Extraneous grass in the lawn can be a nuisance, especially for visual reasons, as it prevents a nice even green. Control of these unwanted wild grasses is often difficult and time-consuming, but possible.
- thick wild grasses partly strong competition to lawn grasses
- rapid spread in new lawns or patchy lawns
- especially common are millet, annual bluegrass, common bluegrass and couch grass
- manual control is most effective
- Optimize lawn care to prevent foreign grass in the lawn
Control of grass in the lawn
There are several types of grasses that like to establish themselves as alien grass in the lawn. Below we present the four most common ones and give tips on how to get rid of thick wild grass.
Note: You should refrain from using herbicides, because with them you will not only fight wild grasses, but all organisms living in the green area.
Millet, especially blood, hen, bristle and finger millet, is one of the most common thick foreign grasses in lawns. It is an annual, meaning it germinates in the spring and dies in the fall. It is recognized by its broad leaves and culms and numerous spikes with great seed potential. It forms side shoots and large clumps. Millet needs a lot of warmth, which can be used mainly as a preventive measure. However, direct control is more difficult.
If possible, control should be carried out before the millet flowers or forms seeds. The more millet has already spread in the lawn, the more difficult it is to control.
- Manual pricking out is very effective
- as early as possible
- be sure to remove the roots from the soil
- scarify lawn in early summer
- then mow with low set mower
- regular mowing prevents blooming
Tip: Without regular mowing, this weed can reach heights of up to one meter.
The thick, horst-forming, usually 10-15 cm tall annual meadow grass (Poa annua) is easily recognized by its striking white flowers. It is vigorous, continuously producing shoots, flowers and seeds, as well as long creeping roots. Poa annua is also an annual, but its strong seed production ensures renewed growth the next year. In addition, it already blooms in June. With the use of robotic mowers, the wild grass spreads particularly quickly.
Proper care, especially a targeted and well-dosed fertilization in May/June, strengthens the lawn grasses and makes life much more difficult for the foreign grass in the lawn. Otherwise, manual removal is also recommended:
- set up with a rake and mow down
- easily cut out flat roots by hand
- prick and pull out around a horst
- soil should be dry
- reseed the resulting gaps
- water rarely, but thoroughly
- scarify in spring, mow regularly
- only mow with a catcher bag
Tip: Annual bluegrass loves moist soil because it dries out relatively quickly. This makes the right watering strategy all the more important, ideally with longer sprinkling intervals.
Common bluegrass (Poa trivialis) is a shallow-rooting alien grass in the lawn and grows very early before all other grasses. It also prefers moist locations. It is conspicuous in spring by its light green, broad, extremely thick leaves and reddish stems. In prolonged drought, it turns reddish and dies. Control of common couch grass in lawns is much the same as that of annual bluegrass.
Common couch grass
Common couch grass (Elymus repens) is very adaptable and grows even at low temperatures. It can be recognized by its 6-30 cm long and 3-5 cm, rarely up to 10 cm wide and limp, blue frosted leaves. From June to August, long loose, two-rowed spikes appear. Unlike the grasses mentioned above, couch grass grows perennially. It spreads by seeds and strongly branched underground stolons, with new culms forming from each node of the rhizome. All this makes it a dreaded foreign grass in the lawn, which you need to remove completely with its roots.
- cut out with sharp knife or spade
- Sieve the soil if necessary
- Cover the area with dark foil for at least one gardening season (6-12 months).
- weigh down the edges of the foil with stones or the like
- subsequent replanting of lawn required
- alternatively displace couch grass by overseeding
- for this purpose over-seed the gaps with abundant lawn seed
- then water twice a day
- Apply nitrogen fertilizer every two weeks from spring to fall.
Tip: Common couch grass seeds can germinate in the soil for up to ten years. It is therefore all the more important to remove them early and, if possible, before flowering.
Frequently asked questions
What causes unwanted think grass in the lawn?
Most often, lack of or insufficient care of the lawn is responsible for the increased occurrence of wild grasses. Not infrequently, they are introduced with the lawn seed or the seeds are spread by birds. They can spread especially easily in less dense and patchy lawns.
Could millet be tolerated in a utility lawn?
A certain number of these wild grasses is quite tolerable, provided that you do not attach importance to a spotless ornamental lawn and they do not get out of hand. In any case, it is impossible to prevent them from growing over completely. In addition, the seeds serve as a food source for many small animals.
Is it advisable to simply bury the couch grass?
Especially in the case of couch grass, undermining is not recommended, because every little piece of root that remains in the soil would contribute to the spread of this stubborn grass and exacerbate the problem. It would therefore be counterproductive.
When does it make sense to replant the lawn?
A new planting is usually useful when foreign grasses have already spread very strongly in the lawn. If you were to remove them all, there would probably not be much left of the actual lawn. In this case, it is better to replant the lawn and remove all the grasses and roots from the entire area beforehand.