University of Minnesota Extension
Menu Menu

Extension > Yard and Garden News > Archives > October 2012 Archives

October 2012 Archives

October 1, 2012 Issue

Greetings Yard and Garden News Reader:

In order for us to bring you the gardening news you want, we need to know your opinions, your interests, and your thoughts on the newsletter.

The survey takes between 10 and 15 minutes to complete.

Would you be so kind as to complete the survey by October 15.

The link below will take you to the survey.

Yard and Garden News Survey 2012

We thank you in advance for your time and thoughts!

Karl Foord, editor

Sam Bauer, Extension Turfgrass Educator

With rising economic and environmental concerns regarding the efficient use of fertilizers in urban settings, it becomes important to understand the role that late-fall fertilization plays in our lawn care program. Long-standing recommendations for late-fall nitrogen fertility involved the use of quick release nitrogen sources (urea, ammonium sulfate, others) to be applied after the last mowing of the year. The theory was that the nitrogen would be absorbed by the turfgrass roots prior to winter, but would not be utilized for growth until the following spring. While this theory seems reasonable, and generally results in a healthier lawn, the predictability of quick release nitrogen applications at this time is low.

Sam Bauer

Photo 1: U of MN grounds manager Jonathan Spitzer applies a 50/50 blend of quick release and slow release nitrogen sources to the St. Paul campus turf in late-September.

Collaborative research between the University of Minnesota and the University of Wisconsin-Madison has demonstrated that turfgrass absorption of nitrogen reduces as temperatures cool later into the fall. We refer to this as a reduction in turfgrass nitrogen use efficiency (TNUE). In climates that are conducive to a reduction in TNUE, as in the case with slow growth associated with late-fall temperatures, fertilizer applications have a greater potential to move off-site. This off-site loss is particularly concerning due to environmental and economic implications.

Consider the fact that the costs of producing nitrogen fertilizers have more than tripled in the last decade due to the rising price of fossil fuels used for nitrogen fertilizer production. Additionally, the Environmental Protection Agency has placed a 10 ppm nitrate standard on drink water. These are the driving factors for refining the late-fall nitrogen fertilizer recommendations, as we can no longer afford to make nitrogen fertilizer applications that have a high potential to move off-site.

The new recommendations can be summarized as follows:

- Make final nitrogen fertility applications no later than mid-October
- Combine quick release and slow release nitrogen sources when applying more than 0.5 pounds of nitrogen per 1000 square feet
- Only apply fertilizer to actively growing lawns, because TNUE reduces when growth is low

Phosphorus and potassium applications should always be based on soil test results. Soil testing information and submission forms can be found at the University of Minnesota Soil Testing Laboratory website:

For more detailed information regarding the use of home lawn fertilizers follow these links to a three part discussion from retired Extension Turfgrass Educator Bob Mugaas.

Understanding and Using Home Lawn Fertilizers- Part 1: The Basics

Understanding and Using Home Lawn Fertilizers- Part 2: Nitrogen

Understanding and Using Home Lawn Fertilizers- Part 3: Phosphorus and Potassium

Boxelder Bugs Are on the Move

Jeffrey Hahn, Asst. Extension Entomologist

It has been a long summer but fall is finally catching up with us. Fall is also the time when nuisance insects fly to buildings and other structures to look for places to spend the winter. One insect to be on the watch for is the boxelder bug Although these orange and black insects are around every year, they have been particularly numerous this summer. The weather has a lot to do with that as years of hot, dry summers are very favorable for their development and we often experience much larger populations of them then.

Jeff Hahn

Photo 1: A nemesis, the boxelder bug, is present in large numbers this year.

Right now a lot of people are finding large numbers of boxelder bugs on the sides of their homes. Being on the outside of structures is not necessarily bad if boxelder bugs would just stay there but eventually many of these insects will get inside these buildings. There are not any practical home remedies for dissuading boxelder bugs from landing on homes, although people have tried solutions such as throwing boiling water on them and trying to kill them with fly swatters. While people may not like all of the boxelder bugs on the outside, people should aim at preventing these insects from getting into their homes.

Control is two fold. First, seal as many spaces and openings as possible that may allow boxelder bugs into your home. Concentrate around widows and doors, roof lines, where utility lines enter buildings, and where horizontal and vertical surfaces meet. Second, supplement this with a residual insecticide application, especially around areas where boxelder bugs are most likely to gain access. This is something homeowners can try themselves; common active ingredients that could be used would include permethrin and beta-cyfluthrin (make sure products are labeled for the outside of homes). Or they can contact an experienced pest management service to make this application for them.

Not only is it important to take action now to keep boxelder bugs out of your home this fall but a lot of these insects can also become nuisances later during days of mild winter temperatures. Once they get inside, they seek out wall voids, attics and other nooks and crannies in which to hibernate. It is important for boxelder bugs to find a place that is unheated and will remain cold during winter. As long as they are in such place, they will remain dormant.

Jeff Hahn

Photo 2: Boxelder bugs looking for overwintering sites on a home.

However, as temperatures warm up the sites where boxelder bugs are hiding, they will wake up, 'thinking' spring has arrived. They will move towards the warmth and will end up being trapped indoors. Boxelder bugs typically aggregate in clusters; insects on the outer part of these clusters will become active first. This results in boxelder bugs emerging at different times. When boxelder bugs appear in the middle of the winter, it appears that they have been reproducing indoors, however what people are seeing are adults that entered their homes the previous fall. (Note: Boxelder bugs are occasionally observed laying eggs indoors. However, either immature boxelder bugs don't hatch from them or if they do the young bugs do not have food and do not live long. They certainly are not able to mature into adult bugs.)

The boxelder bugs that get inside your home can definitely be annoying; in fact the more there are the more bothersome they usually are. Fortunately, boxelder bugs are harmless to people. They may occasionally stain surfaces but are otherwise not damaging to property. Once they are in your home, you have few options to deal with them. The easiest solution is physical removal, such as with a vacuum cleaner. This may not always be helpful when boxelder bugs are really numerous, but that is still the best control. This is why the more you can prevent from entering your home during fall, the fewer you will deal with later.

Plant NOW for Dazzle next Spring

Karl Foord - Extension Educator, Horticulture

I always have mixed feelings about fall. I know plants, animals, and insects have cycles, but it is depressing to see the hummingbirds leave, the plants die or go dormant, and the insects die or hibernate. In the spirit of acceptance of such things I would choose to focus on the spring when many things "come back" to life. One of the great joys of spring is watching the spring flowering bulbs pop through the ground and bring color to a bleak landscape. To enjoy this one must act now and plant. To appreciate the joys to come I have collected the Flowering Plant Video Library entries featuring spring flowering bulbs and organized them by flowering time somewhat following Chart 1. which also appears in the yard and garden brief: Spring Flowering Bulbs.

Y&G Brief

Chart 1: Spring Flowering Bulbs Planting Chart

General Recommendations:

1. Plant in odd numbered groups or mass plantings.
2. Plant where they can be seen from a favorite window in the house.
3. Planting depth and spacing depends on the individual bulb. Generally bulbs are planted 2.5 times their diameter. In light sandy soils plant 1 - 2 inches deeper and in heavy clay soils 1 - 2 inches more shallow.
4. Protect bulbs from hungry critters

See articles below for specific bulbs.

Plant Some Early Spring Flowering Bulbs

Karl Foord - Extension Educator, Horticulture

Click on the link to see the video with host Dr. Mary Meyer, Professor of Horticulture

Karl Foord

Photo 1: Striped Squill (Puschkinia scilloides var. libanotica)

Striped Squill (Puschkinia scilloides var. libanotica)

Karl Foord

Photo 2: Snowdrops (Galanthus nivalis)

Snowdrops (Galanthus nivalis)

Karl Foord

Photo 3: Siberian Squill (Scilla siberica)

Siberian Squill (Scilla siberica)

Karl Foord

Photo 4: Glory of the Snow (Chionodoxa luciliae)

Glory of the Snow (Chionodoxa luciliae)

Karl Foord

Photo 5: Checkered Lily (Fritillaria meleagris)

Checkered Lily (Fritillaria meleagris)

Karl Foord

Photo 6: Species Tulips (Tulipa tarda)

Species Tulips (Tulipa tarda)

Karl Foord

Photo 7: Garden Hyacinth (Hyacinthus orientalis)

Garden Hyacinth (Hyacinthus orientalis)

Karl Foord

Photo 8: Grape Hyacinth (Muscari armeniacum)

Grape Hyacinth (Muscari armeniacum)

Karl Foord - Extension Educator, Horticulture

Click on the link to see the video with host Dr. Mary Meyer, Professor of Horticulture

Karl Foord

Photo 1: Triumph Tulip (Tulipa 'Gavota')

Triumph Tulip (Tulipa 'Gavota')

Karl Foord

Photo 2: Daffodils(Narcissus spp.)

Daffodils (Narcissus)

Karl Foord

Photo 3: Ornamental Onions (Allium spp.)

Ornamental Onions (Allium spp.)

Sam Bauer, Extension Turfgrass Educator


A resounding sigh of relief was felt over much of the state as July passed. It was the second hottest July on record in Minnesota, and the hottest in 118 years of records throughout the rest of the country. Precipitation around the state varied greatly. From record droughts in northwest and parts of southern Minnesota, to record floods in the northeast, this summer was anything but typical. Homeowners in the Twin Cities metro should feel very fortunate to not be dealing with the after-effects in these areas. Still, if you were able to sustain the quality of your lawn throughout July, it was truly a blessing.

August came and went fairly quickly with very little love from Mother Nature, almost a three inch rainfall deficit in the Twin Cities. The map below from the MNDNR State Climatology Office puts precipitation deficits into perspective across the state from July 31st to September 24th.

MNDNR Climatology

Photo 1: Precipitation Map for Minnesota

September ended with only 0.3 inches of rainfall recorded in the Twin Cities. In fact, it was the second driest September on record. Central and northeastern Minnesota suffered the worst. What implications does this have on your fall lawn care practices? I'm glad you asked.

Fall is the preferred time for many important lawn care practices. From fertilization and weed control, to cultivation and seeding, there is absolutely no better time for cool-season turfgrass maintenance in the Midwest. But this year is different. The lack of precipitation in August and September has caused many of our Kentucky bluegrass, perennial ryegrass, or fine fescue lawns to brown out and cease growing, almost a revert back to summer dormancy for those homeowners that lack the availability of adequate irrigation. In order for your lawn to recover, you will need to begin irrigating regularly. This means more than just one or two cycles, but enough water to wet the root zone sufficiently to sustain turfgrass health.


Speaking of turfgrass health, if your lawn is stressed from lack of moisture, typical fall maintenance practices that we have recommended in the past will add additional stress. In this case, we might actually see our lawn quality decline from the practice, for example: aerating.

The best advice that I can give you is to determine the growing conditions that are furthest from optimum and correct those first. If your lawn is declining from a lack of moisture, irrigate. If you've been irrigating with little turfgrass response, soil compaction may be an issue, in which case aerating would help. Has your fertility program been adequate? Are there insect or weed pressures? These are all questions to consider.
Concentrate more this fall on creating the best possible growing environment for your turfgrass, and you will reap the benefits during next year's growing season. Adding turfgrass stress to an already stressful situation will do more harm than good.


Return adequate soil moisture levels and turfgrass health before you conduct these practices.


• Aerate. While aeration is a great fall practice, it places stress on the turfgrass plant and may actually cause the lawn quality to decline.

• Dethatch or vertical mow. This process tears turfgrass leaves and crowns, and should only be conducted when the lawn is healthy.

• Spray herbicides. Systemic and contact herbicides used for weed control are more effective when weeds are actively growing.

• Fertilize with quick release nitrogen. High rates of quick release nitrogen fertilizers can have negative effects on drought-stressed turf. There is also a greater potential for environmental loss of nitrogen when the lawn is not actively growing.

• Mow too often or too low. Raising the mowing height and mowing less frequently will help encourage turfgrass recovery.


• Maintain soil moisture to promote turfgrass recovery.

• Spot seed and fertilize thin and weak areas with a high quality turfgrass seed mixture.

• Fertilize with slow release nitrogen sources and soil test to determine fertilizer requirements of phosphorus and potassium.

• Aerate when the lawns health has been restored.


Karl Foord - Extension Educator, Horticulture

Click on the link to see the video with host Dr. Mary Meyer, Professor of Horticulture

Fireworks Goldenrod (Solidago rugosa 'Fireworks')

Karl Foord

Photo 1: Fireworks Goldenrod (Solidago rugosa 'Fireworks')

Karl Foord

Photo 2: Fireworks Goldenrod (Solidago rugosa 'Fireworks')

Rozanne Geranium (Geranium 'Rozanne')

Karl Foord

Photo 3: Rozanne Geranium (Geranium 'Rozanne')

Lesser Calamint (Calamintha nepeta)

Karl Foord

Photo 4: Lesser Calamint with Sweat Bee (Calamintha nepeta)

Karl Foord

Photo 5: Lesser Calamint with Honeybees (Calamintha nepeta)

Karl Foord - Extension Educator, Horticulture

Click on the link to see the video with host Dr. Mary Meyer, Professor of Horticulture

Giant Amaranth (Amaranthus cruentus)

Karl Foord

Photo 1: Giant Amaranth (Amaranthus cruentus)

Savannah Ruby Grass (Melinis nerviglumis 'Savannah')

Karl Foord

Photo 2: Savannah Ruby Grass (Melinis nerviglumis 'Savannah')

Russian Sage (Perovskia atriplicifolia)

Karl Foord

Photo 3: Russian Sage (Perovskia atriplicifolia)

Lesser Calamint (Calamintha nepeta)

Karl Foord

Photo 4: Lesser Calamint with Sweat Bee (Calamintha nepeta)

Karl Foord

Photo 5: Lesser Calamint with Honeybees (Calamintha nepeta)

Little Titch Catmint (Nepeta racemosa 'Little Titch')

Karl Foord

Photo 6: Little Titch Catmint (Nepeta racemosa 'Little Titch')

  • © 2014 Regents of the University of Minnesota. All rights reserved.
  • The University of Minnesota is an equal opportunity educator and employer. Privacy