Hydrangeas are the flower-rich focal points in many gardens. The flowers shine in many shades - from white to soft pink and intense pink to blue - and attract many eyes. They also bring colorful variety in the garden or on the balcony. If hydrangeas throw off leaves and flowers, they quickly become a sad sight. With the right countermeasures, the underlying causes can usually be remedied quite easily.
Substrate
Hydrangeas have very high demands on the substrate. It has to be loose and fibrous, but also be able to store water well and not condense or wet it. To do this, the plants need an acidic pH value of 4 to 5.5 - depending on the color of the flowers.
Therefore, if the hydrangea sheds leaves and flowers, a problem with the substrate should be considered first. It is advisable:
- test the pH
- to check the condition
- carry out an earth change if necessary
Regular repotting is urgently needed, especially when it comes to pail culture. The hydrangeas should not be in the same soil for more than two years.
Tip: Anyone who is unsure about the choice of substrate or the mixture can fall back on special soil for hydrangeas and azaleas from specialist shops. This meets all requirements of the plants.
dryness
Hydrangeas have a large demand for water. Regular watering is particularly important in the growth phase and especially during the flowering period. If the leaves are hanging, they appear limp and withered, the substrate should be checked. At most the top layer should be dried out and crumbly.
After that, the earth should appear moist. This cause of the loss of leaves and flowers is very easy to fix, because it simply has to be watered more. If drought keeps coming back, a few simple tips can help
- switch to substrate, which stores moisture better
- Apply bark mulch to the earth
- Cover the substrate with stones or garden foil
These measures reduce evaporation and the soil is kept moist for longer. If the water is then poured in a floating manner so that the substrate can soak up properly, the drying out and thus the loss of leaves and flowers can be prevented.
lime
Hydrangeas like a slightly acidic substrate and should therefore only be watered with soft - i.e. low-lime - water. Rainwater and stale tap water are ideal. If this has not been taken into account, the plant can also shed leaves and flowers as a result.
The appropriate countermeasures consist of changing the substrate and using rainwater in the future. If it is difficult to change the substrate, acidifying fertilizers can also be used. Sulfur and iron sulphate can be used in heavy, compacted soils. Coffee grounds are also suitable for slightly acidifying the substrate.
Organic agents can increasingly be used in loose soils. Compost and rotten oak leaves are particularly suitable. During these measures, the pH of the soil should be measured repeatedly in order to check success and to avoid over-acidification. It is also important to work the chosen agent evenly and thoroughly into the surface of the substrate and then pour it well.
Wetness
Hydrangeas need a lot of water, but the plants do not tolerate waterlogging. In the bucket you should therefore be very careful that the plant is not in the water. Planted freely in the garden will be a little more difficult to control. However, a small excavation can provide information.
In the case of soil tending to compaction and
- Quartz sand, this improves the drainage of water
- Coconut soil
- Perlite
- sand
How much of it has to be added depends on the initial state of the substrate. It can also be useful to add a drainage layer made of pottery shards in the bucket.
Nutritional deficiency
If a lack of nutrients is responsible for the shedding of leaves and flowers, this is usually an undersupply of iron or nitrogen. However, both are relatively easy to identify and fix.
Nitrogen deficiency
If there is a lack of nitrogen, the older leaves will first turn yellow. This means that the plant turns yellow from the bottom up and from the inside out. A nitrogenous fertilizer can help here. If it is given over the substrate, however, the compensation can take several weeks. It is therefore particularly suitable when yellowing and leaf shedding have not progressed too far.
If, on the other hand, it has to be done quickly, as the plant is already showing considerable losses, a foliar fertilizer should be used. The nutrients are absorbed in this form in a significantly shorter time, as they do not have to take the "detour" via the roots.
Iron deficiency
A yellow coloration of the leaves is also typical of the iron deficiency. Here, however, the leaf veins are still green. This condition is known as chlorosis. After the discoloration, the hydrangea sheds leaves and flowers. So here too, action should be taken quickly.
Suitable antidotes are:
- Iron chelate
- Iron fertilizer
- Blood meal
In addition, if there are signs of iron deficiency, it should be ensured that the pH value of the substrate is in the acidic range. Otherwise the absorption of nutrients and minerals can be more difficult.
fertilization
Apart from the mentioned deficiencies, the hydrangea can also be generally undersupplied. The right fertilization can help here. It is particularly easy to use special hydrangea fertilizers. The manufacturer's instructions should be followed for this. In the bucket culture, part of the nutrient supply can also be ensured through regular substrate changes. Exchange every one to two years is ideal. If the soil is of poor quality, it should be changed every year.
Pests and diseases
In the hydrangea, spider mites and the leaf spot fungus are primarily responsible for the shedding of flowers and leaves. In both cases, the leaves become blotchy and eventually brown before falling off. In addition, the plant is generally weakened,
so that the loss of flowers can be foreseen. Here, too, it makes sense to act quickly against the infestation in order to limit the damage to the hydrangea and also to prevent the fungi and pests from spreading to other plants.Spider mites
The leaves turn brown and often curl up. Greasy stripes and woven webs are visible. A spider mite infestation is relatively easy to see if you look closely. The fight is not that simple, but requires a little more effort. The infected leaves should be cut off or collected and destroyed or disposed of with household waste. Appropriate means should be used immediately to prevent further damage.
Spider mites are one of the most difficult parasites to fight against - it has to be with the Destruction of the leaves and the use of the chosen means therefore proceeded comprehensively and thoroughly will. It also helps to check the culture conditions. The spider mites like it dry and warm. Occasional spraying has a preventive effect in very dry locations.
Leaf spot fungus
The same procedure should be followed for leaf spot fungus as for spider mites. Infested leaves must be destroyed so that no further spread can take place. Leaves that have already fallen should also be collected and disposed of accordingly.
A fungicide must also be used. It also helps to check the location for suitability. If the hydrangea is in a very humid environment and particularly windless, the mushrooms have easy time.
cold
Frostbite is not uncommon for hydrangeas. If shoots were exposed to freezing temperatures, they not only shed leaves, but also die off completely. Exceptions here are particularly frost-hardy varieties such as individual panicle hydrangeas - these can withstand temperatures as low as -30 ° C without any problems.
For everyone else, frost protection made of brushwood, straw and garden fleece or taking them indoors is mandatory.
prevention
If deciduous hydrangeas shed leaves and flowers outside of autumn, this is always an indication that care is not optimal. It therefore makes sense in any case to check all influences and adjust them if necessary. The following points can help:
- Check location for suitability, neither too dry nor too humid
- Examine the substrate and test the pH
- Check the humidity of the substrate
- regular visual inspections of the crops
- Use water with little lime
- fertilize regularly
- change the substrate at least every two years in the case of bucket culture
Conclusion
When hydrangeas shed leaves and flowers, you need to act quickly. The causes are usually relatively harmless, but still require appropriate countermeasures. The best prevention is the strengthening of the plants through optimal cultivation conditions.
