As a wild fruit tree, elderberry has a robust constitution, so it is rarely afflicted by diseases. If problems arise, a few triggers come into focus. You can find out what these are here.
umbel wilt
During the ripening period, the umbels begin to wilt from the sides. Faded, red-yellow spots develop on the leaves, while the elderberries ripen at the same time. The course of the disease is promoted by damp weather. Only recently scientists found out that it is a fungal infection. Fusarium sambucinum, a known sac fungus, and Phoma sambuci-nigrae have been identified as triggers.
Effective control agents are not yet available. The extent to which preparations against gray mold and fruit rot have an effect is controversial. All affected parts of the plant should be removed and burned immediately.
drainage
If wet and cold weather prevails during flowering, elderberries are threatened by trickling. The flowers fall off prematurely, resulting in minimal pollination. In addition to unfavorable weather conditions, a lack of nutrients also leads to the disease. How to prevent:
- balanced organic fertilization, without too much nitrogen
- give an additional 10 grams of borax per square meter just before flowering
- perform a soil analysis if it occurs repeatedly
gray mold
The widespread weakness parasite Botrytis cinerea does not spare elderberry bushes either. During flowering, the risk of infection is particularly high. The entire plant is covered with a gray lawn of fungus. Red-brown spots develop on leaves and berries. The shoots hang limp, the fruits rot. The following treatment methods are possible:
- disinfect the infested soil with calcium cyanamide
- completely cut off diseased shoots
- Spray elderberry with Bayer Garten Obst Pilzfrei Teldor or Baycor
- Strengthen endangered elderberries with liverwort extract from March onwards
- Oscorna mushroom prevention or Myco-Sin have a preventive effect
- pay attention to an airy planting distance
- make an annual cut
Prudent care contributes significantly to the development of resistance to disease. This includes, in particular, never watering an elderberry over flowers and leaves, but always directly to the root area.
tips and tricks
The leaves of all elder species contain a glycoside that is not only toxic to humans. This ingredient penetrates the soil and inhibits the growth of other plants. Therefore, do not leave the autumn leaves in the garden, but burn them and dispose of the ashes in the household waste.