1712 Claflin, 2021 Throckmorton Plant Science Center
Manhattan, KS 66506 (785) 532-6173
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ANNOUNCEMENTS
K-State Garden Hour
Wednesday, August 6, 2025 Noon to 1:00 PM CST
Register here.
Join Dr. Cheryl Boyer, Professor and Extension Specialist, as she highlights research projects addressing horticultural specialty crops such as ornamentals, fruits and vegetables, and turfgrass.
Register for this free Zoom Webinar at: https://ksu.zoom.us/webinar/register/WN_lXljvtedRu-pvfFA6Kzvxw#/registration
Welcome! You are invited to join a webinar: K-State Garden Hour Webinar Series. After registering, you will receive a confirmation email about joining the webinar.
ksu.zoom.us
Kansas Turf & Ornamentals Field Day
Thursday, August 7, 2025
Rocky Ford Turfgrass Research Center in Manhattan
This Field Day program is designed for all segments of the turf & ornamentals industry — lawn care, athletic fields, golf courses, sod farms, landscape, nursery, and grounds maintenance. Included on the program are research presentations, problem diagnosis, commercial exhibits, and equipment displays. There will be time to see current research, talk to the experts, and get the answers to your questions.
For more information and to register online, go to: www.kansasturfgrassfoundation.com
GARDEN TO-DO
Plan/Plant fall salad garden.
Divide iris if needed.
Do not fertilize the warm-season turfgrasses, buffalograss, zoysiagras and bermudagrass, past August 15. Doing so may increase the chances for winter damage.
Check mulch layers and add additional material if needed.
Transplant cabbage, broccoli and cauliflower to their final location.
Plant salad crops such as lettuce, radishes, spinach, turnips, mustard and other greens from mid-August to early September for a fall harvest.
Harvest vegetable crops on a regular basis for season long production
FRUIT
Fertilize Strawberries
Strawberries should be fertilized from now through mid-August to support fruit development next spring. Sunlight and warm temperatures from June through August promote runners and daughter plant development. As the daylight hours decrease and temperature begins lowering into September and October, fruit buds start to develop which is why this is the time to fertilize.
Nitrogen can be applied as part of a complete fertilizer (such as 12-12-12) at a rate of ¾ to 1 pound per 25 row feet. Alternatively, urea (46-0-0) can be applied at a rate of 1/4 to 1/3 pound per 25 row feet. Apply 1/2 inch of water after fertilizing to dissolve and move the nitrogen into the soil.
Harvesting Pears
Pears are typically ready for harvest from now through October. Pears left to ripen on the tree may develop a gritty texture. Harvesting at maturity but before peak ripeness along with a chilling period can bring out the sweet flavors.
When ready for harvest, pears change to a darker green color. Some varieties will have brown spots on the skin. These are the fruits’ “breathing pores” known as lenticels. On immature pears the lenticels are white or greenish-white. Mature fruit will develop a waxy coating and separates easily from the branch when twisted. There should also be a pear aroma at maturity.
To harvest, carefully lift the fruit at an angle and twist to remove. Avoid damaging the twig where it attaches as this could negatively impact fruit development next year. Refrigerate newly harvested pears at 31 to 50 degrees F for two days to several weeks depending on the variety. Remove pears from the cold storage and allow to sit at 60 to 65 degrees F for one to three weeks to finish ripening. Fruit may rot instead of ripening if conditions are too warm.
VEGETABLES
Still Time for Salad Garden
Radishes, spinach, turnips, mustard, lettuce and other leafy greens can be planted from mid-August to early September extending the harvest into fall. If planting in-ground, plant seeds slightly deeper than recommended for spring. This will give seeds access to slightly cooler soil that retains more moisture. Provide regular water until seeds germinate. Sprinkle a light layer of compost over the top of the seeds to prevent the soil from forming a crust.
An alternative way to grow a salad garden this fall is using a bag of potting media. Lay the bag flat and cut it open, on the long side, exposing the media as shown in the photo. Plant the seeds as recommended on the packet. Fertilizer may be necessary depending on the type of media used. Once planted, the salad garden bag should not be moved or the seeds will be displaced. Prior to planting, place the bag on a pallet or similar support, making it possible to move the planting as needed.
One benefit of growing fall greens in a potting media bag is the temperature of the media can be regulated by relocating the bag. This is particularly helpful during August and September when the heat can hinder germination and negatively affect flavor of certain cole crops. Due to the limited amount of soil, monitoring moisture is essential to crop success.
Harvesting Winter Squash
Spaghetti squash, butternut, acorn and hubbard are all examples of winter squash. Contrary to their summer squash relatives, such as zucchini, winter squash varieties should not be harvested until they have fully matured. Harvesting too soon will result in
produce that shrivels up and lacks flavor. Mature winter squash can be stored longer as well.
Mature winter squash will have a hard rind that cannot be easily sliced with your fingernail and the color will be deeper. To harvest, cut the squash away from the vine leaving about two inches of stem attached to the fruit. Handle the squash with care to
avoid damaging the rind. Any winter squash that has a damaged rind or is harvested without a stem attached will not store well and should be used soon after harvest.
Winter squash should be stored in a cool, dry area. For the best air flow and to prevent rot, store in a single layer and avoid allowing the fruit to touch.
FLOWERS
Hydrangea Blooms
If you are having trouble getting blooms from your established hydrangea plants there are several possibilities of why this is happening.
Bigleaf hydrangeas prefer light shade/filtered sun. Too much shade can hinder blooming. Too much sun can cause stress for the plant.
Pruning at the wrong time can remove buds for the next year and prevent blooming. This varies by species/cultivar so you need to know what type of hydrangea you are growing. Some cultivars develop buds on past season’s growth while others develop on new growth.
Well-drained soil is essential. Compacted soil can prevent the plants from receiving moisture even if you are providing enough water. Over and underwatering will impact flower development and plant health overall.
Too much nitrogen fertilizer will support leaf development but not flowers. Fertilizers with more phosphorus will support flower growth.
*** Winter temperature is commonly a problem with hydrangea blooms. If there is a cold snap and no snow insulating the plants along with inconsistent weather (unseasonably warm, followed by a freeze) the buds that developed in the fall can be damaged and this will impact the spring bloom. A late spring frost can also cause problems. If you think this is likely the problem, you can try wrapping the plants as we head into winter to provide some protection.
Your local extension agent can help diagnose further based on the historical weather data from your region.
PESTS
Description: Mimosa webworm larvae are about one-inch long and light green to gray/brown with five longitudinal stripes on the body. The adult moths are silver-grey and have small black spots on the wings.
Life Cycle: There are two generations of Mimosa webworm each year. The first-generation moths emerge in early June and lay eggs on the honeylocust leaves. Caterpillars can be seen from mid-June through early July. The second generation of moths appear in mid to late July to lay another round of eggs. The larvae from this generation feed from early to late August.
Damage: Though Mimosa webworms can defoliate trees, healthy, established trees tend not to suffer greatly. Damage is primarily aesthetic as the larvae create tight webs of silk around the leaflets. Foliage in the webs turns brown and is unsightly. Additionally, the silk hanging from the trees as the larvae lower to the ground is a nuisance.
Control: Chemical control is not typically necessary. Treatment is ineffective if applied this time of year when the webs and brown leaves are already present.
For more information about Mimosa webworm visit: KSRE Publication Mimosa Webworm
TURF
Kentucky Bluegrass Variety Selection for Cool-Season Lawns
Though Kentucky bluegrass is not as heat and drought tolerant as tall fescue and the warm-season grasses, it is commonly used in northeastern Kansas where there is sufficient annual rainfall. It is also grown under irrigation in northwestern Kansas where the higher elevation allows for cooler summer night temperatures.
Recommended cultivars for high-maintenance lawns and low maintenance lawns differ. High maintenance lawns are those that have irrigation to prevent stress and receive at least three fertilizer applications per year.
Lawns under a low-maintenance program may provide limited watering and fertilization.
Instead of the 4 to 5 pounds of nitrogen per 1,000 square feet per year typical of high-maintenance turf, a low maintenance program would include 1 to 2 pounds of nitrogen per 1,000 square feet per year. Obviously, a low input lawn will not be as attractive as a higher-input lawn, but you can expect the cultivars listed above to look fairly good in the spring and fall, while going dormant in the summer. A listing of both high-maintenance and low-maintenance cultivars can be found at the KSRE publication: Highest Rated Kentucky Bluegrass Cultivars for Kansas.
Recommended Tall Fescue Cultivars
Though several cool-season grasses are grown in Kansas, tall fescue is considered the best adapted and is recommended for home lawns. The cultivar K-31 is the old standby and has been used for years. However, there are myriad newer cultivars with improved color, density and a finer leaf texture. Most of these newer varieties are very close to one another in quality.
We recommend a regional blend of tall fescue cultivars that are commonly available in local garden centers and hardware stores. National blends such as those in big box stores often don’t perform well in Kansas as they frequently contain cultivars that don’t tolerate our stressful Kansas conditions. Pay attention to the percent “Crop Seed” and “Weed Seed.” Anything over 0.01% of either of these is not recommended.
Though K-31 may still be a good choice for large, open areas where weeds and a lighter green color can be tolerated, the new cultivars will give better performance for those who desire a high-quality turf.
QUESTION of the WEEK
Any idea what is going on with these coneflower blooms?
This growth is called “Aster Yellows”. It is a disease which can infect a wide range of ornamentals, weeds and even some vegetables, but the aster family is a common host. The disease is spread by sucking insects that feed on the plant and then travel to various food sources. The disease can cause deformed blooms, chlorotic leaf tissue between veins, mottled leaves and flowers as well as stunted or irregular growth. In the photo on the right, you can see deformed blooms as well as discolored leaf tissue indicating aster yellows is the cause.
Another problem that can cause deformed blooms is the coneflower rosette mite. Symptoms of this problem can look similar to aster yellows, though aster yellows affects the entire plant. Rosette mite is focused on the bloom. The mites live and feed inside the developing bud depleting it of nutrients.
For either one of these issues, the best treatment is to remove and destroy the infected plant material. For aster yellows it is especially important that even the root system is destroyed to prevent the spread to other hosts.
Contributors:
Cynthia Domenghini, Horticulture Instructor
Raymond Cloyd, Horticultural Entomology/Integrated Pest Management Extension Specialist
Jack Fry, Turfgrass Science Extension Specialist
Division of Horticulture
1712 Claflin, 2021 Throckmorton
Manhattan, KS 66506
(785) 532-6173
For questions or further information, contact: [email protected] OR [email protected]
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K-State Research and Extension is committed to making its services, activities and programs accessible to all participants. If you have special requirements due to a physical, vision or hearing disability, or a dietary restriction please contact Extension Horticulture at (785) 532-6173.
Cynthia Domenghini, Ph.D.
Instructor, Horticulture and Natural Resources
Kansas State University
[email protected]
