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GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published September 18, 2016

This summer was not as hard on area lawns as the past three preceding excessively hot summers, but many area lawns could still benefit from a little attention this fall.

Fall is the most important time of year for fertilizing your lawn. Applications of fertilizer in early September and again in late October to early November are the two most important times of year to fertilize your lawn. Even though grass top growth slows during the shorter, cooler days of fall, grass plants continue to grow sideways by producing tillers that become new grass plants. By fertilizing in late fall, you promote the production of healthy tillers that will result in a denser turf next year.

Fall mowing practices are key in protecting the health of those new tillers that are being formed in the fall. Keep mowing your lawn at the recommended height of 2.5 to 3 inches until top growth slows. After top growth slows to a stop, Kelly Kopp, Utah State University turf grass specialist, recommends gradually lowering the height of the lawn to about 1.5 inches. Leaving lawn grass extra-long in the fall can lead to fungal disease problems over the winter. Cutting the grass very short all at once will damage the established grass plants and the new tillers. Be sure to lower the height gradually.

When it comes to fertilization, lawns do not need a specialized “winterizing” fertilizer containing higher levels of potassium and phosphorus, despite advertisements seen at this time of year. No research indicates that these fertilizers are beneficial to the cool season grasses used for area lawns. When applying fall fertilizers you should be concerned primarily about nitrogen. The last application of fertilizer in early November should have most of the nitrogen in a quick-release form that is readily available to the grass as it begins to go dormant with cold weather. Kopp points out that research shows that late fall fertilization “provides the most benefit and drought tolerance to the lawn the following summer.”

Last year’s heat and drought left many lawns vulnerable to invasion from broadleaf weeds. Prostrate spurges have taken hold in numerous area lawns. These spurges have tiny leaves and form dense, ground-hugging mats. Spurges get started along lawn edges next to pavement or in open spots. Each plant is prolific, producing thousands of seeds. Seeds germinate in early summer, grow quickly, and flower within five weeks of germination. This provides time for more than one generation per year. The good news is that spurges are annual weeds and will die out with frost. Fertilizing and mowing to promote a dense turf will help crowd out the spurges next year.

During the growing season, spurges are difficult to control with herbicides because they are resistant to the typical dandelion broadleaf weed killers containing 2,4 D. The spurges are more effectively controlled with lawn weed control products containing triclopyr. Pre-emergent herbicides applied prior to germination in both lawns and landscape beds can also help in the fight against the spurges.

A fall application of a broadleaf weed herbicide will control most other perennial broadleaf weeds in lawns, such as dandelions, plantain, clover, black medic, and others. The results of a fall herbicide application is often not immediately apparent, but by next spring most of these weeds will disappear. However, there is no need to treat your entire lawn if you only have a few weeds. Treat these individually or pop them out with a weed popper.

Remember, a little attention to your lawn this fall will pay off next spring.


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written March 6, 2016

There are two main types of grassy weeds in home lawns, annual ones that come up from seed every year and perennial ones that persist from year to year growing from roots and runners that survive the winter cold. Controlling grassy perennial weeds in a lawn is a very difficult challenge. There are few, if any, chemicals available that will effectively kill the offending grassy perennial weed without harming the desirable lawn grasses.

One of the most hard to control perennial grassy weed is Bermudagrass. Bermudagrass is commonly planted in warmer parts of the country as a lawn and pasture grass. However, in our region it is considered a nasty aggressive and invasive weed in lawns and gardens. As a warm-season grass, it goes dormant during the cool months of winter and does not start growing actively until warmer months. It has tough wiry rhizomes (runners beneath the soil) and stolons (runners above the soil). It is sometimes confused with crabgrass because their seed heads are similar, but crabgrass is an annual that sprouts from seed every year and does not have tough persistent rhizomes or stolons.

Certain poor lawn care practices can encourage Bermudagrass. To avoid helping this dastardly weed, do not fertilize during the warmest months of the summer. This is the time of year when Bermudagrass is actively growing and fertilization at this time helps it grow even more. Abstain from frequent shallow irrigation and mowing short, practices that also promote Bermudagrass growth.

However, even the best of lawn care practices will not get rid of an existing infestation. If you can not tolerate this heinous weed taking over your lawn, you will need to consider using herbicides for management. In the last few years fenoxaprop, an herbicide, has become labeled for use by home owners for “suppression” of Bermudagrass. “Bayer Advanced Bermudagrass Control for Lawns” contains fenoxaprop.

It is important to note that suppression is the key word here. Fenoxaprop does not kill Bermudagrass outright, it only slows its growth. As noted on the label, using fenoxaprop to manage Bermudagrass involves repeated applications (every four weeks throughout active growth) over one or more years. Late application or missing just one application will significantly impair the chemical’s effectiveness. Proper timing of applications should be accompanied with lawn care practices that do not encourage Bermudagrass.

Of course, you could decide to “nuke” it and kill all the Bermuda grass along with your lawn grass so you can start over with a clean slate. However, even an application of the non-selective herbicide glyphosate (also known as Roundup, Impede, Knockout, and other trade names) is not a silver bullet. Bermudagrass is so tough that it will probably take several applications or more, spaced four weeks apart to kill this fiendish weed. (Glyphosate is should be applied when the Bermudagrass is green and actively growing.) Plus, once it appears dead and you till the ground, you should wait about two weeks or so to see if it any Bermudagrass begins to regrow and treat again if it does.

Warning! Common Bermudagrass does a good job of producing seed so even if you kill the existing perennial plants, it leaves behind plenty of seed that is viable for two years or more. If you are lucky enough to get Bermuda grass under control, it can easily re-invade the lawn from seed. Always watch for new patches starting to grow. Remember, I said perennial grassy weeds are difficult to control. In a couple of weeks we will talk about creeping bentgrass, another frustrating perennial grassy weed.

GARDEN NOTE: It is interesting to note that there are now improved hybrids of Bermudagrass available for planting lawns in the warm regions of the country. These hybrids have finer textured leaves, a darker green color, and they do not produce seed.


GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published February 28, 2016

It would be wonderful if new weed-free lawns could stay that way forever. Right? However, weeds “get their foot in the door” when lawns are subjected to stress from the environment or poor management practices, including watering, mowing, and fertilization. However, weeds will eventually show up in lawns as they age, even in ones that are well maintained.

Much has been accomplished in the field of weed science for the control of broadleaf lawn weeds, like dandelions and clover. Whether chemicals are utilized or removal by persistent pulling or digging is employed, most broadleaf weeds in lawns can be controlled relatively easily.

Grassy weeds are a different story. It is difficult to pluck out most grassy weeds from a lawn interspersed with regular lawn grass. Using chemicals to control grassy weeds is difficult because many chemicals that will kill the grassy weeds will also kill lawn grass. Before you can begin to consider using chemicals to control grassy weeds in your lawn, you need to understand how grasses grow.

There are two main types of grassy weeds, annual and perennial. Annual grasses die and come up again from seed every year. Crabgrass and annual bluegrass are the two most common annual grasses that cause problems in our area lawns. Excessive watering, frequent shallow watering, and consistently mowing a lawn too short are practices that make it easier for crabgrass to get started in a lawn. Excessive watering and compacted soil are conditions favorable to annual bluegrass. Correcting these problems and making a lawn as healthy and dense as possible with proper maintenance makes it more difficult for both of these annual grasses to persist in a lawn.

Chemicals are available that can provide help in managing these two weedy annual grasses in lawns. Preemergent herbicides chemically prevent seed germination and are applied before the seed of the annual grasses have the opportunity to germinate and grow.

Crabgrass seed germinates in the spring and preemergent herbicides or “crabgrass preventers” are only effective if the application is made prior to seed germination. The right timing for an application of a crabgrass preemergent herbicide is when the soil temperature at a depth of one inch is greater than 55 degrees for at least a week. This typically occurs when the yellow-flowering forsythia bush has been in full bloom for a week or two.

While some annual bluegrass seed germinates in the spring, most of the seed germinates in early to mid-fall, growing rapidly during mild winter and early spring weather, flowering in the spring and summer and producing lots of seed. Preemergent herbicides applied before crabgrass germinates will not persist long enough to prevent most of the seed from germinating. However, preemergent herbicides applied in the spring for preventing crabgrass will discourage early germinating annual bluegrass seed. For effective control of annual bluegrass, a preemergent herbicide should be applied in mid-August.

There are also postemergent herbicides available to kill seedlings of crabgrass and annual bluegrass if a preemergent materials are not applied at the right time. However, these chemicals are only effective if the plants are relatively young and small. These materials have the potential to injure your lawn grass if not applied correctly, so be sure to read the label and follow the directions before use.


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written November 15, 2015

This past weekend when employing an ordinary garden rake to clean up the deluge of leaves that fell from my shade trees, I started thinking that there must be a better way. There must be some tools or gadgets that would make leaf cleanup less onerous.

While my inexpensive garden rake was doing a pretty good job, I wondered if there was a rake that could make the job even easier. I did a little research and came across the “Lee Valley Power Rake.” While “power” is in its name, the power comes from the gardener. This rake is designed to “glide back and forth across the ground” and only infrequently needs to be lifted, decreasing the stress on your back. Lee Valley points out that it does an impressive job raking leaves, grass clippings and yard waste. It has a 5′ fiberglass handle and a 24″ wide head made of high strength plastic. It is available exclusively from Lee Valley ( I may give it a try.

If I was a little less energetic, I might be tempted to seek out the self-propelled Bosch ALR 900 Electric Lawnraker. This is machine looks like lawn mower and has a 900W electric powerdrive motor. It folds for storage. A review on a British website says it is “suitable for small, medium, and large gardens.” Beneath the raker is a rotating 32 cm wide plastic drum that holds replaceable metal tines. When set at the highest setting, the tines rake up lawn debris that gets sucked into the 50 liter collection box at the back of the raker, much like a bag on a mower. Set at lower settings, the raker will remove lawn moss and thatch.

The review recommends the raker, indicating it has adequate torque to handle the tough jobs. However, I do not think it is for me because I suspect I would be emptying the relatively small collection box, a little under 2 cubic feet, every couple of minutes or less with all my leaves!

I will still need to rake my leaves the old-fashioned way. The real problem is picking them up after raking them into piles. My hands are pretty small, making each “pick-up” quite paltry. However, I do use two plastic dustpans to scoop up the leaves, making each scoopful more worthwhile. There are manufactured leaf scoops or claws designed specifically for picking up leaves. I like the looks of the Releaf Leaf Scoops that are ergonomically designed large plastic “claws” with large internal handholds and scoops at the tips. They tout that they turn little hands like mine into big bear paws. Super!

When cleaning up leaves or other yard waste, another great gadget is the Fiskars 30 Gallon (22-inch diameter) Hard Shell Bottom Kangaroo Garden Bag. This is a pop-up container made of canvas-like polyester. It has a hard plastic bottom and handles that make it easy to drag or haul around the yard. When picking up yard waste that is not going to be composted, I line the bag with a 30 gallon garbage bag. When its work is done, the garden bag easily collapses and stores flat. You can find a variety of leaf scoops and pop-up lawn bags, as well as the lawnraker at

Okay, I have procrastinated long enough. I must go tackle the rest of my leaves.


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written October 25, 2015

I occasionally get asked to give a presentation on “putting the yard and garden to bed for the winter.” Fall garden chores are pretty simple and can be designated as “should-do” and “good-to-do”. I am not sure I could give a thirty minute or longer presentation, but here are the “should-do’s” for fall.

RAKE LEAVES: On the should-should do list is raking leaves. If you have a number of trees like I do, the leaves can certainly pile up. They tend to blow around and pile up at my back door and elsewhere in the landscape. As we start to get more dew and moisture, these leaves can mat down and smother the grass and other plants. Get those leaves raked up and consider using them for making compost or tilling them into your vegetable garden soil where they will decompose over the winter and help improve the soil.

MOW THE GRASS: After the stress of a very hot summer, your lawn needs all the help it can get. You should keep mowing if the lawn is growing. Do not mow the grass extra short and then put the mower away. Also, do not leave it extra long, as this can lead to matted grass and favorable conditions for snow mold. (This past spring snow mold fungus showed up in many area lawns and caused significant damage.) Mow at the recommended height of about 2.5 inches until you no longer need to mow. The good news is that as the weather cools, you will not need to mow as often.

TREAT FOR BROADLEAF WEEDS: If broadleaf weeds, like dandelions or clover, have shown up all over your lawn, now is the time you should treat for these weeds with an herbicide spray. However, if you only have a few of these weeds here and there, dig them out by hand or pop them out with a “weed popper.”

Herbicide sprays for broadleaf weeds will not control grassy weeds. Annual grasses, such as crabgrass will die with a hard frost, and need to be controlled next spring with pre-emergent herbicides or “preventers” that will keep the seed from germinating and growing. Perennial grasses, such as Bermuda grass, are not controlled with fall chemical applications.

DIG TENDER BULBS: Many of the tender bulbs, corms, rhizomes, and tubers that we plant in our gardens, including cannas, calla lilies, gladiolas, and dahlias, are tropical plants from warmer climates (Zones 7 to10) where they can stay in the ground over the winter. In cooler climates (Zones 6 and lower) like ours, they should be dug each fall and stored for the winter in a cool, dry protected location where they will not freeze. Some years in our area these tubers and bulbs may survive if left in the ground and heavily mulched. However, if winter brings severely cold temperatures, they will be killed.

To store them, wait about two weeks after frost kills their tops and then carefully lift the tubers, rhizomes or corms from the soil; shake off as much of the soil as possible; rinse them with clean water; and let them dry in a protected dry spot. Place them in cardboard boxes or paper bags using dry sawdust, wood shavings, or peat moss for packing.

You know, maybe I could give a talk on getting your yard and garden ready for winter. There seems to be a lot to do in the fall. More soon on the “good-to-do” fall garden tasks.


GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written September 6, 2015


This summer was tough on many area lawns, especially those where watering was restricted. Owners of ravaged lawns are wondering what to do now.

The first thing to do is assess the damage. Are spots and areas truly dead or did the grass just go dormant? With cooler weather and more water available, dormant grass should be starting to show signs of life. Check the brown areas closely looking for new grass blades. Once water becomes available, grass that is dormant greens back up within two weeks.

If no green growth is apparent and patches are a crispy yellow-brown or a grayish color, it is likely the grass is completely dead. Fall is a good time to re-seed or re-sod those areas, as long as irrigation water is available.

Because it takes some types of grass seed, like that of Kentucky bluegrass, up to two weeks to germinate, seeding must be done early enough to allow time for the seed to germinate and grow mature enough before hard frosts occur and before irrigation water is turned off. The average date of the first hard frost in this area is October 15th (note this is only an average date), so lawns must be seeded in early September. Re-sodding can be done later in the fall, as long as water is available and the soil is not frozen.

Water is critical to the success of both re-seeding and re-sodding. The soil must be kept moist to enable germination and provide moisture for root growth. If water is not available, you will be wasting time and money.

If more than 50 percent of your lawn is dead, you will probably want to consider complete renovation. You must get rid of the dead grass and any thatch before you can re-seed or re-sod. Seed and sod roots must be in touch with bare soil. Do this by mowing as low as possible and then using a rake, dethatching machine, or sod cutter to remove grass and thatch. Once you have bare soil, apply a starter fertilizer and the seed at the recommended rates on the labels and then rake the seed into the top of the soil.

If “only” 25 to 50 per cent of your lawn is dead, complete renovation can be avoided with over-seeding. First mow the lawn at a height of one and a half inches. Then you will need to rent a machine called a slit seeder or find a lawn care company who can come in and do this for you. The slit seeder cuts down through the grass and thatch and into the soil, dropping grass seed into the slit it creates. If you do this yourself, make two passes over the area in opposite directions. Check to make sure the seed is ending up planted at least 1/4 deep in the soil. Finish up with an application of lawn starter fertilizer and a light raking.

Next, moisture is needed to promote the germination and growth of the seedlings. This can be tricky as you need to water frequently enough to keep the soil moist but not too wet. Excess moisture can lead to disease problems. Once the grass germinates and plants develop several leaves, you should water more deeply and less frequently.

For lawns that survived the heat and are still green and growing, fall is the best time to fertilize. Apply fall lawn fertilizer in early September and again in early November.


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published- JULY 18, 2014


It’s getting downright ugly out there. I am talking about the brown spots and large areas of lawn turning brown. It is unsightly, but it is not a surprise. There are a variety of possible causes for this blighting of our green grass but watering, other lawn care practices, and weather are at the root of the problem.

Despite the watering wisdom of ‘watering deeply and less frequently,’ most area lawn owners have not opted to follow this sage advice that I offer year after year… after year. I talked a little earlier this season about watering when plants need it, not by relying on a timer that is set at the beginning of the season and never adjusted.

This year we experienced extended cool spring weather. That did not keep the irrigation timers from being set as soon as water was available with the typical 20 minutes per day. Because of the cooler weather, grass remained wet for considerable lengths of time setting up the perfect conditions for damaging lawn fungi to attack.

Pythium may be one of the fungi causing problems. Pythium fungi attack and kill the roots and crown of the grass plants. During cooler weather the disease may start as small yellowish patches that coalesce into larger areas. When it turns warm the disease show up as large areas of wilted and dying turf.

This disease can be avoided with ‘deep, infrequent watering’ and irrigating early in the morning instead of late at night. To reduce spreading the disease, collect and remove grass clippings when you mow. Remove excessive thatch and do not fertilize heavily during warm weather.

Thatch, another topic I have covered numerous times, may also be one of the problems contributing to lawn ugliness. Thatch is an intermingled layer of organic matter that comes from the grass plant itself. It consists of undecomposed grass stem, crown, and root debris. Thatch is not caused by an accumulation of grass clippings as once thought. It results when the grass produces this material faster than it decomposes.

Lawns in our area are predisposed to develop thatch because our soils, especially sandy soils, are generally low in microbial populations responsible for breaking this organic matter down. Plus, most of our area lawns are comprised of Kentucky bluegrass and fine fescue grasses that form more thatch than bunch-type grasses, like turf-type perennial ryegrass.

Many poor lawn care practices encourage the buildup of thatch and discourage microbe populations. Frequent shallow irrigation promotes thatch. Excessive nitrogen fertilization makes grass grow faster and develop thatch at a quicker rate. Infrequent mowing encourages the development of stem tissue and more thatch. Excessive irrigation and compacted soil discourage microbe activity.

The best defense against thatch is good preparation of the soil before seeding or sodding a lawn, followed by sound lawn care practices. This includes deep, infrequent watering; mowing regularly at the recommended height; fertilizing at recommended rates; aerating to relieve soil compaction; and removing thatch when the layer exceeds one-half inch.

Finally, another common cause of large brown spots in lawns during this hot weather is sprinkler coverage. Check how much water is being applied to the brown areas when the sprinklers are on.

Speaking of water, be sure to drink plenty of it when you are gardening outside.

Published: 7/18/2014 11:38 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published- AUGUST 29, 2014


This has been a banner year for crabgrass in home lawns, including mine. About a month ago I noticed patches of this bright green annual grass sticking out like sore thumbs all over the front lawn. Oh no!

We had not had a big problem with crabgrass in the past so we did not apply a pre-emergent herbicide in the spring to prevent its germination. However, even folks who did apply ‘crabgrass preventers’ at the recommended time are finding this weedy grass in their lawns this year.

Before we talk about what to do about it, let’s review. There are actually two different species of crabgrass found in our area, smooth crabgrass (Digitaria ischaemum) and hairy crabgrass (Digitaria sanguinalis). Native to Eurasia, they do exceptionally well here, germinating from seeds in the spring, growing rapidly during the heat of summer, flowering, setting seed, and then dying out with frost in the fall. They produce copious amounts of seed capable of germinating the following spring or in future springs.

Smooth crabgrass is most common in area lawns. When first noticed in lawns, it is light green. As the plant grows, it turns a darker dull green and forms flattened clumps. Its seeds are produced from August to September on flower stalks with finger-like spikes, resembling the those of Bermuda grass.

So why such a bad outbreak in home lawns this year? I suspect it is due to the weather. In lawns where ‘crabgrass preventer’ was applied at the recommended timing, the chemical control may have partially dissipated by the time the weather started to warm and the crabgrass germinated. Because of this year’s long spring, some of these products may have needed to be reapplied to extend the period of control.

Our long, cool spring was almost immediately followed by extended very hot weather. A warm-season grass, crabgrass loves the heat, but our cool-season lawn grasses virtually stop growing in hot weather. Plus, lawn grasses can be further stressed by poor cultural practices, like mowing, watering, and fertilization.

So what can we do now? Healthy dense turf is one of the best ways to combat crabgrass next year. Scalping your lawn (taking off more than 1/3 of the leaf blades at one time) or regularly mowing too close weakens turf. Mow your lawn no shorter than 2.5 inches, mowing frequently enough so you don’t scalp the lawn.

Water your lawn deeply when you irrigate. Avoid frequent daily light irrigations which encourages shallow-rooted grass, the development of thatch, and promotes crabgrass germination and growth.

Fertilize your lawn at the right times to promote dense, healthy turf. Apply 4 pounds of nitrogen per 1000 square feet every year, applying one pound on September 1, November 1, May 1, and June 15. On sandy soils, consider using fertilizers with a percentage of nitrogen in a slow-release form.

If you have a crabgrass problem now, be sure to apply a crabgrass preventer next spring when the soil temperature (at a depth of one inch) is greater than 55 degrees Fahrenheit consistently for a week. That is usually about the time when the yellow flowering forsythia has been in bloom for several weeks. It is also important to apply the ‘preventer’ evenly across the lawn, taking care not skip areas.

Next spring is a ways off, so keep this information handy until then.

Published: 8/29/2014 11:33 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published April 18, 2014


At this time of year, many homeowners are asking about crabgrass control and basic lawn care. Is it too late to apply “crabgrass preventer?” When should I fertilize? How often should I be irrigating?

Let me take a little time to address these queries, but first we need to determine if the offending grass is truly crabgrass? Many homeowners think they have a crabgrass problem, but what they actually have is a Bermuda grass problem.

Crabgrass is an annual that comes up from seed every year and dies with frost in the fall. Bermuda grass is a perennial that comes back from its tough, wiry trailing stems and rhizomes (underground stems) every year. It’s leaves are blue-gray in color, where as crabgrass leaves are green. While not similar in appearance, these two grasses are often confused with each other because they have similar seed heads.

Best Management Practices for a Healthy Lawn: Your first line of defense against crabgrass should be encouraging healthy, dense turf using good cultural practices. This includes mowing, fertilizing, and irrigating properly. Mow bluegrass and bluegrass mix lawns at the WSU recommended height of 2 to 2.5 inches. A dense, tall turf shades germinating crabgrass seedlings and deters their growth.

Equally important in controlling crabgrass is fertilizing your lawn at the correct times of year to promote both root and side growth (called tillering) instead of top growth. The most important time of year to fertilize your lawn is in the fall. WSU recommends making a fertilizer application in early September and again after the last mowing (around mid-November) but before the soil freezes.

If you apply fertilizer in the fall as recommended, then you should wait until early May to fertilize again. Fertilizing earlier in the spring tends to encourage top growth at the expense of root and side growth, resulting in weaker turf and more frequent mowing. The best times to fertilize lawns in our region are: November 15, May 1, June 15 and September 1, applying 1 pound of nitrogen per 1000 square feet of lawn area.

When irrigating lawns, the tendency in our region is to water daily starting early in the season for 15 minutes each day. This daily, light irrigation leads to weaker, shallow-rooted, thin turf and makes it easy for crabgrass to germinate and grow. You will have to water more frequently during the hottest part of summer, but during the relatively cool weather of spring and fall you should definitely not be watering daily. Adjust your timers to water less frequently, but more deeply to promote deeper grass roots.

Chemical Crabgrass Control: There are a number of home garden products often called “crabgrass preventers” that contain herbicides that are applied in the spring prior to crabgrass seeds germinating to prevent them from sprouting and growing. The general time to apply these products is when the soil temperature reaches about 62 degrees at a depth of 1 to 2 inches or about two weeks after forsythia blooms start to drop.

There are also some home garden products (containing dithiopyr or fenoxaprop) that will kill very young crabgrass seedlings after the seeds germinate, although their effectiveness tends not to be as reliable as good turf management and the use of “preventer” products.

The lawn care season is starting. Homeowners who use recommended “best management practices” will have healthier lawns and fewer problems with crabgrass.

Published: 4/18/2014 11:45 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published 9/6/13

As the garden season winds down, many gardeners may be thinking it is time to relax. It is not. Now is the time to make a checklist of fall gardening chores that should be done before fall’s end.

First on the list should be fertilizing the lawn. Early September and late October are the two most important times of year to fertilize your lawn. During the hot part of summer cool season grasses become stressed. Grass shoot and root growth slows to a stop. As the weather cools in fall, the grass begins to grow well again, establishing new roots and putting on sideways growth that increases lawn thickness. Nitrogen applied in the fall helps the grass recover from the stresses of summer.

Fertilizer applied now helps stimulate shoot growth. A late fall fertilization, applied after the grass stops growing, promotes root growth and the storage of food reserves needed for spring growth. This late fall application also keeps the grass looking greener through the winter and you should not need to fertilize again until April or May.

WSU recommends using a top-quality lawn fertilizer that contains some slow-release or controlled-release nitrogen, such as IBDU, sulfur-coated urea, or urea formaldehyde. These fertilizers release nitrogen over an extended period of time and allow for more even growth during the growing season. Fertilizers with soluble nitrogen, such as ammonium sulfate or urea, with nitrogen in a quickly available form are best for late fall fertilization.

Next on your list should be taking care of lawn weeds. If you just have a few weeds here and there, take them out with a weed digger. If the problem is more serious, you may want to consider the application of a broadleaf weed killers. October is a good time for applying these materials.

For weeds like black medic, bindweed, mallow, dandelions, plantain, and clover a combination herbicide product containing 2,4 D and MCPP should provide good control. A lawn product containing triclopyr will help with tough-to-control broadleaf weeds, like oxalis, prostrate spurge, henbit, ground ivy, and lawn violets. As with any pesticide product, be sure to read and follow label directions.

Now is also a good time to order or purchase spring flower bulbs for planting next month after the weather cools. Keep in mind that bigger (more expensive) bulbs produce bigger flowers. If your bulbs are packaged in a plastic or closed paper bag take them out and place them in an open well ventilated tray located in a cool (50 to 60 degrees Fahrenheit) spot.

Wait to plant the bulbs until the soil temperature drops below 60 degrees Fahrenheit. This temperature allows for root growth without stimulating leaf growth. Don’t forget the bulbs need water, so water them in right after planting and whenever needed during mild fall and winter weather to keep the soil slightly moist.

Other tasks to put on your list include:

raking up leaves

building a compost pile

dividing spring and early summer flowering perennials that have become crowded

cutting back to the ground the dead tops of perennial flowers

weeding and cleaning away plant refuse in garden and landscape beds

aerating your lawn if the soil is compacted

giving all your trees, shrubs and perennials a good deep watering before the water is shut off for the season


Whew! That’s a lot of work. You and I should get busy.



Published: 9/6/2013 2:28 PM

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