Weeds in Landscape Beds

Jeremy Hebert  |  10/7/2011 12:16:11 AM

With the burst of cool air recently, many people are starting to get their landscape beds ready for the fall. Some of these landscape beds were neglected during the dog days of summer and now that the temperatures are getting more pleasant, this is a great time to do the things that we wanted to do but didn’t get to do.

If the landscape beds were the last thing on your mind this summer, which is very possible, these beds are probably full of weeds and need to be managed this fall. Weeds can cause various problems because not only do they look bad, but also they complete for the same water, same nutrients and the same sunlight that the good plants need. When these weeds and landscape plants are competing for all of the same components that make a good plant, that means that the plants that you want all the water, nutrients and sunlight to go to are not getting the recommended amounts.

There are several different kinds of weeds that we have to worry about: broadleaves, grasses, and sedges. Broadleaves are very common weeds and are the weeds that have netted veination, have two cotyledons, have taproots and sometimes have showy flowers. An example would be clover. Grasses are usually identified by the parallel veins that run through the grass blades, have one cotyledon and a fibrous root systems. An example would be dallisgrass. Sedges, sometimes called nutgrass or cocograss, are one of the most troublesome perennial weeds in landscapes across Louisiana. They can be identified by having triangular stems, have leaves in threes and sometimes have a nut attached to the roots. An example would be purple nutsedge). All three different kinds of weeds pose problems in landscapes if not controlled.

Weeds can be easily spread throughout the landscape beds by nature or by humans. Nature’s way of spreading weeds is not something that can be avoided. Many birds and animals can bring weeds into the landscape and the next thing you know, the seeds have sprouted and the landscape is now infested with weeds. Wind is also another common way that nature can spread weeds. Since the weeds and seeds do not weigh a lot, they can easily be tossed around and find their way into the landscape bed. When the winds are strong enough, weeds can travel far distances and can become a nuisance. Rains and flooding can carry weeds for long distances as well. When a given area receives large amounts of rainfall and the excess water has not soaked into the ground, the risk of flooding occurs. As the flooding occurs, the water runs across areas of land and can easily pick up any weeds and seeds and deposit them as the water recedes.

Humans can easily spread weeds and, most of the time, this can be prevented. Many home owners have their own compost piles and some make their own mulch. Compost and mulch can add valuable nutrients and organic matter to the soil; however, home owners run the risk of adding weeds to their landscapes due to the impurity of their compost and mulch piles. Many compost piles and mulches will include broadleaf, grass and sedge seeds. As the compost piles decompose, the seeds may lie dormant until they reach the landscape beds; this also happens with landscape mulches. If homeowners are using their own compost and mulches, it is important that the homeowner tries to add material to the piles that will decompose, benefit the landscape and not increase the risk of weeds.

Proper mowing by humans can also reduce the risk of weeds. Even though mowing is not a chore that we enjoy all doing, mowing properly can greatly affect whether or not your landscape has weeds. When mowing, be sure and have the grass clippings blowing away from the landscape beds; this will allow any seeds or any grass with roots to be directed away from the landscape. If the grass is blown in the bed, chances are some seeds and grasses with roots probably found its way in the landscape beds. If this happena, the roots may establish themselves in the landscape and seeds may germinate.

As homeowners examine their landscapes periodically, proper weed control can be in motion. Be sure that when pulling weeds in your landscape beds, you are pulling the whole weed and roots out of the ground. If the roots are not pulled out of the ground properly and just the top part of the weed is pulled, the weed was just pruned and more than likely, the weed will come back. Once the weeds are pulled, it is important to properly discard the weeds and not just throw the weeds into the lawn because if the weeds are thrown in the lawn, you are now increasing the risk of the lawn being infested with weeds.

Proper lawn and landscape cultural practices are the number one line of defense when reducing the risk of weeds in landscapes, but sometimes weeds still pop up. Even with proper cultural practices, weed control is sometimes needed with herbicides. There are many different herbicides that can be used, but be sure that when using the herbicides, you know exactly what is being used. Since there are many different herbicides and different herbicides target different weeds, proper identification of the weed is a must. Knowing the difference between a broadleaf, grass, and sedge can benefit homeowners in the proper control of weeds. If a herbicide is needed, homeowners need to be sure and read the label and know what the proper rate and safety precautions are for that particular herbicide. Before applying the herbicide, make sure the sprayer or spreader is properly calibrated for the rate that is needed. When applying herbicides, make sure to apply it in a safe manner and do not get too close to landscape plants. If the herbicide gets too close to landscape plants, landscapers run the risk of damaging or killing the landscape plant that was just sprayed with herbicide.

Mulching is also a very good weed preventer in landscapes. Since some landscape beds were neglected this summer, homeowners may need to reassess the landscape to see if another application of mulch is needed. The two most popular mulches that are used for landscapes are pine and cypress mulches. Both of these mulches act as great barriers for weeds by not allowing sunlight to hit the soil and also acting as a barrier from the outside elements. If reapplying mulch to landscape beds, applying mulch 2”-3” thick will give the most benefit. Not only is the mulch acting as a weed preventer, but also keeping much needed moisture in the landscape bed and it also helps to beautify the landscape.

By properly managing your landscape in the fall months, homeowners can have their landscapes basically weed free. This does take time and effort from the homeowner, but the benefits can be rewarding. If the landscape was infested with weeds this summer and if the proper chores are done this fall, you can turn your ugly landscape that was infested by weeds, into a burst of excitement by simply weeding the landscape beds and re-mulching.
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