Copper sprays can be effective if applied during dormancy
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Distorted and blistered leaves are signs of peach leaf curl.
Now is the time to spray peach and nectarine trees to control it. (Photo courtesy UC Statewide Integrated Pest Management) |
It may be Thanksgiving, but it’s time to talk peaches. In particular, this conversation is about peach leaf curl.
This common fungal disease only attacks peach and nectarine trees. It distorts and puckers foliage and new shoots. It can completely defoliate a tree, leaving any developing fruit to sunburn or shrivel. Over time, it greatly cuts down on a tree’s productivity.
And it comes back, year after year after year. Once it’s established, peach leaf curl will be an issue every spring.
The time to combat this fungus is not when you see its damage in April or May; it’s now, in the days before and after Thanksgiving.
To control leaf curl, peach and nectarine trees benefit from dormant spraying with a copper fungicide or copper soap. Horticultural oil helps make that copper spray stick to the twigs and branches.
According to the UC Integrated Pest Management Program, the copper spray smothers the fungal spores that overwinter on the tree.
“The fungal spores that cause the disease spend the winter on twigs and buds and germinate in the spring,” say the IPM experts. “For effective control, treat trees just after leaves have fallen, usually late November or December.
"A second application in late winter before buds swell can be considered, especially in areas with high rainfall or during wet winters. Don’t apply fungicides during the growing season because they won’t be effective.”
A dry, calm and fogless almost-winter day; that’s the perfect time to spray. And that’s also the forecast for the greater Sacramento area this Thanksgiving weekend and early next week. Copper sprays need 24 hours of dry, calm weather before and after application. This is a good window of spraying opportunity.
If needed, prune before spraying. Pick up any dropped foliage and discard (don’t compost). Those fallen leaves may carry leaf curl, too.
For more on treating peach leaf curl: http://ipm.ucanr.edu/QT/peachleafcurlcard.html
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Food in My Back Yard Series
SUMMER
July 15: Does this plant need water?
July 8: Tear out that sad plant or baby it? Midsummer decisions
July 1: How to grow summer salad greens
June 24: Weird stuff that's perfectly normal
SPRING
June 17: Help pollinators help your garden
June 10: Battling early-season tomato pests
June 3: Make your own compost
May 27: Where are the bees when you need them?
May 20: How to help tomatoes thrive on hot days
May 13: Your plants can tell you more than any calendar can
May 6: Maintain soil moisture with mulch for garden success
April 29: What's (already) wrong with my tomato plants?
April 22: Should you stock up on fertilizer? (Yes!)
April 15: Grow culinary herbs in containers
April 8: When to plant summer vegetables
April 1: Don't be fooled by these garden myths
March 25: Fertilizer tips: How to 'feed' your vegetables for healthy growth
WINTER
March 18: Time to give vegetable seedlings some more space
March 11: Ways to win the fight against weeds
March 4: Potatoes from the garden
Feb. 25: Plant a fruit tree now -- for later
Feb. 18: How to squeeze more food into less space
Feb. 11: When to plant? Consider staggering your transplants
Feb. 4: Starting in seed starting
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Garden checklist for week of July 13
Put off big chores and planting until later in the week when the weather is cooler. In the meantime, remember to stay hydrated – advice for both you and your garden.
* Keep your vegetable garden watered, mulched and weeded. Water before 8 a.m. to reduce the chance of fungal infection and to conserve moisture.
* Water, then fertilize vegetables and blooming annuals, perennials and shrubs to give them a boost. Feeding flowering plants every other week will extend their bloom.
* Give vegetable plants bone meal or other fertilizers high in phosphate to stimulate more blooms and fruiting.
* Add some summer color. Plant petunias, snapdragons, zinnias and marigolds.
* From seed, plant corn, pumpkins, radishes, winter squash and sunflowers. Plant Halloween pumpkins now.
* Pinch back chrysanthemums for bushy plants and more flowers in September.
* Remove spent flowers from roses, daylilies and other bloomers as they finish flowering.
* Pinch off blooms from basil so the plant will grow more leaves.
* Cut back lavender after flowering to promote a second bloom.
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