If you let weeds grow in your lawn, you’ll soon be at a disadvantage. Dandelion, sorrel and the like are crowding out the green carpet in a short space of time. Only a consistent approach can still save the lawn. To do this, however, you must know which weeds you are dealing with. Annual species are controlled differently than biennial species. Find out below which important weeds there are and how to identify them successfully. The method by which the unmasked weeds in the lawn are combated is almost a matter of course.
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Difference: annual and biennial weeds
Between 600 and 1,000 species of plants are considered weeds by definition. Essential determinants are an invasive or disruptive character that impairs the growth of ornamental and useful plants. More than half of all weeds come from the plant families of the cruciferous, sweet grass, daisy family and carnation family. The most important basic information for successfully controlling weeds in the lawn is whether they belong to the annual or biennial species.
Annual weeds grow as seed weeds for one season, which will germinate, flower and produce countless seeds within a year. Dandelion and chickweed are well-known representatives of these short-lived plants. If the seeds get into the soil through deep tillage, they can survive for many years. Especially when laying out a new lawn, there is a high risk of seeds nesting under the sod.
Biennial weeds retreat to the rootstock in winter, only to reappear the following spring. They reproduce mainly by underground runners. The universally dreaded field horsetail is one of them, as are various sorrel species. Hardly anyone can get at these plants with weeding; on the contrary, a wrong mechanical approach can still contribute to the further spread of these lawn weeds. Numerous weeds do not just live for two years, but spread in the garden over many years if they are not consistently stopped.
Identify and control annual weeds
Dandelion (Taraxacum officinale)
- Trivialbezeichnung: Pusteblume
- Growth height 10 cm to 30 cm
- Yellow flowers and the unmistakable white paragliders
Although dandelion is a seed weed, the plant has a deep-reaching taproot that makes eradication much more difficult. In order to permanently remove the troublemaker from the lawn, special weed extractors that capture all parts of the plant are suitable. This measure should be taken in good time before flowering, before dandelion lives up to its name as a dandelion and diligently distributes the seeds in the lawn. If the infestation has already got the upper hand, the last resort is to use a herbicide such as Bayer’s Universal Lawn Weed Free.
Gooseberry (Bellis perennis)
- Capate white flowers with yellow tubular florets in the centre
- Flowering time from March to November
- Growth height 5 cm to 15 cm
Not every hobby gardener finds it easy to fight the pretty little flowers in the lawn. If they are allowed to reproduce unhindered on the grass surface, sooner or later they will crowd out the less competitive blades of grass. Regular lawn mowing at least prevents seeding.
Medium plantain (Plantago media)
- Pink or white flowers, cylindric on leafless stems
- Basal leaf rosettes with broad, oval leaves
- Growth height 15 cm to 50 cm
The plantain clings to the ground with its deep taproot. Since the leaves and seeds are close to the ground, they are difficult to grasp with your hand. As with many other types of weed, a weed puller provides valuable services in combating it. Since the flower appears quite inconspicuous, plantain is not easy to identify and is easily overlooked.
Weißklee (Trifolium repens)
- Globular white or pink flowers from May to September
- Typical three-leaf clover
- Long taproot without stolons
White clover is representative of all the clover species that infest your lawn because it is by far the most common. Lawn weeds usually signal a lack of nutrients, especially nitrogen. An improved supply of fertilizer strengthens the lawn so that clover in any form is quickly pushed out again.
Millet / Barngrass (Echinochloa)
- Inconspicuous spike flowers from July
- Stiff, upright blades of grass
- Partial inflorescences hang down in an arch
Millet is a fast-germinating sweet grass that quickly overgrows lawns . When temperatures rise, growth begins and flowering begins. The most effective way to combat millet is in the initial phase from June to July. Regular mowing and targeted fertilizing keep millet in check.
Thread speedwell (Veronica filiformis)
- Prostrate stems with sky blue flowers
- Round, small leaves up to 15 mm
- Flowering time from March to June
Not only thread speedwell, but a whole range of other speedwell species take over the lawn during the summer. They are basically easy to identify based on the bright blue flowers. Until then, however, you should not let it come, so that no seeds can be distributed. Weekly lawn mowing is considered the most effective way to combat it.
Vogelmiere (Stellasia media)
- Creeping stems over the lawn
- White star blossoms throughout spring and summer
- Will sprout again in mild winters
Persistent weeding proves to be an efficient countermeasure. However, you should not wait until flowering to prevent propagation by seed.
Identify and eliminate biennial weeds
Kriechender Günsel (Ajuga reptans)
- Blue flowers on stalks 10 to 30 cm high
- Flowering time from April to June
- Downy rosette petals, fading into reddish
In order to get rid of this stubborn lawn weed, the plant should be dug out together with the shallow root system. The resulting bare spots are resown immediately so that the garden bugle does not have a new target to attack. If all efforts fail, only a universal herbicide for lawns can help.
Creeping Buttercup (Ranunculus repens)
- Golden yellow flowers in five parts from May to September
- Green, stalked, pinnate leaves with a prominent central section
Thanks to the bright flowers, this weed species is easy to identify. Immediately after a rain shower, a creeping buttercup can be quickly removed with the weed picker. Even if the weeds mainly spread through rhizomes, flowering and subsequent seeding should be prevented.
Lesser prunella (Prunella vulgaris)
- Forms stolons above ground for propagation
- Small, erect stems, slightly hairy
- Blue-violet to whitish flowers on a small roller
From June to October, the small prunella can be recognized by the numerous small flowers. If the infestation is still manageable, go after the individual plants and prick them out with a sharp knife. Please note the long spurs. As long as even a small piece of root remains in the lawn, the common prunus will sprout again.
Moss in the lawn – difficult to fight
If a dense, green cushion spreads out on the lawn with the typical sparsely leafed mini stems, moss enters the stage of the lawn weeds. Identification is easy even for beginners, although there are hundreds of moss species. Scattered wrinkled moss (Rhytidiadelphus squarrosus) has the dubious reputation of being the most common moss in the lawn carpet. The weeds do not flower, but spread by means of spores. From a distance, it can hardly be distinguished from the green blades of grass. In order to combat moss in the lawn, the cause must first be investigated. If the following grievances prevail in the garden, moss withdraws immediately after they have been rectified:
- Shady location, for example under trees and bushes
- Waterlogged, heavy and compacted soil
- Lawn cut too low or mowed too seldom
- Nutrient deficiencies due to inappropriate fertilization
It is therefore a matter of maintenance aspects that open the door to moss spreading in the lawn. Effective control implies the following procedures:
- Consistent pruning of the trees in question
- Repeatedly apply a thin layer of building sand and lime regularly
- Never cut the lawn shorter than 4 cm
- Apply lawn fertilizer with moss destroyer according to the manufacturer’s instructions
Whatever causes moss in the lawn is based on; by scarifying you give the blades of grass enough air so that they can defend themselves at the same time. With the help of a special scarifier you drive slowly along and once across the lawn. The rotating knife roller combs all moss out of the ground. Adjusting the knives to a depth of 1-2 mm is completely sufficient. Then rake up the combed moss and dispose of it in the compost.
Get rid of root weeds in the lawn with herbicides
While annual seed weeds can be successfully combated by weeding them out in good time before flowering and seeding, the situation with root weeds is more tricky. When you were able to successfully identify the species, the weed already has a more or less developed root system in the soil developed. If you now go to work with the weeder, you can never be sure whether all the biomass has been removed. Root weeds sprout again from even the tiniest remains and the vicious circle closes. Before stubborn weeds in your lawn rob you of the joy of home gardening, using an herbicide as a last resort is worth considering. Modern preparations that are approved for use in the home garden specifically combat weeds, are not dangerous to bees and protect the lawn. The database of the Federal Office of Consumer Protection and Food Safety always publishes all current preparations that are permitted. Some examples:
- Bayer Garden Universal Lawn Weed Free
- Compo Lawn Weed Killer Perfect
- Neudorff weed-free plus
Since excessive weed growth is often associated with a lack of nutrients in the lawn, troubled hobby gardeners decide to use a lawn fertilizer with an integrated weed killer in spring.
- Beckmann premium lawn fertilizer with weed killer
- Compo UV Rasen Floranid
- Dehner weed killer plus lawn fertilizer
- Manna Dur UV weed killer with lawn fertilizer
Although the majority of the preparations give the impression of taking action against all types of weeds in the lawn, the range of effectiveness proves to be selective. You are therefore not spared from successfully identifying the weeds in the lawn in advance in order to then combat them in a targeted manner.
Conclusion
Weeds in the lawn are not only a nuisance, they also pose a serious threat to the hobby gardener’s green calling card. The range of plant species that have been stamped as weeds by definition is long. In the absence of a panacea, the first step is to successfully identify the weed species before deciding on the control method. An essential criterion distinguishes between annual seed weeds and biennial or perennial root weeds. This is followed by the identification, from which the procedure results. The manual or mechanical method is exhausting, but environmentally friendly. The hobby gardener should not be able to avoid using an adequate herbicide against an excessive infestation of root weeds.