Caring for Rhododendrons and Azaleas

By August 26, 2020February 9th, 2021No Comments

Rhododendrons and AzaleasAzaleas and rhododendrons are a beautiful addition to a garden. Azaleas and rhododendrons can be grown in any garden. You’ll find it easy to add plants to a landscape.

However, it’s important to care for azaleas and rhododendrons and keep them healthy during the growing season.

Proper Azaleas and Rhododendrons care program includes the following:

  • Garden soil care
  • Fertilizing
  • Pest and disease control
  • Trimming
  • Watering

If you grow and care for azaleas and rhododendrons correctly, plants will look healthy and impress you with an abundance of beautiful blooms.

Today, we’ll talk about the most important aspects of caring for azaleas and rhododendrons.

Caring for Azaleas

Azaleas are easy to grow and easy to care for plants. Azaleas need to be planted properly because they grow better in lightly shaded sites.

Azaleas have the most attractive look when planted alone. However, if you would like to grow Azaleas in wooded sites or larger areas then it would be better to do mass plantings.

Picking the Right Soils for Azalea Plants

Azaleas are the plans with shallow roots. So, it would be better to grow them in well-drained acidic soil.

It’s a good idea to add organic matter or mulch to the soil where Azalea plants are grown. Mulch provides the plants with the nutrients they need. As a result, you’ll not need to fertilize

Azalea plants frequently.

You can also add small amounts of nitrogen to the soil either in late spring or early fall. By doing so, you’ll be able to solve a nutrient deficiency problem and promote the growth of Azalea plants.

Azalea Diseases and Pests

Insects don’t affect Azalea plants frequently, but some pest and disease control may be required.

Among the most common Azalea diseases are:

  • Leaf spots
  • Root rot

In order to minimize the risk of Azalea diseases, you should grow the plants in the areas with good drainage.

Plus, you should apply mulch to the areas where Azalea plants are grown. This will help you reduce the plant damage significantly.

Among the pests that attack Azaleas are:

  • Lace bugs
  • Spider mats

Oftentimes, pests attack Azalea plants if they are grown in places with full sun.

Trimming Azalea Plants

Azalea plants need to be trimmed after the blooming season ends. The branches of shrubs have to be cut back.

Trimming has a positive impact on blooming Azalea plants. That means that plants are likely to bloom much better the next season if they are trimmed properly.

Trimming is done to renew overgrown plants. It’s also important to note that trimming helps keep Azaleas healthy.

Caring for Rhododendrons

The best time for planting Rhododendrons is either spring or early fall. It’s crucial to plant Rhododendrons in the right places.

The plants grow well in:

  • the areas with acid soils
  • the areas which are rich in organic matter
  • the areas which are protected from drying winds
  • the areas which are protected from hot sun

On the other hand, Rhododendrons shouldn’t be planted:

  • in dry soils
  • under trees that have a large root system
  • in the shaded areas
  • close to foundation
  • under roof overhangs

And of course, like any plant Rhododendrons require special care. Now, let’s take a close look at the maintenance of Rhododendrons.

Garden Soil Care for Rhododendrons

It’s incredibly important to create the ideal conditions for growing Rhododendrons. The question is – what type of soil do plants need?

The plants grow normally in:

  • acid soils
  • alkaline soils
  • heavy soils
  • well-drained soils
  • soils rich in organic matter
  • soils rich in pine needles
  • pine bark with or without soil

Keep in mind that the soil for growing Rhododendrons needs aerating. Soil aeration is key to the successful growth of plants.


Fertilization of soil in which Rhododendrons grow is usually not required if plants have enough nutrients for normal growth.

When soil lacks the necessary nutrients, plants have yellow foliage. The growth of plants slows down as well. These are the signs that fertilization is required.

Fertilizer is applied when plants grow in less fertile soil. Fertilizers, which are designed for acid-loving plants, work very well for Rhododendrons. Nitrogen is usually added to the soils in which the plants grow.

Such fertilizer as ammonium sulfate can also be used to support the growth of plants.

Let’s say that soils lack phosphorus. In this case, a fertilizer with this element should be applied to incorporate phosphorus into the soil.

Sometimes, it’s necessary to incorporate such elements as calciumiron as well as magnesium into the soil.

It makes a lot of sense to do soil testing ahead of time. This will help you decide what type of fertilizer is needed for your garden.

It’s also very important to use the right amount of fertilizer for Rhododendrons.

Using too much fertilizer can burn the roots and cause damage to plants. On the other hand, plants will not get enough nutrients if less fertilizer is used.

Pay close attention to the recommended amount of fertilizer for Rhododendrons in your area.

It’s a good idea to use mulches for the areas where the plants are grown. Fresh sawdust or wood chips work very well for Rhododendrons as well.

Pest and disease control

Pets pose a serious threat to Rhododendrons. They feed on the plant’s stem and roots.

If not treated properly, pets can even kill the plant over time.

Root weevil is the biggest enemy for Rhododendrons. The beetle is the most active in June.

The pest feeds on the plant’s root. If Root weevil is not controlled effectively, it can cause huge root damage to the plant.

When the beetle feeds on the plant’s stem, the stem weakens. The weakened stem can easily be broken over time.

If these kinds of things happen, you’ll find it difficult to save the plant.

Among the other pests that can cause damage to Rhododendrons are:

  • aphids
  • caterpillars
  • mites
  • scale insects
  • thrips

In most cases, sprays are used to control pests.

Rhododendrons can also suffer from various diseases. Different diseases can attack the plant.

These include:

  • Powdery mildew
  • Root rots
  • Rust diseases

You should do every single thing possible to prevent these diseases from attacking plants in your garden.

1) Make sure that plants grow in areas with excellent drainage.

2) Add mulch to the soil when such a need arises.

3) Protect your plants from cold properly.

4) Do a soil test. Add the necessary nutrients to soil based on the test if necessary.

5) Water plants on a regular basis.

Take all the necessary preventive measures to keep your Rhododendrons healthy and strong.

Watering Rhododendrons

Rhododendrons are known as drought resistant plants. However, plants have broad leaves. That’s the reason why they require more water.

Watering plays a very important role in the maintenance of Rhododendrons.

It’s worth noting that watering is particularly important for newly transported plants. The root system of newly transported plants actively develops. That’s why the plant needs more water.

It’s recommended to water Rhododendrons every few weeks. However, plants with big leaves require more frequent watering.     


Pruning is also a part of the plant’s maintenance. Sometimes, it’s necessary to cut off some of the plant’s branches.

Pruning promotes the re-growth of Rhododendrons and results in better flowering.

Pruning needs to be done after the end of the blooming season.

Do you need help with caring for Rhododendrons and Azalea plants? Contender’s Tree & Lawn Specialists would be happy to assist you with any of your needs!