Thinning a prolifically producing peach and pleading for problem resolution of peach leaf curl

Hi Y'all,

Two years ago a volunteer peach tree (transplanted from compost in our garden about 5 years before) blossomed for the first time and produced a super abundant crop of delicious Elberta peaches.  Last year it produced only 2 dozen blossoms and we harvested 7 peaches!  (Lost the rest to hail!)

This spring it bloomed profusely and it seems that every blossom was pollinated and hundreds of little peaches are developing.

I knew the tree could not survive the load nor would the fruit be very big if we left them all on the tree. So this weekend I did a massive thinning job (the aim of which was to have a space of 4" between peaches. That meant removing 950 (yes nearly a thousand) small peaches!  I actually counted them.  (See the pic below.)

But, this year our peach leaf curl problem is greater than ever before!  I've inspected many of the affected leaves and see no evidence that it is insect related. No bugs, no eggs, no '"tents", no holes etc. (see a couple of pics)

Does anyone know what the cause is of these curled, deformed and thickened leaves?  Any effective cure must take into account the actual cause (at least to my way of thinking!)

IN previous years, I removed all the affected leaves as I saw them (in case the thing could "spread" from affected leaves to unaffected ones. But I don't know whether that did any good or not. So I am asking for help from those who know what the cause is.   Am I wrong and is it an insect plague? If so, what is the insect and how does it perpetuate?   Is it an airborne blight?  If so, what can be done to restrict it or reduce its effect?  Does anyone know of any studies on peach leaf curl? And can anyone tell of an effective remedy which prevents, reduces or restricts its affect on peach trees?

Can you post a picture of the base of the tree, sometimes that can help figure it out!?

You might try this.  Don't know if this works or not but I went by it a few weeks ago.  It is a compost tea solution suggestion.  

Peach leaf curl disease is caused by the fungus Taphrina deformans, it is recuring once the fungus gets attached to the bark of the tree.
The peach leaf curl pathogen also infects young green twigs and shoots.
Affected shoots become thickened, stunted, distorted, and often die.
Only rarely do reddish, wrinkled to distorted (or hypertrophied) areas develop on fruit surfaces.
Later in the season these infected areas of fruit become corky and tend to crack.
If leaf curl infection builds up and is left uncontrolled for several years, the tree may decline and need to be removed.

There are fungicides that work quite well at eradicating this fungus;
copper sulfate is mixed with hydrated lime to make a Bordeaux mixture, the copper sulfate and calcium in the lime react together to form a fixed copper product that is effective against peach leaf curl.
Bordeaux mixture is not available for sale; it must be mixed up just before application, and the ingredients can be very difficult to find.

THE BORDEAUX FORMULA

Although there are many formulas for preparing Bordeaux mixture, generally a ratio of 10-10-100 works well for many disease-causing pathogens. The three hyphenated numbers represent the amount of each material to add.
The first number refers to pounds of copper sulfate, the second to pounds of dry hydrated lime, and the third to the total gallons of water. Thus a 10-10-100 Bordeaux mixture would be comprised of 10 pounds of copper sulfate, 10 pounds of lime, and 100 gallons of water.

A more manageable amount for the home gardener would be a 1-gallon mixture of 10-10-100 Bordeaux, which would contain 1/10th of a pound of each of the dry ingredients, which would be 3 1/3 tablespoons of copper sulfate and 10 tablespoons of dry hydrated lime in 1 gallon of water. You can purchase copper sulfate and hydrated lime at most garden centers.

THE MATERIALS

Copper Sulfate
Powdered copper sulfate, often referred to as “bluestone,” is a finely ground material that dissolves relatively quickly in warm water. Ordinary, lump copper sulfate isn’t satisfactory, because it is slow to mix into the solution. Store copper sulfate in a dry place. If it gets moist, it becomes lumpy and difficult to work with. Fixed copper fungicides shouldn’t be used in making up a Bordeaux mixture.

Lime
You can use either dry hydrated lime or slaked lime to prepare Bordeaux. The most important point is to use fresh lime. Don’t use lime from last season, and purchase only what you can use in the current season.

Hydrated Lime
Use only good quality hydrated lime (calcium hydroxide). The hydrated lime should be fresh and not carbonated by prolonged exposure to air. Hydrated lime is a dry product commonly used to make plaster and is readily available under several trade names. When mixing lime, protect your eyes, nose, and mouth by using a dust- and mist-filtering respirator.

Slaked Lime
Slaked lime is prepared by adding “quick” (hot, burned) lime (calcium oxide) to water to produce calcium hydroxide. Slaking quick lime in water can produce heat sufficient to boil the water, so regulate the amount of lime you add to the water at any one time, so the mixture doesn’t splash. Wear goggles or safety glasses to protect your eyes and stir the mix with a wooden stick while adding the lime to the water. The slaking chemical reaction takes 1/2 to 2 hours, so prepare the lime mixture before you plan to spray.

To make slaked lime add 1 pound of quick lime per gallon of water. This results in a mixture the consistency of milk. Slaked lime makes a superior suspension, but it requires more time, effort, and containers than prepared hydrated lime. If using slaked lime, follow the procedures in the Stock Solutions section below.

MAKING THE BORDEAUX MIXTURE

The effectiveness of a Bordeaux spray depends almost entirely on following the correct procedure for mixing. You can prepare Bordeaux directly in a spray tank equipped with an agitator, or if you don’t have a power sprayer, you can prepare smaller amounts for use in a hand sprayer. If you use a hand sprayer, you’ll first need to mix up stock solutions of lime and copper sulfate as described below. No matter how you mix the ingredients, you’ll need to use the spray solution soon after you prepare it, since the mixture will deteriorate upon standing.

When applying Bordeaux, be sure to wear protective clothing, including goggles, because the spray deposit is corrosive, can permanently stain clothing, and is difficult to wash off.

Dry Form

If both materials are still in dry form you’ll need to use a tank with an agitator. Follow these steps to make a tank mix of 10-10-100 formula. Use a ratio of 1 gallon of water, 3 1/3 tablespoons of copper sulfate, and 10 tablespoons of hydrated lime for each gallon of spray mixed.

Start flowing water into the spray tank. When you have put about 1/3 of the water into the tank and the mechanical agitator is in operation, start washing the copper sulfate into the tank through a screen with water from the supply hose. A wooden paddle is useful for working the copper sulfate through the screen. Don’t hurry it through the screen; give the copper sulfate time to get into solution in the tank. By the time 2/3 of the water is in the tank, all of the copper sulfate should be mixed in.

In a plastic bucket or other corrosion-resistant container, mix the dry hydrated lime into a portion of the remaining water. Then slowly pour the lime suspension into the copper sulfate and water mixture. Finish filling the tank to the correct volume of water. You can include the rinse water from the mixing container.

Continue agitating the tank while adding the ingredients and applying the spray. A bypass agitator system usually isn’t adequate for preparing a tank mix of Bordeaux.

Apply the Bordeaux the same day you prepare it. After you have used up the mixture, immediately rinse the equipment at least three times, since the mixture is highly corrosive to metal tanks and pump parts. Add a small amount of vinegar to the rinse water to neutralize any leftover residue.

Stock Solutions

The old-fashioned way of making a Bordeaux mixture is to prepare “stock” solutions of lime and copper sulfate that you later mix by pouring them into water in a sprayer. This method also works best for making small quantities of Bordeaux.

Using a plastic bucket, dissolve 1 pound of copper sulfate into 1 gallon of warm water. You can store this solution indefinitely in a stoppered, glass container.

For the lime, use the slaked lime suspension described above or mix a solution of 1 pound of fresh hydrated lime in 1 gallon of water. This mixture needs to stand for about 2 hours before use. You can store the lime mixture indefinitely as well in a stoppered container. Preparing a stock mixture of lime eliminates the need to obtain fresh hydrated lime each time you prepare a Bordeaux mixture.

Be sure to clearly label both stock solutions and store them where children can’t get into them, since these materials, especially the copper sulfate, are very toxic and corrosive.

To make 2 1/2 gallons of a 10-10-100 Bordeaux mixture, measure 2 gallons of water into a strong plastic bucket. Shake the copper sulfate solution vigorously before adding 1 quart of it to the 2 gallons of fresh water. Always add the copper to the spray water before adding the lime. Shake the lime mixture, and add 1 quart to the 2 gallons of water. Keep stirring the spray water mixture while adding the copper and the lime and continue stirring or shaking for several minutes before pouring it into the sprayer. The mixture now is ready to use.

Be sure to constantly shake the sprayer while using it to avoid clogging. Read the label directions carefully on the copper sulfate regarding the proper protective equipment to wear when preparing the stock solutions and when spraying. Bordeaux performs best if nothing is added to the prepared mix described above.

This formulation of Bordeaux mixture will be adequate for practically all home-garden, disease-protection needs. If you wish to maintain Bordeaux mixture on a tree throughout the entire winter rainy period, you can reapply the spray, or use a slightly stronger mixture—1 1/2 quarts of each stock solution to 2 gallons of water. In spring when buds are opening or on sensitive plants, use a slightly weaker mixture—1 pint of each solution to 2 gallons of water—or use a fixed copper spray.


That's the best "Standard Method" for controlling this fungus.
The best solution is to make an aerated compost tea from a highly active compost heap.
1 lb. of compost per 3 gal. of non chlorinated water, the compost is best contained in a cloth bag.
The tank for making the tea can be as simple as a large bucket with two long air stones and a high volume fish tank air pump or it can be a vortex setup.


Those are your best choices, I wish you great luck,

Redhawk

In the areas that I have lived California and Oregon, I have never had any luck getting rid of peach leaf curl once it occurs. Every year is worse than the last. I've had the best luck with buying naturally peach leaf curl resistant cultivars, easier in Oregon than California. Best of luck.

Bryant, how long does the compost tea need to aerate? Can I just stir with a stick multiple times a day, or do I need to use a air stone?

Stacy Witscher wrote:In the areas that I have lived California and Oregon, I have never had any luck getting rid of peach leaf curl once it occurs. Every year is worse than the last. I've had the best luck with buying naturally peach leaf curl resistant cultivars, easier in Oregon than California. Best of luck.

This was my worry about two of my trees. :( I have a peach and a nectarine that I got a few years ago and they have been riddled with leaf curl every year since. I'm actually kind of mad about it since I'm certain it was infected nursery stock and they were a lot more expensive than my other, less fancy peach trees, but I feel weird dumping them since they were a gift from my father-in-law. I tried liberally using a sulfur spray on the recommended schedule and it didn't seem to do anything at all.

I haven't seen any naturally resistant nectarines. The peach varieties that worked best in California was Indian Free and Frost. I have two peach trees here in Oregon that don't have peach leaf curl, and when I moved in one that did. I removed and destroyed that tree so as to not spread the disease (not sure that's the right word, but I think everyone knows what I mean). The more mature peach tree on the property is not labeled, I will check the other one tomorrow and let everyone know.

When all is said and done, my experience is that growing fruit ideally suited to one's area is always easiest. And in the western, Mediterranean climate peaches aren't really that.

As a homesteader (not a commercial grower), I try to rely primarily on low maintenance plants and then I have my pet projects that I'm willing to spend a little more time and effort on. We all have preferences and that's okay.

I've only had peach leaf curl when the leaves get wet.  An unseasonable rain shower or careless watering.  But most of the peach tree is under the overhang of the house so it misses the dew and rain.  I remove the curly leaves and the tree is fine.

If the tree got some good manure the fall prior, then it is less likely to get the curl.  

Most years it doesn't get any curl.  

Never knew what caused it before.  Neat stuff.  Thanks Bryant!  

We notice many local farmers have blue hands at certain times of thee year, all the vines are blue as are the potatoes. Even some stone houses are stained blue where vines grow up them and Bordeaux mivture has been used.  

Nicole Alderman wrote:Bryant, how long does the compost tea need to aerate? Can I just stir with a stick multiple times a day, or do I need to use a air stone?

Compost teas are best when aerated for 24 to 48 hours Kola.
Using a stick to stir it into a vortex works just fine around once every hour or two while you are awake will give you a good tea with active microorganisms.

I didn't mention it but I like to use 2 tbs. of black strap molasses in my tea batches, the amount of sugars is lower and that helps keep bad bacteria and other "nasties" from proliferating in your brewing tea while giving just enough food for the good guys we are making the tea for.

I have made pure manure teas in the past from well rotted cow and horse manures, these worked pretty well as a spray but were fantastic when used to water plants, no sugars were used in those teas and they were stirred with a paddle about 4 times a day for 2 or 3 days before I started using the tea.

Redhawk

Dr. Redhawk. Can you recommend the various ratios/recipes for your compost/manure tea mixes?  
I am never sure of when to use some of the recommendations from other sites.  
Use kelp or not?
What about the mix of horse feed molasses since it is easier and cheaper.
12 hours for bacterial and 24 for fungi mixes?

My compost teas start with the compost heap build.
I like to set up a heap that will contain most of the microorganisms I want for my soil so I layer the heaps with 4 to 8 inch starting layers.
I always begin at the soil level on a spot that has had a compost heap on it previously, this area has all the organisms in the soil from my previous activity of composting there.
My first layer is either straw or hay that isn't edible by the donkey, from there I lay down a 4 inch layer of donkey and hog poop, next is a 4 inch layer of chicken house cleanings (straw and poop mixed),
then I sprinkle some soil over the whole heap, this usually is about two point end shovels (slight mound not as much as you can hold on one), I sprinkle sea-90 over the heap from a ptarmigan cheese container, That is Layer one.
Now I repeat the layers until I have it 4 to 5 feet tall.
The next step is to water the heap, I use a garden rain wand to not disturb any of my work at building the heap, once the heap is weeping at the bottom I let it drain for about 20 minutes and then I cap it with soil about 1/2 inch thick and put an old carpet on top as a cover.
This will sit for 2 weeks and then I check with the thermometer for internal temp. If it is heating well I leave it alone, If it isn't heating I use a pitch fork to slide into the layers and lift them so more air can enter the heap, I also check the moisture level of the heap.
I rarely turn a heap, I now prefer to use the pitch fork to lift the layers instead and If I feel I need even more air inside the heap I will use my air compressor, a 3/4 inch pipe and a blow gun fitting to inject air to the bottom of the heap. (I have done this only twice, the pitch fork seems to do great)
My compost heaps normally take about 3 months to become nicely decomposed, crumbly and sweet smelling.

That is my compost for teas.
If you have kelp or other ingredients for compost making, great, use what you have or can get or want to use. When I do a pruning or cutting session I tend to make a heap with those ingredients for soil amendment more than tea making.

To make a compost tea I am now using a 25 gal. plastic barrel (mines blue and had a soda pop syrup in it previously), I am currently using air stones but I have plans to plumb it with an air injector pipe that will form the vortex mixing action when I have the time.
I have a big bunch of brand new grain sample sacks that hold 5 lbs. of wheat, I fill 2 of these, for a batch of compost tea, from my compost tea compost heap and hang them from the edge so they hang about 8 inches below the surface of the water. (I use 20 gallons of water per batch)
When I am going to brew a batch I fill the barrel two days before with our tap water and I toss in 1/4 cup of sea-90 and use a paddle to dissolve the sea-90 into the water.
The day the brewing is going to start I hook up the two air hoses from the 8 inch long air stones to a 150 gal tank sized air pump for aquariums and lay out the extension cord so I can plug in the air pump.
I fill and hang the bags into the water in the barrel and make sure they are water saturated so they will stay under the surface, I then turn on the air pump and place a piece of aluminium roofing material over the barrel.
I can now wait for up to three days (2 days is best) before I can use the tea. When I get ready to use a tea batch I take a sample vial of the tea for checking microbe counts and typing with the microscope.
When I spray I use a pump up pressure sprayer that holds 2 gal. I like the nozzle to be set for a wide stream not a mist. I also will use up the whole batch with in that 3 day time period. (good teas degrade as they age past three days)

Hope that helps you out Dennis.

Redhawk

addendum*
I have used a 10% sweet feed as an addition to my compost bags when making a tea so I don't see a problem with using it as a BSM replacement. I never brew for less than 24 hours and never more than 72 hours, but that's just what works best for me.

Stacy Witscher wrote: I tried liberally using a sulfur spray on the recommended schedule and it didn't seem to do anything at all.

hau Stacy, Most likely the sulfur spray was not the right type of sulfur spray and thus was not effective as you mention it not doing anything at all.

Bordeaux mixture works very well for eradicating the fungus Taphrina deformans, your best alternative is a good, aerated compost tea sprayed all over the tree and the surrounding soil. (this is working for fire blight on pears and apples too at my farm)

The other alternative is like others have mentioned, buying trees that have natural resistance to Taphrina deformans.

Redhawk

r ranson wrote:I've only had peach leaf curl when the leaves get wet.  An unseasonable rain shower or careless watering.  But most of the peach tree is under the overhang of the house so it misses the dew and rain.  I remove the curly leaves and the tree is fine.

If the tree got some good manure the fall prior, then it is less likely to get the curl.  

Most years it doesn't get any curl.  

Never knew what caused it before.  Neat stuff.  Thanks Bryant!  

R, you are so lucky to live in BC, the low humidity is one of your helpers when it comes to leaf curl as you have noticed. Good manure will contain microbes (several  actinomycetes (antibiotic producing bacterium) and other specialized bacteria.
These bacteria exert their antifungal activity through the production of extracellular lytic enzymes, and other compounds thought to be antifungal in nature are being studied now.
If you don't have or can't get Good Manure to make your tea with you can dissolve two probiotic capsules in a quart of warm water and add that to your brewing tea, this will give you a good quantity of antifungal bacteria in your batch of compost tea.

I am very happy that you have no or very little leaf curl and that you provide your trees with the bacteria to fight off any occurrence that might try to spring up.

Redhawk

Bryant RedHawk wrote:

R, you are so lucky to live in BC, the low humidity is one of your helpers when it comes to leaf curl as you have noticed. ...
Redhawk

It's not low humidity so much.  When it's not raining, everything is dew-drenched each morning except for a few weeks in August.  It's the family tradition to grow peaches and apricots under the overhang of the house where the dew doesn't reach.  A lot of people here tell us one cannot grow peaches where I live.  But I didn't know that until recently and we've always had a peach tree.  I bet if we tried to grow it out in the open, we would have a lot of trouble with the leaves curling.

There's a lot we do in our family because that's what was always done.  My father learnt from his grandfather who was a farm Boy (would be considered farm manager in these days) and did things the way that they had always been done.  Chemical and tractors were a recent invention and a waste of money because he could get better yields with less input using the traditional ways.  

Thank you for the compost tea recipe.  It is so much simpler than the one I have to spend a lot of time to gather the BSM, Fish Iso, kelp meal, rock phosphate.  
I have access to a lot of compost that is over a year old that I store in a large frame made of a cattle panel and landscaping cloth.
Your recipe will make things a lot easier.

hau R. I must have been thinking of Alberta, my wife was born in Vancouver but lived mostly in Alberta (Slave Lake, then Lethbridge).

I've been trying to get her to move back (the kids are in BC) but she keeps saying it costs too much to move there, so we will stay stateside.

It is great that you follow the pre tractor methods, they work far better for the land.

Redhawk

hau Dennis, glad to be of help. I've noticed that a lot of "experts" want to complicate what is really simple to achieve.

Most of the "fancy" components are to get certain minerals into the mix, sea-90 has the ability to provide all and more of what those "fancy" components would have in them.

Redhawk

Bryant - I mistakenly said sulphur spray, I meant copper spray. The UC Davis site recommended it or the Bordeaux mixture, and the copper spray was easy to just pick up, but as I say not helpful. Peach leaf curl is pretty ubiquitous in the Bay Area, Oregon seems a little better in this regard.

Bryant RedHawk wrote:

Stacy Witscher wrote: I tried liberally using a sulfur spray on the recommended schedule and it didn't seem to do anything at all.

hau Stacy, Most likely the sulfur spray was not the right type of sulfur spray and thus was not effective as you mention it not doing anything at all.

Bordeaux mixture works very well for eradicating the fungus Taphrina deformans, your best alternative is a good, aerated compost tea sprayed all over the tree and the surrounding soil. (this is working for fire blight on pears and apples too at my farm)

The other alternative is like others have mentioned, buying trees that have natural resistance to Taphrina deformans.

Redhawk

I think this quote was actually from me :D It's quite likely that I used the wrong kind of sulphur spray. My local garden store is unfortunately quite small so this is all they had for peach tree fungicides. I'm not really big into spraying and I have some other trees in the family that are less fussy so I think I'm going to go the route of getting more resistant trees. Whether I grow peaches vs plums vs apricots vs cherries etc doesn't make a huge difference to me.

Meg, I found this PDF document a while back and like how he presents the information about fruit trees that are easy to grow without chemicals and ones that take chemicals or some means to combat disease and insects.  
I have learned here at Permies that Compost Tea can take the place of some of the chemicals and have used to solve fire blight.  
But the list of trees listed in this document, are naturally resistant to the disease and insects we have here. I have been planting these trees before I found this document but it is nice to see some confirmation.
http://conev.org/fruitbook9.pdf

Thanks to all for all the suggestions above! Wish I had compost for some tea but just put all mine on the garden this spring!

I got looking over my peach tree last night and concluded that, since the infected leaves grow so much larger, thicker and much heavier than normal unaffected ones, they must sap a lot of moisture and nutrients from the tree. I doubt that once infected they are contributing much benefit to the tree, so I went over the tree and removed all the leaves that showed any signs of curl.  Hope I have done the right thing!  In the process I noticed quite a few little peaches I'd missed when thinning last week so have now removed over 1,000 in total!   (Sure wish the tree could bear to maintain that many!!!)

I've included below a couple of pics of the trunk of the tree and what the tree looks like with the curled leaves removed.  The trunk doesn't look all that healthy to me...any suggestions?

Here is the continuing saga of the peach tree pictured above..... After I stripped off all the curled leaves, the tree looked pretty bare and I wondered if it would have enough foliage to support the fruit it was carrying. But stripping all the affected leaves was probably the best thing I could have done. (I have not seen any more leaf curl on it this season!) Other leaves gave grown and it is just about to bear a bumper crop of great looking peaches, likely in early September. They are getting bigger and more colourful by the day but are still very hard. Here's a couple of pics of the same tree now.

This Elberta peach tree is a late bearer but the wait has been well worth it. It produces very large, sweet free stone peaches. Since we started picking (just after the beginning of September) it has yielded over 86 pounds of peaches and I'm sure the total will eventually be well over 100 pounds! Here's a couple of pics of part of this morning's pick...

Picked the last of the peaches from this tree for this year and we just cleared 100 pounds of fruit from this tree this season! My wife has been the busiest with processing it all. We have eaten loads, she's baked a few pies, made freezer jam but has blanched, peeled, sliced and frozen the most of them for use during the winter. Here's a picture of some of her labors: freezer jam, slices ready for freezing, frozen fruit in bags and some fresh fruit. We've had an awesome crop this year, Thank you Lord!