July Gardening Calendar - Colorado State University Extension Tri River Area Mesa Delta Montrose Ouray Counties

Sunday	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday
Week 1
Check the Dial-a-Garden Message weekly for updated information. Call (970) 244-1706 or see the Dial-a-Garden Main Page for this message.	.Fine stemmed plants such as perennial candytuft, snow-in-summer (Cerastium tomentosum), and rock cress (Arabis caucasica) can be sheared back one-half their former height to promote a second blooming.	The adult stage of the White Grub (aka June bug or May beetle) emerges and lays eggs in lawns at night. Preventative treatments for the white grub will be needed soon.	Elm Leaf Beetle: First generation larvae become full-grown and move down trunk to pupate. Small red bugs killing patches of grass in lawns may be a Chinch Bug. Bring in a sample for a positive identification.	Black Vine Weevil adults damage leaves of euonymous, lilacs and other plants. Small notches in the edges of leaves is this insect's trademark injury.	Maintain the grass (Kentucky Bluegrass, Tall Fescue and Perennial ryegrass) at a height of 2.5 to 3 inches. Cutting shorter will increase drought stress problems.	The chances for Herbicide Injury is more possible as days become hotter. The Amine form of 2,4-D is less likely to produce damaging vapors than the Low-vol or ester formulations.
Week 2
Top die-back of birch and Norway maples may be apparent this month. This is usually due to lack of proper watering during dry and open winters.	Dollar Spot occurs during high temperatures and on drought-stressed turf. Avoid overwatering as this may increase this fungus problem.	Inspect trees during July for the development of webs and feeding injury of Fall Webworm Sod Webworms cause damage on turf by clipping off the blades of grass.	The base of peach, apricot, cherry and plum should be drenched with insecticide or nematodes to control Peach Tree Borer. More in-depth information is available. Pine Needle Scale: Watch for second generation crawler activity.	Corn Ear Worm: Adults lay eggs on green silk. A drop of mineral oil in the ear tip helps control this pest.	Cooley Spruce Gall: dried galls are very conspicuous.	Pear Slug can be a serious problem on pear, cherry, and cotoneaster by eating the leaves. Only the veins of the leaves remain.
Week 3
Codling moth treatments should continue to control the second generation of this apple and pear pest.	Necrotic Ring Spot circles on lawns (aka Frog-eye) are usually more obvious in July.	During the hot part of July, more frequent applications of water may be necessary. If the lawn had been irrigated properly prior to this time, the root system of the turf should be quite extensive and the turf should be relatively resistant to drought.	Native trees and shrubs may need a thorough watering this month to help prevent root loss. This is important during dry, hot summers.	Maintain vigilance against the Geranium Budworm that feeds on the buds, flowers and leaves of geranium, petunia and other flowers.	Aphids and European Elm Scale on elm excrete large amounts of honeydew that drops on everything under the affected tree. Sooty mold fungi will colonize this honeydew turning leaves and branches black.	Peak damage by the tomato Horn Worm begins. Hand-pick these caterpillars off plants.
Week 4
Aerate those areas of the lawn that are suffering from drought due to compacted soil. A step-on, plug-type aerator is usually sufficient for small areas. Aerating will assist in the penetration of water.	Spider Mite injury on spruce and junipers can be lessened by a weekly syringing of these plants with water.	Mountain Pine Beetle: Adult flights and new atttacks of pine trees occur around this time.	Virus problems of Tomato and vine crops will begin to appear in mid to late July. Sprays to control the insect vectors of virus should have begun earlier in the season. Pull and destroy all virus infected plants and apply insecticide sprays to help prevent the spread of the virus to neighboring plants.	Yellow leaves on willows can be caused by aphids or spider mites. Fallen leaves should be checked for these pests and the proper treatments made to prevent further defoliation.	Sweet corn leaves roll when needing water. Pumpkin and squash plants may wilt in late afternoon. If these plants don't recover in the evening hours a thorough watering may be in order.	Elm Leaf Beetle: egg laying and hatch of the second generation of this pest occurs in late July.
Week 5
Cone flower, "Autumn Joy" sedum and astilbes produce attractive seedpods you may wish to leave for winter enjoyment.	Honeylocust Spider Mite populations increase rapidly during hot dry months of summer. Leaf bronzing of honeylocust will occur with this pest.	Continue to cut the dead flower heads from your perennial flowers except those you would like to self-seed such as columbine and foxglove.