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Landscape & Garden Alerts

Showing 25 most recent Landscape and Garden alerts

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Freeze Alert

Landscape and Garden    Treasure Valley

Frost

Posted on: September 28, 2019 by Maria Held

Sunday to Tuesday morning temperatures are forecast to dip near or below freezing. Harvest or cover you sensitive plants to protect them from the low temperatures.

Treasure Valley Tomato Taste Off & Information Tables

Landscape and Garden    All Locations

Posted on: September 16, 2019 by Maria Held

Third Annual FREE Tomato Taste Off Saturday, September 21, 2019 at the Indian Creek Festival in Caldwell.
Entries can be dropped off at the Canyon County Extension Office,
501 Main St, Caldwell on Friday September 20 from 1:00 PM-4:30 PM
or bring them to our festival booth from 9:00 AM-10:30 AM on Saturday. Enter 4 cups of cherry tomatoes or 3 (larger) to 5 (smaller) slicers or paste tomatoes to compete for prizes. Tasting and voting will be from 11:00 AM-1:00 PM

Fruit Field Day at Parma Research & Extension

Landscape and Garden    All Locations

Posted on: August 29, 2019 by Maria Held

The University of Idaho Pomology and Viticulture Fruit Field Day is taking place on Friday, September 6th from 8:30 am to 1 pm at the University of Idaho Pomology Research Orchards and Vineyards
31727 Parma Rd, Parma, ID 83660. This is a free event for anyone interested in fruit production.
Please RSVP to maurineb@uidaho.edu or call 208-791-6228 with the number in your party.
See the attached flyer for directions.

Tomato Fruit Issues

Landscape and Garden    All Locations

Posted on: August 19, 2019 by Maria Held

Are you experiencing issues with you tomato fruit like blossom end rot, catfacing, splitting, zippering and such? Below are some links to help you determine what is going on with your tomatoes. Remember that variety selection and consistent watering are important in preventing some of these problems.

Blossom End Rot on Summer Squash and Tomato

Landscape and Garden    Treasure Valley

Blossom End Rot on Squash and Tomato

Posted on: July 31, 2019 by Maria Held

Blossom end rot is showing up on summer squash. Tomatoes, peppers, eggplant and even watermelon may be affected. It occurs in the first fruits formed on the plants and is caused by a lack of calcium in the fruit. Most garden soils a sufficient supply of calcium; refer to your soil test results. However, uneven watering may cause symptoms in fast growing plants.

Blossom Drop on Tomatoes and Peppers

Landscape and Garden    Treasure Valley

Blossom Drop

Posted on: July 29, 2019 by Maria Held

Gardeners are experiencing blossom drop on their tomatoes and other vegetables. This is due to high daytime > 90 F and low nighttime <55 F temperatures we have been experiencing. Pollen becomes sterile during hot weather. Fertilizer high in nitrogen and lots of water lead to growth of leaves instead of fruit set.

Beet Leafminer in Gardens

Landscape and Garden    Treasure Valley

Posted on: July 20, 2019 by Maria Held

Are you noticing papery areas or tunneling on you beets, Swiss Chard or spinach? The leafminer fly lays white eggs on the underside of leaves. The resulting larvae burrow inside the leaves to feed. See the links below for management options.

False Chinch Bug Migration

Landscape and Garden    Treasure Valley

Nysius raphanus

Posted on: July 19, 2019 by Maria Held

The Caldwell Extension office has received multiple calls of masses of false chinch bugs. They may aggregate in large numbers on buildings or driveways especially if hosts are harvested or managed with herbicide. See the attached photo of a false chinch bug aggregation on a driveway.
Insecticides will have little, if any, effect for limiting this situation and are not recommended. False chinch bug migrations resulting in nuisance problems in buildings usually are of short duration and rarely last more than a week.

Earwigs Everywhere

Landscape and Garden    Treasure Valley

Forficula auricularia

Posted on: July 12, 2019 by Maria Held

Garden plants commonly injured by earwigs include annual flowers (especially marigolds, dahlias and zinnias), herbs (especially basil), roses, raspberries, strawberries, apricots, peaches, sweet corn tassels and silks. Because earwigs are beneficial due to their predaceous and decomposer feeding habits, they should only be controlled when causing harm. Earwigs are nocturnal. If chewing injury to plants is apparent but no culprit can be found during the day, check the plants at night with a flashlight. If shiny, slime trails are present, snails or slugs are the culprit rather than earwigs. Trapping is an effective way to control the population.

Squash Bugs are here!

Landscape and Garden    Treasure Valley - Idaho

Anasa tristis

Posted on: June 27, 2019 by Maria Held

Squash bugs and eggs have been found yesterday at the IPM scouting walk at Idaho Veterans Garden in Caldwell. The insects affect cucurbits and vine crops sucking sap from the plants. Check the underside of leaves for egg masses and destroy them. The adults are hard to control. Always follow label instructions.

Peach Twig Borer 2019

Landscape and Garden    Treasure Valley

Peach Twig Borer Anarsia lineatella

Posted on: June 17, 2019 by Maria Held

Peach twig borers have been found in a trap in the Payette area. Peach twig borer is the “worm in the peach”.
Peach twig borer larvae prefer to bore into succulent twigs. Later in the season, when twigs become hardened off and unpalatable, larvae feed inside the fruit.

Squoia Pitch Moth

Landscape and Garden    Treasure Valley

Synanthedon sequoiae

Posted on: June 6, 2019 by Maria Held

Spitch moth has been found in traps.
The sequoia pitch moth (SMP) is the primary insect that causes large pitch (resin) masses on Austrian, Scotch and other ornamental pines.
SPM is not typically considered a serious pest of pines, but may cause limb dieback, unsightly resin masses, tree stress or tree death in severe cases.
There are no recommended insecticide control options for SPM.
SPM should be managed using cultural controls such as removing resin masses and larvae, proper timing of pruning, eliminating mechanical damage and proper irrigation. Avoid pruning/injuring trees April through August.

Western Cherry Fruit Fly 2019 Update

Cherry    Treasure Valley

Western Cherry Fruit Fly WCFF

Posted on: June 5, 2019 by Paul Castrovillo

On May 29 the first 2019 Western Cherry Fruit Fly captured in an Idaho State Department of Agriculture WCFF trap was reported from Canyon County. Historically we expect to find WCFF in Gem County about a week after the first one is found in Canyon County.
Online phenology and degree-day models for WCFF predicted first flight on May 26 in Emmett, May 28 in Ontario, Parma and Boise and May 29 in Caldwell and Nampa.
If treatment for WCFF is not already underway it should begin now.

Western Cherry Fruit Fly 2019

Landscape and Garden    Treasure Valley

Rhagoletis indifferens

Posted on: June 3, 2019 by Maria Held

Western Cherry Fruit Flies have been detected in Boise. Once your cherries are starting to blush (turning from green to yellow to light pink) it is time to protect them. At that stage the cherries are soft enough for being penetrated. Spraying with Surround (kaolin clay) creates a physical barrier that prevents females from laying eggs into the developing fruit.
See the links below for more options.

Powdery Mildew on Ornamentals

Landscape and Garden    Treasure Valley

Sphaerotheca pannosa var. rosae

Posted on: June 1, 2019 by Maria Held

Powdery mildew continues to be a problem with all the rain we have had. It has been reported on roses and peonies. Powdery mildews are characterized by spots or patches of white to grayish, talcum-powder-like growth.
When available choose resistant or tolerant varieties. The disease is common in crowded plantings where air circulation is poor and in damp, shaded areas. Avoid overhead irrigation once symptoms occur. Do not compost infected plant debris. Temperatures often are not hot enough to kill the fungus.

Apple Codling Moth First Generation

Landscape and Garden    Treasure Valley - Idaho

Posted on: May 22, 2019 by Maria Held

The first Apple Codling Moths have been trapped at the beginning of May (Biofix on May 2nd). However, flight activity has been slow because of rain and low temperatures. We are currently at 197 Degree Days (DD) and treatment is indicated at 220 to 250 DD expected no sooner than this weekend depending on weather conditions.

Be prepared, because this is a pest that you need to prevent all season long for clean fruit. Whether you are growing organic or conventional, the only non-spray option for clean fruit is to bag them.

Aphid Damage

Landscape and Garden    Treasure Valley

Aphid

Posted on: May 16, 2019 by Maria Held

Aphids have been found on trees (ash, plum) and ornamental plants (roses, daisies). Look for sticky sap and curled distorted leaves. A stream of water is often all that is needed to dislodge the insects from the plant.

Cabbage Looper

Landscape and Garden    Treasure Valley

Cabbage Looper Trichoplusia ni

Posted on: May 13, 2019 by Maria Held

Cabbage looper adults (moth) have been caught in pheromone traps.
Cabbage looper larvae feed on all cole crops (cabbage, broccoli, cauliflower, Brussel sprouts, kohlrabi, kale) and leave behind frass. Cover you cole crops with row cover or insect barrier to keep out the loopers.

Lilac/Ash borer

Landscape and Garden    Treasure Valley - Idaho

Lilac/Aash borer Podosesia syringae

Posted on: May 10, 2019 by Maria Held

Lilac/Ash borers have been caught in traps. Trunk treatment of ash trees is indicated in 10-14 days when the eggs hatch.

Peach Leaf Curl Detected

Landscape and Garden    Treasure Valley

Peach Leaf Curl

Posted on: May 7, 2019 by Maria Held

If you are experiencing symptoms of peach leaf curl make sure to spray this fall when most of the leaves are off the tree. Since it is a fungus there are no management options after infection has occurred.

Weekend Weather Favored Fire Blight Development

Landscape and Garden    All Locations

Fire Blight

Posted on: April 23, 2019 by Maria Held

Weather conditions over the past weekend (rain and higher temperatures) were favorable for fire blight as pear and apple trees are blooming. This bacterial disease affects the rose plant family (Rosaceae ).
Temperatures over 70 F and moisture (rain, dew) foster fire blight development.
Monitor trees closely starting two weeks after full bloom (which is when infections start to become visible). Prune out new infections immediately (on a dry day).
Refer to the references below for additional information:

Spring Garden Festival and Plant Sale

Landscape and Garden    Treasure Valley

Posted on: April 22, 2019 by Maria Held

The Canyon County Master Gardeners Annual Spring Garden Festival and Plant Sale takes place on Saturday, April 27th from 9 am to 3 pm at the Canyon County Extension Office in Caldwell on 501 Main St.
A free Gardening 101 class is scheduled for 10 am and 1 pm. Informational tables on tomato trellising, transplanting, composting and more will be offered. Master Gardeners will be on hand to answer your questions.
A variety of vegetables (lots of tomato and pepper plants), herbs, annual and perennial flowers including succulents and pollinator plants, houseplants and a few shrubs and conifers are available for sale. Prices start at $1 up to $10 depending on type and size of plant.
All proceeds go to Master Gardener Scholarships.

Dormant oil spray

Landscape and Garden    Treasure Valley

Posted on: March 15, 2019 by Maria Held

Despite the fact that we call it “dormant oil”, the timing of a horticultural oil spray is not when trees are still dormant. A better term would be a “delayed-dormant” application, because the oil should be applied after bud swell. This coincides with the increasing activity of the overwintering insect, such as aphid eggs, scale nymphs, and peach twig borer larvae.

Canyon County Master Gardener Program 2019

Announcements    All Locations

Posted on: November 27, 2018 by Dian Roberson

The Canyon County Master Gardener Program is now accepting applications for the 2019 Master Gardener Class! For more information contact the Canyon County Extension Office at 501 Main St., Caldwell, ID 83605; 208-459-6003; or ccmg@uidaho.edu

Peach Leaf Curl Spray

Landscape and Garden    All Locations

Taphrina deformans

Posted on: October 31, 2018 by Maria Held

If you experienced peach leaf curl on your trees this spring it is time for treatment when most of the leaves are off the tree. Resistant varieties are a good option for home gardeners.

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