Please, get out while you can…any start you can make now will be so much easier than waiting until later. At least bank lots and lots of seeds and garden equipment. Don’t buy those high-priced “survival” seed banks…you can get far more of what you really need far cheaper by shopping around.

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