Over the Fence Where gardeners come to find out what's happening out in the yard. Sun, 15 May 2005 13:02:08 -0500 https://web.extension.illinois.edu/dkk/eb192/rss.xml Landscape Mulch with Expectations https://web.extension.illinois.edu/dkk/eb192/entry_13420/ Wed, 13 Jun 2018 09:02:00 +0000 https://web.extension.illinois.edu/dkk/eb192/entry_13420/ By this time of the year, there has already been a lot of landscape mulch applied for the summer. Landscape mulch can provide more benefit than just how nice a freshly applied layer looks.

When applied around young trees, we know that it reduces the competition from grass and makes it easier for the tree to establish in the new location. The tree gets more water and has no competition for soil nutrients. A big plus is there is no need to trim grass away from the trunk saving the tree from the destructive string trimmer!

When mulch is applied at the recommended depth of two to three inches, once settled, the tree or plant also benefits from water conservation. Having mulched beds can make the difference of a plant being stressed or not. Stressed plants are more likely to attract insects and are more disease prone.

Another benefit is weed management. Those weed seeds are around, yet kept in the dark, so they remain dormant. For the few annual weed seedlings that do make it to the surface, they can be pulled easily. Getting the bed clean is always helpful. Get rid of existing weeds and leave the soil surface loose to more readily absorb water. There are those perennial weeds that will re-sprout, so be on the look out and get them out as soon as you see them by cutting them below the mulch layer or spot treating with a non-selective systemic weed control product. Be careful not to damage surrounding ornamental plants.

Our grasses typically grow towards our landscape beds, from two to four inches a year. Before you mulch, consider edging that bed. This is always a good time to consider any bed line changes as well. Consider the turning radius of the riding mower or the fact that perennials and shrubs are growing out farther than the existing bed line. The bed will look much better and more "relaxed." Another bonus of bed expansion is less grass to mow and the ease of mowing with the new bed line.

Nothing comes without problems and landscape mulch is no different. Organic mulch will immediately begin to decompose once applied and with that come some familiar and unfamiliar bits of nature. We easily recognize mushrooms, and understand they come from weather conditions where periods of rain and cool temperatures promote them. You can see mushrooms protruding up and out of the mulch.

Extension Master Gardeners often get calls of other "things" found on the surface of landscape mulches. Slime molds can appear in several colors and show up in hours or overnight. They have some common names being very descriptive of what they look like! Mushrooms and slime molds appear with the right conditions in the mulch and can be avoided or stopped when they do show up by loosening the mulch with a tined digger or landscape rack to dry out the mulch. Doing nothing is always an option, as those mushrooms and slime molds will only be there a few days.

Mosquitos in the Landscape https://web.extension.illinois.edu/dkk/eb192/entry_13416/ Mon, 11 Jun 2018 08:56:00 +0000 https://web.extension.illinois.edu/dkk/eb192/entry_13416/ Mosquitos are adjusting to our ever-changing weather patterns just like our plants in the home landscape this season. May into June would be our traditional time mosquitos start show up for the summer. This season, April had the rain and not May, so mosquitos can be behind a bit.

Mosquitoes favor warmer temperatures and the right kind of water – permanent, floodwater or stagnant, depending on the species. Permanent bodies of water include ponds and lakes. Floodwaters are retention ponds that are dry most of the time and natural low-lying areas. Stagnant water examples are those clogged gutters, garden structures that can hold water and bird baths.

When the water is cooler, development is slower and larvae will succumb to natural diseases, reducing the numbers that make it to adulthood. We have had the warmer temperatures recently but not the standing water or stagnant water so far. Permanent water mosquitos are not the ones that show up in large numbers.

Homeowners tackle mosquito management on a number of fronts. Not just for mosquito management, but cleaning and clearing the gutters for the next rain event will prevent water damage to the home too. You may wonder "How could a gutter be plugged up already?" yet spring bud scales and flower parts from our big trees can fill it quickly. If there are any parts of your yard art that hold water or parts that collect water, think mosquitos. If those areas dry out within a week, you are ok. Birdbaths should be flushed about one a week to prevent mosquito larvae from turning into biting adults and to provide clean water for the birds.

Gardeners also can incorporate some of the mosquito repelling plants into the flowerbeds. These help in the overall effort to reduce biting mosquitos, but alone, will not do the job. Plants like catnip, basil, scented geraniums and lemongrass will be advertised to repel mosquitoes and other insects.

Often the floodwater mosquito is the one giving us the large number of mosquitos about two weeks after a rain event. They are noisy, buzz around our face, can fly very well and can come from a good distance. So even with empty gutters and clean birdbaths, they can be very bothersome while we are outside.

Other options for mosquito management will be the use of clothing treated to repel mosquitoes, or applying a number of sprays or lotions that repel insects. These can be natural oils or synthetically based. They can be effective for as little as an hour or can last for several hours. None are likely to last the day with just one application.

Lastly, mosquitos are attracted to body heat, carbon dioxide and dark clothing. So, think twice when choosing your gardening outfit, as you don't want to paint a mosquito bullseye on yourself.

Water and Weeds https://web.extension.illinois.edu/dkk/eb192/entry_13397/ Wed, 30 May 2018 08:46:00 +0000 https://web.extension.illinois.edu/dkk/eb192/entry_13397/ Right now, there is plenty of soil moisture with all the recent rains. Even when the top of the soil seems dry, dig down just a little bit, and the moisture is there. Established plants are doing well as is the lawn. Gardeners will still be watering in any new transplants, trees, shrubs or evergreens; not because the soil is dry, but rather to settle the soil around the plants so roots do not dry out.

All the soil moisture that has the home landscape looking so good right now also encourages any perennial weeds, whether grasses or broadleaves, to grow vigorously too. In the lawn, Master Gardeners are answering questions on tall fescue and quackgrass for both identification and potential management. Since they are perennial grasses just like our preferred lawn grasses, options are limited to post-emergence products that will take out these grassy weeds right along with our lawn grasses. Gardeners have some good success managing tall fescue by digging out this bunch-type grass and reseeding or sodding the spot. This is not a good option for quackgrass, as it has a spreading underground root system.

Common broadleaved weeds in the lawn include dandelion, plantain, ground ivy (known as creeping Charlie) and more recently thistles. The first line of defense is getting and keeping the lawn competitive against these weeds. Treatment of the weeds and getting the lawn strong can be done at the same time. As the weeds fail, vigorously growing turf will fill in.

Of all the thistles, the worst one to manage is Canadian thistle. It spreads by underground rhizomes just like quackgrass. If you see several thistles "in a row," they are very likely coming up from the same below ground runner. Thistles show up in the lawn from areas that are not managed. If thistles are left to grow, they will produce seed and can spread that way too.

In the perennial beds, all of the above weeds can be present. Dandelions can be growing up in the crown, as that is where the weed seed was caught. It is common to see grasses growing up and out of the canopy of your perennials and dandelion from at the base at the same time. Once you decide it is time to clean that up, digging up the perennial at the right time and clearing the roots of the grassy weeds and taproot of dandelion before resetting is a good practice. This is also a good time to check for soil insects, such as the iris borer, if you cleaning up and dividing plants.

In the vegetable garden, every time you work the soil, you encourage a new crop of weed seed to germinate. If you do need to cultivate, do so very shallowly. You can exhaust the supply of weed seed after several times of shallow cultivation and then the canopy of vegetable plants will continue to shade the soil, further reducing weed seed germination. If you do need to water the vegetable garden, water the base of the plants or along the row. Watering the whole garden will encourage weed seed to germinate as well.

Edging and Mulching Landscape Beds https://web.extension.illinois.edu/dkk/eb192/entry_13382/ Mon, 21 May 2018 12:45:00 +0000 https://web.extension.illinois.edu/dkk/eb192/entry_13382/ Here we are, nearing the end of May. Maybe the beds in the backyard look OK, or maybe not? We love our lawns, yet grass can move into our landscape beds in a stealth-like manner while we are waiting for better weather for weeding and edging.

Putting a strong clean line on the landscape beds really makes a difference in how they look. It brings out the strong curves that make the bed flow through the yard, and that edge is the important transition from bed to lawn. Grass will grow towards and into the beds about 3 to 4 inches a year, so annual edging is quite beneficial.

With new plantings and a recently created bed, perhaps the best edging is a simple one made with an edging tool or flat spade. Too often beds are created, lined with an edging material that in a few short seasons can be found well underneath the evergreen and shrub branches at the ground because we did not realize just how much those plants are going to grow. Another good reason to hold off with any permanent edging is bed creation occurs over a few growing seasons and the bed edge should be able to change with it as well. Perennial flower beds come to mind as a great example. Increasing the number of plants with different bloom times and colors usually means a deeper bed out into the yard; easy to do if edging material does not have to be moved as well.

Bed lines that are too close to plants can make the bed look tight and confining. Opening up an established bed as the plants have grown and matured provides a relaxed view of the annuals, perennials and shrubs.

In addition, there are a variety of mulches that can be used in landscape beds to clean up the look. Naturally colored mulches will retain their color longer than dyed mulches. Mulches also can vary in size consistency. Mulches that are screened more than once show up more uniform once spread. You might consider using a higher quality mulch in those beds that are seen regularly and up close, compared to the back screening bed a good distance from the home.

Mulching flower beds can be a bit tricky, as many of our perennials grow each year from the crown of the plant and are not able push up through mulch. Be careful about mulching into the crown of those plants. Mulch is typically put down at about an inch deep, once settled, in flowerbeds, compared to landscape shrub and evergreen beds, where 2 to 3 inches is pretty common. When mulching to the lawn edge, if possible leave some open dirt. This makes touch up edging easy and keeps the grass from moving into the mulch too.

Managing Crabgrass Now for Next Year https://web.extension.illinois.edu/dkk/eb192/entry_13354/ Mon, 07 May 2018 11:30:00 +0000 https://web.extension.illinois.edu/dkk/eb192/entry_13354/ Relying on chemical crabgrass preventer is just one strategy homeowners can employ to reduce the potential of crabgrass in the home lawn. Crabgrass preventers also will prevent other annual grassy weeds, like the foxtails, and a few broadleaved weeds, like annual chickweed. These products are reliable and will do the job as advertised, as long as the products are applied in a timely manner.

Crabgrass will germinate in the spring as soon as the soils warm consistently to the 55 to 60-degree range for a 7 to 10 day period. This spring, this has not been easy to figure out. Some of our usual indicator plants are not helping us this year either, and a soil thermometer always provides a more accurate picture. A crabgrass preventer will need to be applied early enough to catch the crabgrass seed as it begins to germinate. If put on too late, you still get some control though, because crabgrass seed will continue to germinate as temperatures climb into the 90s. However, the earliest of the seed will have had the opportunity germinate and show up in the lawn.

One of the best cultural practices you can do this year, and every year in the future, is mow more often while the lawn goes through the natural spring flush. Frequent mowing does not stress the grass plant as you are only removing a small portion of the grass blade, keeping it competitive with any weeds. The goal is to remove no more than 1/3 of the grass blade at any mowing. While the lawn flushes out in the spring, mowing may need to be done every 3 to 5 days to maintain the 1/3 rule. If the lawn is fertilized with synthetic fertilizer during the already natural growth flush, adjust the mowing frequency as needed. A better fertilizer timing would be to allow the natural flush to slow down and then apply it. Lawns being fertilized organically will not see that extra amount of rapid growth and have a sustained spring greening. A key part of the increased mowing strategy is to be sure your mower blade is sharp. It should be sharp not only start the season, but kept sharp all season long. Your lawn will look better, and the mower will not work as hard, reducing the hydrocarbons in the environment.

Crabgrass is opportunistic; all that is needed is a bit of open space in the lawn to get started. Additional cultural practices can include topdressing and reseeding if the open spaces are more than about 4 inches across. Existing grass plants can usually fill in smaller areas during the growing season.

To help promote your lawn grasses over crabgrass and other weeds, encourage deep roots. Without any outside influences, soils do compact over time, so providing a core aeration will easily promote better water infiltration, soil air into the profile and encourage those deeper grass roots.

If you can promote a better lawn this season, crabgrass seeds will not have the same opportunities to germinate in 2019.

Finally Time to Garden! https://web.extension.illinois.edu/dkk/eb192/entry_13343/ Mon, 30 Apr 2018 13:16:00 +0000 https://web.extension.illinois.edu/dkk/eb192/entry_13343/ That magical average frost-free date of May 5 for our area is quickly approaching. Given the weather patterns we have been having, sticking to the May 5 date may not be a bad idea this year. We read about that average frost-free date where there is still a 50/50 chance of a frost and then that "absolute" frost-free date that is about two weeks later. Longtime gardeners have learned just how much they can push that average frost-free date in their landscape and vegetable garden. Conditions like the sun/shade pattern, soil types and any microclimates influence when we can begin gardening.

Garden centers have based when their woody plants, flowers and vegetables will be ready for sale based on our long-standing air and soil temperatures over many years. Right now, they are all available and ready for purchase, but that does not mean it is safe to plant all of them now in our exposed yards. Nightly, garden centers protect any of the stock that have tender foliage and expanding flower buds. Shrubs and perennials that overwintered locally and are still dormant can be planted without worry. Shrubs and perennials stocked from warmer climates can be planted knowing cold weather protection may be in order or you may hold them in a warmer location to be planted later. The same guidelines apply for the majority of perennials; still dormant, go for it. Early spring growing pansies are a common example of a flower that prefers cooler temperatures.

You can find cold and warm weather vegetable transplants now too. Those cold and cool weather transplants like cabbage, kale, and lettuces benefit from our current air and soil temperatures. Warmer season transplants, like those of tomatoes and peppers, are considered tender vegetables and do not like cooler or cold air and soil temperatures. The really warm season vegetables include our vine crops like cucumbers, watermelon, summer and winter squashes. If you were able to challenge the weather and get in the vegetable garden then potato seed pieces and a sowing of peas and lettuce has already happened.

The more you read about those very hardy, frost-tolerant, warm season and warm-loving vegetables and their planting dates, the more you will see words like "may be planted" or "may be sown up to xx days before the average freeze or frost dates." This lets us know planting and sowing dates are a bit of moving target every year. Another bit of helpful information will be how many growing days we have in a season. In northern Illinois, a good number to go with is 160 days. Compare that with the very southern part of Illinois where gardeners will have an extra 40 or so days to grow their garden vegetables.

Keep your gardening fingers crossed that our nights get slowly warmer and our daytime temperatures rise as well and plant when you can.

Spring is Coming https://web.extension.illinois.edu/dkk/eb192/entry_13336/ Wed, 25 Apr 2018 08:06:00 +0000 https://web.extension.illinois.edu/dkk/eb192/entry_13336/ There are signs, despite the weather pattern, that spring will indeed arrive this year.

More and more spring bulbs are showing up with flower stalks well above the soil line waiting for a bit better weather to bloom. There is even an up-side to our temperatures. If it remains cooler, those spring blooms will last longer in the home landscape once they open.

Red and silver maples have been shedding the bud scales. There is clearly a red coloration appearing from the emerging tiny flowers. The change of silver maples is not as bright, more of a light green, yet clearly those flower buds have been swelling.

Cornelian Cherry Dogwood can be seed in neighborhoods about to give us a yellow bloom show and later that great shiny red berry. It has been spotty, but Forsythia have begun to bloom in the more protected areas. We did not have winter temperatures that would have damaged or killed the buds. There are many different varieties of Forsythia, so if you have one in the landscape and there is no bloom show yet, just hang on.

Despite the weather, signs of life are there in the perennial beds too. You can begin to see the crowns of your favorite plants, but also not-so-favorite plants, like perennial broadleaved weeds and grasses. Rosettes of dandelions are there, as is quackgrass.

While we wait for other spring flowering shrubs to show signs of life, it is a great time to look at them and do any pruning to remove any already-dead stems. Right now, the best example in many landscapes would be red twig dogwood. There is very likely some dead branches to remove. Good tissue has that nice red color, while the bad branches are a light to dark tan, eventually turning black. By removing the dead wood at the crown, you will be encouraging new shoots from there as well.

Soil temperatures have remained cold, so lawns may have not come alive yet. We have seen that brighter green on protected portions where temperatures are warmer. Data from Illinois Climate Network for the area for April 19 revealed just how cold the maximum soil temperatures are:

  • On bare soil, 2 inches below the surface – 36.70 F
  • At 4 inches below the surface on bare ground – 34.20 F
  • Bare ground should be warmer than ground temperatures farther down, yet temperatures at 8 inches below the surface are warmer right now.
While we continue to wait for true spring weather, enjoy walking the yard and looking for those incremental signs that spring is coming, even if it is at glacial speeds this year.