Peach Leaf Curl-Spray or Not Situation

I’m beginning my first spraying for PLC for some in ground Nectarines.My question is about some in pots.They have been outside since late Summer and have been rained on this Fall.They will be brought into a greenhouse before bud break next year.Should they be treated also?
I’ve read that in order for the fungus to work,it has to be wet for 12.5 hours,with the temperature below 61F.Is this only in the Spring or will Fall conditions like this infect the plants and bring about the disease if I don’t spray and even if they are moved under cover,during the Spring? Thanks,Brady

I think if dry in spring you won’t need to spray. The infection occurs during bud break in spring. I don’t think infection can occur now. I could be wrong because one might ask why spray in fall. I think that’s to lower innoculum level and get some spray material down in all the cracks and cervices of bud scales.

That sounds right fruitnut.Every place I’ve read so far has the conditions for fungal infection happening at bud break. Brady

Yes, the idea for spraying in the fall is to lower the innoculum level (i.e. kill the fungus on the wood). I also think w/ copper and chlorothalonil, they may have some residual effect even till spring. I’ve noticed both copper and chlorothalonil are very slow to wash off. I’ve seen copper stay on the trees all through winter. I also once got some overspray of chlorothalonil on a window and it took forever to wash off by natural rainfall.

Olpea,what brand of Copper is that?I’m trying Monterey’s Liqui-cop for the first time after two unsuccessful years of using Bonide’s Fung-onil.The Copper product is a dark blue,but didn’t really notice it on the trees after spraying.I’ll have to take another look.I also added a sticker. Brady

Liqui-cop is about the best liquid copper around, but it is weak compared to other dry agents like Kocide. I myself wait till spring to spray it. I use Lime-sulfur in oil this time of year. I like it for insect eggs and powdery mildew spores and other fungal problems mostly on other plants, but hit my trees too except apricots or pluots. I use a generic Kocide with Nu film 17 in the spring. I have never had peach leaf curl, but my trees have only seen 3 springs, so young trees. I have seen it on other nearby unsprayed peach trees. So for sure it’s around. So far so good.


I haven’t used copper for a few years, but as I recall, it was the Kocide Drew mentioned. I too use a sticker w/ peach leaf curl fungicides.

Yes, you once worked out amount on garden web for a user. And I figured out amount for the stronger generic kocide, which is not labeled for use on fruit trees, but is the same chemical in kocide, just at a higher percentage of active ingredient.
2 tbsp per gallon for kocide Fall and spring while dormant. (olpea suggestion)
For generic CuPRO use 1.5 tbsp per gallon. (drew suggestion)

Use amounts at own risk!

And I highly suggest using Nu Film 17 sticker or another high end professional sticker. Nu Film is made from pinene an extract from pine trees. This also is the chemical in Wilt Stop, although prepared in different ways. Baseball players use pine tar to grip the bat, we use pinene to grip the tree. The stuff will stay there though numerous rain storms. Do not use Bonide sticker, or other consumer stickers. They hardly work at all compared to Nu film. Other professional stickers are also very good maybe even better.

On Chlorothalonil, using professional versions will probably obtain much better results than Fungonil. I bet the active ingredient is a lot stronger. If you have the bucks you can buy it. Same with Captan, one should buy the professional versions. I could use math help with gallon doses of 50WP and 80WDG Captan.
I’m still using Bonide Captan, which works, but I can see wanting the stronger stuff down the road when i run out. I figure I’ll try 50WP first. I really need this for my strawberries as gray mold is a problem here, and this is the only thing that works.

Would it serve any purpose to spray the orchard floor with copper and lime sulfur now in Z5b.

Most of the fallen leaves have been blown against the back fence for easy removal (yeah!). But the floor is pretty heavily mulched with wood chips.


I may try upping the dosage of Fung-onil on some seedling trees in the future,to see the effect. Brady

Hard to say? I don’t know? I spray the trunk and drip area though.

If I have time I’ll see if any difference between products. I would use both your copper and fung-onil at this point. Maybe at different times, although both during dormancy. I like the liquid copper for melons, cucumbers, as a preventative. It can be used on just about anything.
Again the product I use is CuPRO

In Nov last year I dug up an in-ground genetic dwarf peach tree, barerooted it, and planted in a large container. I kept it outside but sheltered from rain.

In previous years all of my genetic dwarf peaches were devastated, often with many dead branches and few if any usable peaches. I dug up this one because it was small, although I did need to cut the tap root because it was so deep. I planted it in a large container in potting soil.

That tree did great. It had almost no leaf curl. It was covered with peaches, I had to thin aggressively. It was the best crop I ever had.

The in-ground peaches were covered with leaf curl as in previous years.

I also have 2 nice seedling genetic dwarf peach trees. I kept them out of the rain last winter and they had no leaf curl at all this year. They were in an unused doghouse outdoors.

I suppose your container trees won’t be harmed by spray, but based on my experience it doesn’t seem necessary, either, for trees that will not be in the rain.

Yum those look nice! I might get some dwarf trees for ornamental reasons and fruit! What cultivar is that? The fruit looks good! Mine are all in ground, although I have never seen PLC with treatment. At my cottage 35 miles away a friend has a couple trees, uses no treatment and has PLC and all the fruit had worms. Probably PC I guess? Yeah PLC can get so bad here too where branches begin dying.


I get good control of PLC from one spray. Although I am aware some areas require multiple sprays for control. I don’t spray the orchard floor (other than what drips from my trees) in my backyard orchard. However, I use an airblast sprayer with my larger orchard and it does pretty much blanket the area with pesticide. For wand spraying, I’ve not seen any recommendations to specifically spray the ground.

Drew those were El Dorado. They were so delicious. Not big, but I dont care, just delicious.

in container, they did need watering every day. during the hottest weather, twice daily. I kept them mulched and used s light colored container.

I have Honeybabe in ground. If it wasnt so big, I would dig it up and do the same thing.

Well darn!!! For the first time ever, I have peach leaf curl in my orchard- pretty bad on some trees. I’m sure it is no coincidence that this is also the first year I failed to spray copper on many of my trees. Hard lesson to learn.

Most of my peaches are at shuck split (those that have any peaches) and leaves are between 1/2 size and full size.

Is there anything I can do now to minimize the damage? Picking off the bad leaves is not much of an option- too many trees that are too big. Does peach leaf curl do a lot of damage to the fruit or just the leaves? Thanks

If the leaves are out, then its too late to spray anything. Might want to really hit it good with N for the new leaves. You can rake up the old crusty ones when they fall. I haven’t been hit with PLC for many years. A late spraying of copper seems to work for me. I sprayed this afternoon and my peaches are just starting to show some green.

This is ghetto…but i got the whole container for a couple bucks on clearance years ago. I have used it since then with no ill effects that i’ve noticed. I just take a table spoon of the crystals and put it in a small spray bottle and let it dissolve. Seems to work. Cheap.

That is pretty much what I figured. I wonder if my copper has been working really well in the 4 years since I started my orchard (I used it every year but this one) or if this is the first year PLC has arrived in my orchard? Maybe a combination of both since I brought in several new trees this year and didn’t spray copper for first time.

I admire your ingenuity with using that product, but I’d have a hard time spraying root killer all over my trees!!! haha. (I understand it is in small concentration, etc),

This may be the first year my outdoor Nectarines and a few new Peach grafts don’t get PLC.
I was tired of dealing with the ugly,misshapen leaves and so,with the last spray of Copper this season,I probably quadrupled the amount,along with the sticker.Right now,with the new leaves growing,it doesn’t look like any is there. Brady

I got two sprays in this spring. I just sprayed a few days ago. No leaves yet here. I’m done though, it has always worked. I use heavy duty stuff, A generic Kocide. Which is not a sulfate, copper the active ingredient.