Brown leaves and wilted leaf tips on hydrangeas require immediate action. The picturesque splendor of flowers is absolutely dependent on the supply of healthy, vital foliage. Since the damage results from a variety of causes, you cannot avoid a detailed analysis. Only precise knowledge of the trigger enables effective countermeasures. These instructions explain how you can gradually approach the actual cause in the process of elimination and successfully eliminate it.

cause drought

Root cause:

  • dryness

Solution:

  • pour copiously

The scientific name Hydrangea refers to an essential characteristic of the hydrangea and means water bush or water slurper. Consequently, one of the key functions in a professional care program is an adequate supply of water, adapted to the season, the soil conditions, the location and the current temperatures.

Primarily during hot summer days, there is a rapid lack of water, as a result of which the hydrangea leaves turn brown from the tips, dry up and fall to the ground.

These immediate actions fix the problem:

  • water immediately in the bed
  • Run lime-free water directly onto the root ball until small puddles form
  • Soak the hydrangea in the pot with the root ball in soft water until no more air bubbles rise

From now on, water your hydrangea whenever the soil has dried on the surface. Don't wait for wilted leaves and flowers to droop. Irrespective of the high water requirement, waterlogging must not occur. As soon as you can see that the soil is not absorbing any more moisture, stop watering. Thirst is quenched in the pot when the saucer fills up.

cause sunburn

Root cause:

  • sunburn

Solution:

  • relocation

If hydrangeas are exposed to the blazing sun at midday, sunburn is inevitable. As a visible symptom, light brown and yellow spots appear on the leaves, starting from the leaf tips. Typically, these spots stop spreading once the sun's rays have passed. Rather, the rest of the leaf tissue remains green.

The following troubleshooting options are available:

  • transplant a shrub in the bed to a semi-shady, sheltered location
  • alternatively shade with a parasol at midday in summer
  • Pots move to a place without direct sunlight

Do not cut off the affected hydrangea leaves. The green tissue continues to make an important contribution to the supply of the flowers.

Cause Damage caused by late frost

Root cause:

  • Damage from late frost

Solution:

  • cover overnight

After a mild winter, hydrangeas sometimes sprout as early as the end of February. If the ground frosts are delayed as a result, the leaves at the tips of the leaves turn brown. As if that weren't enough, the buds planted the previous year can freeze to death, preventing them from developing into the magnificent flowers.

How to act correctly in an emergency:

  • Cut off frozen hydrangea leaves
  • from now on cover the shoots every evening
  • Breathable, translucent fleece or jute ribbons are suitable

During the day, remove the cover to allow your hydrangeas to continue their normal growth process unhindered. As long as the meteorologists announce nightly frosts, the bushes get the protective coat.

Cause leaf spot disease

Root cause:

  • leaf spot disease

Solution:

  • Remove brown leaves, apply fungicide, improve general conditions

If your hydrangea gets brown leaves, it is not uncommon for the widespread leaf spot disease to be behind it. Triggers are fungal pathogens of various origins. Typical symptoms are dark yellow leaf spots around a brown center. As the infection progresses, the spots merge, the entire leaf turns brown and dries up. Fatally, the infection strikes in any weather, since it is not a special type of pathogen.

Here's how to take action against the disease:

  • Cut off all infested hydrangea leaves and dispose of with household waste
  • isolate a hydrangea in the tub from other plants
  • treat the affected flowering shrub with a fungicide such as Compo Duaxo Universal Fungus-free

Unfortunately, using a fungicide only superficially fixes the problem. The pathogens could only attack the hydrangea because it was weakened due to unsuitable conditions. This includes in particular that hydrangeas should not be watered. Permanently moist leaves offer fungal spores a welcome target.

A nitrogen-stressed fertilization weakens the resistance of the flowering shrubs as well as waterlogging, dry balls and lack of light. Regular spraying with horsetail broth and liverwort extract has proven to be an excellent way to protect the ornamental tree against diseases.

Cause leaf chlorosis

Root cause:

  • Leaf chlorosis due to iron deficiency

Solution:

  • Epsom salt and improved water quality

The dilemma starts with yellow leaves and green veins. In the further course, the hydrangea stops growing almost completely. This damage is mostly due to iron deficiency. Although there is an abundance of iron in every normal garden soil, the micronutrient no longer reaches the pathways.

The cause is an excess of lime, as a result of which iron and magnesium are fixed. Not only hydrangeas are affected, but all ornamental and useful plants that depend on an acidic pH value in the substrate.

If you can diagnose iron deficiency as the cause, correct the problem as follows:

  • From now on use only lime-free water for watering
  • remedy the acute iron deficiency with Epsom salt or a special iron fertilizer for flowering plants
  • change the nutrient supply to acidic coniferous or leafy compost
  • repot a hydrangea in a tub in bog bed substrate

Please do not use iron fertilizers that are sold in specialist shops for combating moss in the lawn. Not only is this fertilizer unsuitable for flowering shrubs, it also contains highly toxic ferrous sulphate that is harmful to your health and the environment. You are better advised to use high-quality products such as Substral Osmocot rhododendron and hydrangea fertilizer or Compo rhododendron slow-release fertiliser.

For hydrangeas in pots, the specialist trade has iron chelate fertilizers ready, such as Fetrilon from Compo. These products contain no ferrous sulfate and are diluted with water for easy administration.

Cause spider mites

Root cause:

  • spider mites

Solution:

  • Home remedies and insecticides based on rapeseed oil

If causes from the areas of location, care and disease can be ruled out, pests as the trigger for brown leaves and wilted leaf tips come into focus. Spider mites should be mentioned primarily. The 0.25 to 0.8 mm small insects love a warm, dry climate in order to multiply explosively in the garden, on the balcony or in living rooms. Among the more than 1,200 species there are green, yellow, red and orange specimens that only catch the eye in larger hordes.

Spider mites pierce the leaves with their mouthparts and suck up the plant sap. In the early stages of infestation, a leaf is covered with silvery speckles on the surface. It then turns yellow, later grey-brown and falls off when dry. Typical of the widespread common spider mite are fine, white webs on the underside of the leaf. Once you have identified the pests as the cause, the following control methods are available to you.

shower off

Hydrangeas are strong enough to withstand a stronger water jet. The spider mites, on the other hand, are attacked with a shower. Therefore, shower the infested shrub several times. To protect against waterlogging, cover the root disk in the bed with foil. For potted plants, pack the root ball in a plastic bag tied to the root neck with string.

soft soap solution

In the early stages, spider mites on hydrangeas have nothing to oppose a proven home remedy. The soft soap solution works effectively against biting and sucking pests of all kinds.

You can make the environmentally friendly insecticide yourself using this recipe:

  • 1 liter of boiled water
  • 15 milliliters of soft soap or liquid curd soap
  • 15 milliliters of strong alcohol

Experience has shown that a single application is not enough. Therefore, spray the soapy solution on the top and bottom of the hydrangea leaves every 2 to 3 days. Ideally, apply the home remedy in the early morning hours so that the leaves have dried by the evening.

rapeseed oil

If your hydrangea is being plagued by a stubborn spider mite colony, ramp up the guns with a canola oil-based insecticide. Products such as Naturen Bio-Schädlingsfrei or Pflanzen Paral Schädlingsfrei S are ready to use. The innovative insecticide Neem Plus Schädlingsfrei combines the effects of rapeseed oil and neem, which kills even hardened spider mites without having to resort to chemical ingredients.

Category:

Garden plants