How to quickly recognize the disease and treat the boxwood fungus, as well as information about sprays and whether home remedies can help.
The boxwood owners among us have actually not had it easy for several years. The invasive box tree moth devours entire stands of box trees if action is not taken in good time. Since 2004, however, a completely different type of malware has been causing major problems. The dieback of the Buxus genus, triggered by the harmful fungus Cylindrocladium buxicola, is causing major problems in northern Germany, but also increasingly in the south. Since the boxwood can also be attacked by other fungi, it is important to recognize the symptoms exactly.
contents
- Identify boxwood fungus
- Boxwood fungus: A profile
- Prevent boxwood fungus
- Combat boxwood disease
Identify boxwood fungus
The first signs of infection with C buxicola are leaf discolorations or leaf wilt. Young leaves turn orange-brown and old leaves only get brown spots. Depending on the severity of the infestation, the leaf spots can grow quickly and entire shoots are quickly infected. However, the leaf spots themselves are not a reliable identifier. Only when you also see small black stripes on the affected shoots, which extend from below spread towards the tip of the shoot, you can be sure that it is dieback acts. As the disease progresses, severe leaf fall usually occurs, combined with the death of entire shoots and, in the worst case, the entire box tree dies.
Boxwood fungus: A profile
The pest presented here does not need open wounds to overwhelm the boxwood. If the leaves of the Buxus are wet for at least 5 hours, the fungus can grow into the healthy leaf tissue and the infection can no longer be stopped. If the fungus finds good growth conditions (25 °C), the characteristic symptoms can already be seen a week after the first infestation. However, if the temperatures are permanently well above 25 °C, then this is not good for the fungus. A hot summer can therefore significantly limit the infestation. In addition, the fungus forms C buxicola so-called permanent spores. These can survive in the soil for at least 4 years and reinfect beech trees. The fungal spores are spread by wind, water splashes and, of course, through trade and infected clippings.
Prevent boxwood fungus
All measures to prevent the boxwood fungus should be fully exhausted, since the dieback is very difficult to combat. First of all, you should try to keep your box trees above ground as dry as possible. Because if the leaves dry off quickly, the fungus has less time to germinate and thus infect the plant. So look for a sunny and airy location for your box trees - the leaves can dry faster there. In addition, the boxwood likes an even water supply. When watering, make sure that only the soil gets wet and not the leaves.
The choice of variety can also help to avoid shoot death. In general, vigorous boxwood varieties are said to be less susceptible, including, for example, the “Herrenhausen”, “Faulkner” and “Brno” varieties. Unfortunately, there are still no completely resistant varieties. In the case of box trees that are already infested, a radical pruning back into the healthy wood can help, but there is no guarantee of success. It is important that the cut shoots do not end up on the compost. Because of the problematic permanent spores, all cutting waste belongs in the residual waste. It is also advisable to remove the top layer of soil under a diseased Buxus. There the earth is enriched with falling permanent spores. Despite these measures, it is not necessarily recommended to plant a new box tree directly on the spot where an infected box tree previously stood.
Combat boxwood disease
As previously mentioned, combating boxwood disease effectively is very difficult. The harmful fungus can no longer be combated once it has penetrated the boxwood. An additional problem is the enormous resilience of the fungus. So far we have not been able to find any reliable information that confirms that home remedies or organic sprays are successful against the fungus. So it is not possible C buxicola treated with natural or biological preparations.
Even the chemical club only works with a preventive spray. In practice, this would mean that you would have to spray your box trees with fungicides as a preventative measure after every rain in the gardening season. Ultimately, everyone has to decide for themselves whether this is the right way for the hobby gardener. In the case of box trees that are already heavily infested, the only thing that often helps is to clear the diseased plants completely, even if there are no replacement plants with a similar appearance. It is to be hoped that breeders will quickly develop resistant varieties or find new methods of combating the harmful fungus.
Algae against boxwood disease
For some time now, more and more of our readers have been reporting on the successful fight against boxwood disease or boxwood disease. of the fungus through algae lime. If you spray the box plants between the end of April and the beginning of May algae lime, the plant shows a clear recovery within a few months. The treatment should also be used against the box tree moth and its eggs algae lime help.
Boxwood fungus is not the only problem boxwood owners face. Also the annoying one box tree moth is probably familiar to most hobby gardeners. We will introduce you to the pest and explain how you can combat it.