is immunity from peach leaf curl possible?

Hello permies!

Peaches are my favourite fruit, and a healthy peach tree is one of the most beautiful sights in a garden. However, it is frustrating and saddening to see how, in my climate, these trees get mutilated (and eventually killed) by peach leaf curl.

Over the years, people have kept telling me that if I want to eat peaches from my trees, I have to spray each year with copper fungicides. I have refused to do that. (I do spray them with potassium bicarbonate and some home-made concoctions obtained from horsetail and nettle - but to be honest, I'm not sure these treatments are helping much.)

Some of the first trees I planted got sick in their first spring, and died within a couple of years.  

Other trees - especially of the Red Haven and Crest Haven variety - seemed more resilient, they got hit by the disease, lost some leaves, but quickly grew new ones and managed to produce fruit AND some (modest) new growth.

Then I also planted peach trees that were sold to me as "wild peach" - perhaps just trees grown from seed? - which turned out to be fast growers, but were still susceptible to peach leaf curl, although seemed to completely recover from the disease. These trees produced good quality (though smallish) fruit, BUT ONLY IF they were not hit too hard by the disease.

This year I'm trying some Italian varieties that are purported to be leaf curl resistant (or, according to one source, immune !!). Fingers crossed...

With this in mind, my questions to the Permies fruit grower community are the following:

I've been wondering how such a disease-susceptible tree could be cultivated thousands of years ago in China, in a region whose climate is not so different from the one I'm in now (central Italy)?

Considering that this tree seems to be so intent on getting sick and dying, what did ancient Chinese growers know about it that we don't? Did they spray copper fungicides? Did they spray anything? Did they have resistant or immune varieties?

Are there REALLY immune varieties?

PS: I've seen ornamental peach varieties with red / purple leaves that never got sick - beautiful trees, with very vigorous growth - however, I suspect that their fruit is not very tasty. Does anyone have experience with these trees?

When we breed new varieties, we get what we select for. For the past 60 or so years, plant breeders selected heavily for varieties that require coddling.

To get around that in permaculture, stop planting varieties that got selected to rely on purchased inputs. Grow plants from seeds. Cull those that fail to produce fruit because of peach leaf curl. Repeat for as many generations as needed to find families resistant to the common peach diseases.

The family tradition is to grow the peach tree under the overhang, on the west side of the house and trim off any branches that get beyond the overhang.  

I've never seen it grown successfully away from a wall.  But that could be a climate thing.  They come from the Middle East or parts of China where there is a lot of dry, hot summers without dew or rain to hit the leaves.  When peaches made it to Europe, it became standard to grow it against a wall - either a house or garden wall - with an overhang.  

Not sure if there are modern varieties that can grow out in the open in climates where there's a lot of dew or rain in the growing season.  

Here are some photos I took of my three peach trees yesterday, after a very wet spring.

Two photos of my paraguay flat peach, which is suffering quite badly...





My yellow peach, also suffering.





And finally a photo of my three year old seed-grown red moselle vineyard peach, which flowered for the first time this year and is already busy producing its first fruit.



There are a couple of curly leaves, but really nothing to write home about.

I sure hope the fruit is good, because I absolutely love everything else about this little baby tree. And yes, I said three year old from seed!

I agree with everything said in this thread: curl-free peaches are possible, you just have to select for them. If I were you, I would find the most curl-resistant tasty peach I could and grow out some seeds from it. Rinse and repeat every generation. Alternatively, you could try crossing a tasty peach with one of the ornamental peaches with disease resistance. Peaches fruit very quickly from seed (sometimes in as few as 2 years), so progress goes quickly.

Anecdotally, my seed-grown peaches seem consistently more resistant than my grafted varieties.



These are seedlings from a peach that was growing in a ditch on the side of a freeway. The mother tree was curl-free, and the peaches had bitter skin, which deterred bird, bug, and squirrel damage.

My only red-leafed nectarine gets terrible curl, but I'm sure it varies by variety.

My peach trees are all from grocery store peaches, just tossed the seeds in the garden and some grew back. 11 trees now, and expecting a bunch more seedlings this year. I have never tried to treat the disease.

They vary a lot in resistance to leaf curl. A few hardly seem to get it, and produce lots of good fruit. Others never produce a single fruit, and few trees I cut out and destroyed. The nectarines were the worst. Never got a single good one, and cut them down last year. But there are trees that resist the curl year after year and make good fruit.

Good luck!