Not always what the hobby gardener wants grows in the home garden. Instead, uninvited, mostly annoying, sometimes actually disturbing plants keep growing between the hoped-for vegetables. It is often not easy to get rid of these plants, which are generally decried as “weeds”. Here we reveal how biological methods can be used to combat one of the most common weeds - the thistle - permanently.
Unpopular species of thistle
It should be mentioned in advance that not every thistle in the garden is useless. Because even if the weed thistle is mentioned in general here, the hobby gardener usually does not have the diversity of the thistle family in mind. In contrast to the ornamental globe thistles and their relatives, which are particularly useful for insects, they are stubborn and undesirable Creeping thistles, and a small group of closely related species. The proposed measures to naturally destroy thistles and drive them out of the garden therefore only relate to the well-known and unpopular creeping thistles. Before taking any measures, it is therefore worth taking a closer look at what is actually growing there. Otherwise, guests who are both useful and nice to look at will quickly be eliminated.
Combat scratching thistle
Two paths to the goal - approaches to weed control
In order to effectively destroy a weed, there are two basic approaches to proceeding:
1. Killing and removing existing plants
2. Preventing weeds from multiplying and spreading in the garden
Of course, both approaches cannot be strictly separated from each other and, due to the close connection, usually lead to the goal in combination. Nevertheless, there are different focal points that can lead to different solutions.
prevent proliferation
How do thistles reproduce?
In order to recognize which type of control will lead to success with thistles, one should first know how they reproduce. Because the permanent expulsion and thus the basis for not having to fight the annoying plants again and again will only succeed if, in addition to eliminating the existing plants, the formation of new shoots is also prevented.
It is precisely here, however, that the thistle is a special herb. Because it has different mechanisms of propagation and distribution:
1. Propagation via seeds
The thistles form flowers in a plant-typical way, which produce seeds after pollination. The seeds fall out after maturity and, in conjunction with acceptable growth conditions and a viable environment, lead to daughter plants.
2. Propagation via the rhizome
From a biological point of view, the thistle can be counted among a group of special plants that, in addition to propagating via seeds, also reproduce via the rhizome, i.e. the root. New buds keep emerging from the spreading root, which sprout upwards and produce new thistles after breaking through the topsoil. Even after removing the above-ground parts of the plant, new plants emerge from the nutrient storage rhizome. Even pieces of root can produce new shoots.
danger: The rhizomes of the thistle plants are considered to be extremely persistent and can persist in the soil for a long time. A temporary absence of new plants is not immediately to be equated with a suppressed reproduction of weeds.
Methods for combating the thistles
From the knowledge about the propagation methods of the thistle, in connection with the already mentioned, basic approaches to weed control, there are different ways to get the stubborn plants under control. These home remedies have proven effective and sustainable over time:
Mechanical removal
- Pull out thistle plants complete with their roots, or prick them out with a root cutter
- Advantage: the plant is removed immediately, including any seeds that may be present, and the root is also removed from the soil
- Disadvantage: high probability that pieces of root remain in the ground and later produce new shoots
tip: After rain or artificial irrigation, the root's grip on the wet soil is reduced, so the likelihood of removing the entire root is higher.
Even mixed weed killers
- Water the plant and especially the root area with a mixture of 2 parts vinegar and 1 part salt
- The plant dries up completely due to the changed osmotic pressure in the cells
- Advantage: With sufficient use, the root also dries out completely, so the plant is completely and permanently removed
- Disadvantage: lengthy procedure, application shortly before seed maturity no longer makes sense, since seeds fall out before they dry up and produce new plants, intensive application leads to acidification and salinization of the soil
mowing
- Mow thistles after rain or intensive watering, water penetrating the hollow stems quickly leads to rot, which spreads to the root
- Advantage: the plant dies including the roots, further propagation stops
- Disadvantage: quite unsafe method, since rot does not necessarily occur, not very suitable for individual plants in the garden bed
tip: No matter which method is chosen, the first attempt usually does not immediately lead to the permanent absence of the annoying plants. A persistent and consistent approach helps here. With each new removal, the plant is weakened, so that new shoots are already weaker. In the long run, the thistle will therefore run out of strength and a new appearance will not occur. However, if the efforts are temporarily interrupted, the success can quickly be lost completely, since a single maturation phase of the seeds is enough to start the fight all over again with new plants.
deprivation of livelihood
If you look at the topic of thistle destruction, you repeatedly come across the suggestion of depriving the thistles of their livelihood by changing the soil conditions. Agricultural engineers and biologists in particular are constantly discussing this possibility. In fact, the thistle loves certain soils and has a hard time growing on other soils. In the context of intensive soil use, a change can be brought about in the long term through crop rotation and intercropping, which adversely affects the growth of the thistles and can even lead to their disappearance. On the other hand, these methods can hardly be implemented in the kitchen garden at home, since self-supporters and hobby gardeners love and seek out the variety of local products. Coordinating crop rotation with targeted weed destruction seems understandably unrealistic from these points of view.
