Help the development of the site, sharing the article with friends!
Even if the soil is optimally prepared, there will always be unwanted, but also useful flowering foreign grasses in the lawn. Usually this cannot be prevented. What to do when the lawn is blooming?
In a nutshell
- increased occurrence is often due to incorrect or insufficient lawn care
- Difficult to control in most cases
- It is difficult to stop the spread of these unwanted grasses
- In most cases, removal is only possible manually
Undesirable flowering foreign grasses
Blood-red finger millet (Digitaria sanguinalis)
Source: AnRo0002, 20140827 Digitaria sanguinalis2, Edited by Plantopedia, CC0 1.0
- about 50 cm high sweet grass
- initially recumbent, later kinking ascending, loosely hairy
- considered a host for migratory root nematodes
- Leaf blades finely silky, whitish-reddish central vein
- Lawn blooms in summer and early fall
- three to seven loose false spikes
- First fertilize the lawn heavily
- and/or scarify shallowly in early summer
- Millet stands up, mow with a deep cut
- regular fertilization and overseeding, keep the lawn tight
- or cut out before flowering
Annual meadow grass (Poa Annua)
Source: AnRo0002, 20141123Poa annua1, Edited by Plantopedia, CC0 1.0
- inconspicuous, low, light green-yellowish grass
- populates bare spots and gaps almost overnight
- occurs from April to June
- light green stalks with paniculate, almost white flowers
- seldom longer than two inches
- Spikelets green, rarely tinged with violet
- when the lawn is in bloom, fertilize in May and June
- water abundantly less frequently
- Combat by manual stabbing
- only mow with a grass catcher
- Robotic lawnmowers promote the spread of these grasses
Tip: The panicles of flowers and seeds form throughout the summer if the weather is favourable. Incidentally, the annual meadow grass is considered a good nitrogen indicator.
Common panicle (Poa trivialis)
- grows before all other grasses in spring
- easily confused with millet
- prefers damp and wet soils
- takes root only superficially
- Lawn flowers from June to July
- light green leaves in spring
- later reddish stem base visible
- the older the more shaggy the growth
- turns reddish-brown when dry and dies
- leaves unsightly bald spots
- Control is similar to that of annual bluegrass
Green foxtail (Setaria viridis)
- flowering grasses with growth heights of 5 to 50 cm
- buckling ascending culms
- very thin, not hairy
- Leaves are green with a light or purple central vein
- Lawns bloom from summer to early fall
- Flower spikes smooth when brushed over
- compact, uninterrupted
- Bristles thin, long, soft, green, later turning violet
Notice: Millet is found above all in patchy lawns and newly seeded areas, as well as at soil temperatures of 20 degrees and above. At temperatures below 15 degrees and less than 12 hours of light, it dies.
Bermuda Grass (Cynodon dactylon)
- perennial flowering grasses, about 30 cm high
- branched rhizome up to a meter long
- often forms dense lawns
- Culms slender, lying, with adventitious roots and side shoots
- strong competitor for water
- flowers from summer to autumn in lawns, in warm areas all year round
- up to seven finger-like spikes
- hard to get off the lawn
Notice: Control is only possible selectively by hand or over a large area using a total herbicide (the use of which we expressly reject here).
Barnyardgrass (Echinochloa crus-galli)
- flowering grasses up to 80 cm high
- buckling upright or ascending culms
- hairy at the nodes
- Leaves dark, grey-green, relatively wide
- Median vein whitish, youngest leaf rolled
- Lawn flowers from July to September
- Inflorescence, compound panicle
- Spike-like partial inflorescences, tinged with light green or violet
couch grass (Elymus)
Source: Stefan.lefnaer, Elymus repens sl5, Edited by Plantopedia, CC BY-SA 4.0
- grows faster than grasses from turf mixes
- persistent, far-reaching subterranean runners
- Leaves deep green, shimmering bluish
- tall shoots, growing in different directions, 50 to 120 cm high
- Flowering from June to August
- slender, spiked inflorescences, 5 to 20 cm long
- Difficult to get rid of
- Pinch out regrowing plants as soon as they emerge
- preferably with a complete root
Bent Grass (Agrostis stolonifera)
Source: Matt Lavin from Bozeman, Montana, USA, Agrostis stolonifera (3821003330), Edited by Plantopedia, CC BY-SA 2.0
- evergreen, persistent, 8 to 40 cm high
- forms a dense and soft carpet in the lawn
- leafy aerial runners
- Leaves glabrous, finely pointed, gray to blue-green
- smooth, glabrous, branching culms, two to five nodes
- on lower nodes, shoots and shoot-borne roots
- blooms in lawns between July and August
- elongated paniculate inflorescences
- Spikelets in dense clusters
notice: Although Bent Grass is beautiful to look at, it is not particularly hard-wearing or shear-resistant. Frequent scarifying also encourages growth.
Desirable flowering lawn grasses
Perennial Ryegrass (Lolium perenne)
- very popular in lawn seed mixtures
- Sturdy, hard-wearing, lush green flowering grasses
- fast-growing, clump-forming, around 20 cm high
- grow particularly well in nitrogen-rich soils
- Lawn flowers from May to autumn
- Flower culms approx. 70 cm high
- the colder, the more vulnerable
- Regular mowing stimulates growth
Attention: Perennial ryegrass is one of the most common pathogens for hay fever in this country.
Red fescue (Festuca rubra)
- often contained in high-quality lawn mixtures
- perennial, forming runners or clumps, undemanding
- Growth heights between 20 and 80 cm
- steep upright culms
- Leaf-sheaths almost completely closed
- blooms in lawns from April to October
- upright, sparsely branched panicles
- Conditions may vary by subspecies
frequently asked Questions
Why do flowering grasses spread in the lawn?Undesirable grasses can settle and spread more easily the more careless you are with lawn care. If the lawn becomes patchy, they can spread very easily. A dense, closed turf is all the more important. Often some of these flowering grasses are also included in lawn seed mixtures.
When is the best time for appropriate overseeding?Reseeding can usually be carried out during the entire vegetation period. If the lawn needs to be completely re-laid due to excessive growth of foreign grass, spring or early autumn is the best time to do so.
Is it possible to avoid flowering grasses in the lawn?It is not possible to prevent these grasses from settling completely. Nevertheless, you can counteract uncontrolled spread with the right lawn care. This includes, in particular, targeted irrigation and long dry periods, as well as correct fertilizer application and regular, at best weekly mowing. In some cases, superficial scarifying can also render seeds harmless that are already beginning to germinate in the soil.