To Sacramento gardeners, summer rain may seem like an unexpected treat, a gift of extra moisture during an already wet year.
But for peach growers, recent June storms caused more grief than joy. Poorly timed summer rain followed by warm weather can devastate ripe peaches, quickly turning beautiful fruit into brown mush.
“Rain will rot peaches in 24 hours,” explained Vicky Tomich Allen of Tom Tomich Orchards in Orangevale. “The worst sound to me is summer raindrops on the roof.”
Last week, Allen and her family scrambled to bring in ripe Zee Diamond peaches before the rain could ruin their precious fruit. For five generations, the Tomiches have been growing peaches, plums, nectarines and other fruit on the same Orangevale farm since 1897.
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“Every summer, there would be at least one night where we woke up to rain and ran out into the orchard,” Allen said. “We’d be out there picking fruit with flashlights, trying to save what we could. We could lose hundreds of boxes with one rainstorm.”
The problem is not confined to commercial growers. Backyard peaches and nectarines are subject to the same issue: brown rot. This fungal disease can attack plums, cherries and almonds, too. Some varieties are more susceptible than others.
“Water can accumulate in that little notch in a peach,” Allen said. “That allows the fungus to get a toehold and enter the fruit. Once the fungus enters, it’s all over.”
Ripe fruit can be saved if quickly picked and dried. Peaches within a day or two of full ripeness tend to be the most susceptible.
Brown rot fungus overwinters on the tree, usually in fruit “mummies” – little shriveled brown fruit that never develops yet clings to the branch. Always remove mummies; otherwise, they’ll come back to haunt your fruit tree with more brown rot fungus.
For home gardeners, prevention is key. Clean up fallen fruit – and watch out for mummies.
Brown rot is a lot worse in areas that stay wet and humid all summer. It attacks blossoms as well as ripening fruit.
Sprayed in late winter before flowers buds set and then repeatedly during the growing season, fungicides can help control brown rot, but that approach is usually not needed here. Dry, hot summer weather – normal for Sacramento – keeps brown rot mostly in check.
As long as it doesn’t rain.
“I should be enjoying the rain; it’s free water,” Allen said during last week’s storms. “But Mother Nature runs the show all the time. We go with her plan.”