Laying a lawn is sometimes quite laborious and time-consuming. So it is annoying when, after a while, tufts of light green grass stand out on the “Premium Top Quality Family & Fun” lawn. The culprits are annual bluegrass (Poa annua) or common bluegrass (Poa trivialis).
They even make life difficult for sod producers. This is because these grasses sometimes flower shortly after emergence and form many, many seeds. The fatal thing is that if you cut meadowgrass before it flowers in order to suppress it, it forms more runners.
Even if the botanical name is not familiar to every amateur gardener – annual bluegrass is very present and also relatively easy to recognize:
it has a light shade of green, it is a cluster-forming plant and roots rather shallowly, it has short, creeping shoots and it often comes to flower
Common bluegrass is sometimes used to establish lawns, as it grows well in moist and shady locations. However, its light coloration also makes it stand out from other grasses. With long creeping shoots, it likes to conquer gaps in the lawn and yellows quickly, which also detracts from the look of the lawn. Its flowering period ranges from June to July.
Containing the unwanted panicle grasses
A panicle grass can soon infiltrate the entire lawn. So here it means not to remain idle when you discover the bright green patches in the lawn.
Use a special weed pruner to cut them out as deeply as possible. Immediately close the resulting gaps by reseeding. At the same time, apply a nitrogen-rich lawn fertilizer to strengthen the original lawn species such as ryegrass, tall fescue or red fescue.
Proper watering of the lawn is also crucial. This is because the two panicle grasses love permanent soil moisture. Sprinkle the lawn thoroughly, but less frequently. This will also benefit the roots of the desired lawn grasses.
Mow regularly, so that the seed formation of the troublemakers is prevented (despite the stolon formation)!
Unfortunately, lawn herbicides can’t do anything because they only work against dicotyledonous weeds. A total herbicide would certainly help. But then not only the meadow grass would be gone, but the whole lawn.
If you need to do it quickly, there is another trick: simply make the meadowgrass invisible with a fertilizer containing iron and magnesium. This “dyes” it dark green so that it matches the color of the other lawn grasses.