Q.replacing a peach with a new tree
hi, i bought a young peach tree about three years ago from the local garden center sadly it came with leaf curl which took me two summers to work out. since then i have thrown everything at it that anyone and everyone has recommended to no avail. i have now found a replacement which by all accounts is advertised as highly resistant which i am currently waiting delivery. the question is, is can can i replant in the same position as this is where i would really like it to be or am i tempting fate. is there anything i can do to prepare the ground or say pot plant it for a couple of years first. i also have access to an area outside the garden which i could plant the old one in and try neem oil something i have never heard of until coming across your site. i hate throwing away plants of any form and am more like to bring home half dead ones.
Hi Joe; Peach leaf curl may not have been the responsibility of the nursery that sold you the peach tree. In some years when the conditions are right, the infections are more prevalent and more aggressive; if you have a peach tree the pathogen spores will find it.
Also, it is not a soil borne disease, although fallen leaf litter from your infected tree can serve as an inoculant source for subsequent seasonal infections. So just practice good garden sanitation and clean up fallen leaves and twigs, dispose of the litter. You can plant in the same location, but improve the soil as best you can before planting.
Provide good soil fertility and water management and your tree will be more resistant, but in my opinion, the only way to fully control the disease is with preventive fungicide spraying during winter dormancy.
My plant pathology professor many years ago recommended 'lime sulfur' as the only reliable effective fungicide for peach leaf curl, so I have used it successfully ever since. The attached article says it is not as effective, I don't know why, but I have used it for my customer's trees for years. I tank mix it with horticultural oil and it adheres to the plant surfaces very well and doesn't wash off readily with rains. It is organic program compatible because it biodegrades and is not persistent in the environment, but it stinks and is highly hazardous for the applicator, with skin irritation and eye damage possible if you don't fully cover up to protect yourself while spraying. It is legally restricted against residential use in some areas.
In the mild California climate, I do the first dormant spraying during the first week of December, then January and February. You can't spray foliage or it will burn, only bare stems and unopened buds. So after bud break I switch to a biological fungicide. If you don't use organic methods and materials, there are hard chemistry fungicides available now, like propiconazole, which is reported to be effective. I haven't used it for this issue.
70% Neem oil is an excellent organic program fungicide-miticide-insecticide, but it has to be sprayed every two weeks as a preventive (not a cure) to be effective. Which is not always practical or affordable. It would not be my choice for peach leaf curl. It's best for use during the growing season. Winter spraying every two weeks would be no fun and may not be effective at all. Hope that helps, Don