Couch grass, also known as hairy barley, string grass or creeping couch grass, are perennial herbaceous root weeds from the grass family. Some species develop long, underground rhizomes that have the ability to root at each individual node. New plants can even develop from small root residues. It is therefore particularly important when fighting couch grass in the lawn to completely remove all root residues from the soil. Elymus repens form erect, bare or drooping culms and can grow up to 120 cm tall depending on the species. It is spread by runners, which this plant forms in large numbers.
Table of Contents
- Scientific name: Elymus repens
- Belongs to the grass family of plants
- Depending on the species, it can reach heights of between 40 and 120 cm
- Use as a medicinal herb
- Wheatgrass is shallow rooted
- It forms long underground rhizomes
- Strong runners
- Extraordinarily multiplies
- Blooms from June to September
- Grows on fallow land, in gardens and fields
- Mechanical combat
If couch grass occurs sporadically, weeding out with a sharp knife or a special weed puller is often recommended. It is best to start before the couch grass flowers or forms seeds, because it not only spreads via stolons, but also reproduces via seeds. When cutting out, you should always try to remove as much of the root system as possible, preferably the entire root. However, this stubborn plant cannot be completely removed by cutting it out. As a rule, isolated root residues always remain in the soil, from which new plants develop again. Even the smallest root remains are sufficient for this.
Digging not recommended
Removing the couch grass by digging it up or digging it up is only recommended to a limited extent or not at all. On the one hand, the roots are literally dismembered and the spread is supported rather than prevented. In addition, the lawn does not really look any better afterwards.
If you still want to try it, it is better to use a shovel instead of a spade and follow the course of the root to finally remove it. You should be very careful when doing this, as the roots tear off relatively easily and can then hardly be found. Here, too, root parts always remain in the soil, which are then easily able to form new runners and promote further spread of this weed.
Lay out plastic foil
- Many hobby gardeners have had good success with opaque film.
- This method of combating is quite lengthy.
- After this treatment, the lawn must be replanted.
- A simultaneous death of lawn grasses cannot be avoided.
- The area in question is completely covered with dark foil.
- The edges are weighed down with stones, wooden beams or the like.
- Neither rain nor sunlight should penetrate to the ground afterwards.
- The film stays in place for at least one gardening season.
- It is better to leave them for 6-12 months, the longer the better.
- In the best case, the entire couch grass dies off.
- After this time, remove the film again
- Then work the surface thoroughly with a cultivator.
- Carefully remove all dead plant remains.
- Then sow again
Control with chemical agents
Total herbicide Renofluid Royal
If conventional means have not been successful, the only option is usually to replant the lawn, for example with the help of the herbicide Renofluid Royal. This method is often the safest and most promising when there is very heavy weed growth in the lawn.
First you have to remove the old turf, about three weeks before you can start reseeding. During these three weeks, the lawn is no longer cut. A few hours before applying this herbicide, preferably in warm weather, the area should be watered. The herbicide is then applied according to the manufacturer’s instructions.
After about 1-3 weeks, depending on the temperature and weather, both the grass and the couch grass and other lawn weeds are brown, ie they have died. Now comes the most important part, the thatch must be thoroughly removed. To do this, the area must be deeply scarified. The lawn thatch is torn open on the surface of the ground and the surface of the ground is loosened. When scarifying, be sure to work crosswise.
After scarifying, the entire lawn thatch is thoroughly removed with a rake or lawn comb, revealing the open soil. Any unevenness can then be corrected with well-washed sand or a mixture of sand and soil. Now you can start sowing again. As already mentioned, you should definitely pay attention to high-quality seed.
Lawn weeds cannot be prevented completely . However, you can do a lot to prevent it, because a healthy and dense lawn is much less susceptible to couch grass and co. Proper care of the lawn plays a decisive role here, because if the care is not right, weeds like couch grass can settle very quickly and spread.
Proper care includes watering the lawn, fertilizing, mowing and scarifying. It is best to water the lawn once a week. You should water thoroughly, about 10 liters per square meter, so that the water can seep at least 15 cm deep into the soil. In contrast to loamy to clayey soils, sandy soils have to be watered more frequently, possibly every two days in summer. You should never water in the blazing midday sun, because that could burn the stalks.
In addition to watering, the lawn must be regularly scarified, once in spring and once in autumn, and then freed from thatch. Mowing is no less important. Mowing should be done for the first time in April in April and then regularly from then on. A stem height of about 4 cm is optimal.
Since lawn grasses also lose nutrients when mowed, fertilizing is another important step in keeping the lawn healthy. You should fertilize about 6-8 weeks after the first cut and then again in summer and one last time in autumn. If not fertilized at all or too little, the lawn gets gaps in which mosses and, above all, weeds such as couch grass or clover can settle.
Remove weeds before sowing the lawn
- Stop the growth of lawn weeds from the outset if possible.
- Thoroughly remove weeds before planting a new lawn.
- Remove couch grass, clover and dandelion in particular as thoroughly as possible.
- Remove weeds before they bloom or form seeds.
- Always remove the entire root.
- Otherwise the couch grass will be back in a few weeks.
Cause of couch grass growth
There can be a variety of reasons why couch grass grows in the lawn. The most common cause is a nutrient deficiency, because lawn grasses have a relatively high nutrient requirement. In the event of a deficiency, the grasses become weaker, more and more gaps form in the lawn, which in turn means that very adaptable weeds such as couch grass gain the upper hand and can spread extremely quickly. The whole thing is intensified when, in addition to nutrients, water is also scarce.
Another reason for the formation and spread of couch grass is poor-quality lawn seed. The seed ‘Berliner Tiergarten’ deserves special mention here, as it has a particularly strong tendency to weed. Such seeds are bred for rapid growth, which is why they mainly contain inexpensive forage grasses. These grasses shoot up very quickly, but do not form a closed turf, as is actually desired for lawns.
frequently asked Questions
What should you pay attention to when using weed killers?
Weed killers are chemical substances that should only be used when all other measures have failed. Before you buy, you should definitely get advice on which product works against which weeds. Weed killers for the lawn are usually designed in such a way that they only work against certain weeds. However, there is no remedy specifically for couch grass. Accordingly, only total herbicides such as Renofluid Royal come into question here. However, these do not distinguish between weeds and cultivated plants, so they should be used selectively. When using such agents, one should always strictly follow the manufacturer’s specifications. It is important, among other things, that they must not be deployed near water.
Can you prevent root weeds like couch grass?
The best way to prevent the formation of root weeds is to properly care for the lawn, i.e. fertilize, mow, water and scarify. Otherwise, it is helpful to thoroughly remove all weeds from the soil before laying a lawn. In order to permanently ban couch grass from the lawn, their reproduction should be prevented. Because they reproduce by both seed and underground stolons, which can grow a meter or so in any direction over the course of a year, it’s important to consistently remove couch grass before flowering without leaving root fragments in the soil. However, this is very difficult.