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9 Best Fertilizers for Azaleas + Feeding Guidelines

9 Best Fertilizers for Azaleas + Feeding Guidelines

The azalea is a beloved and widely used ornamental plant in the United States for good reason. These plants not only add beauty to any setting, but they are also easy to care for and can thrive in a variety of Growing Zones.

What is the best fertilizer for azaleas? The best fertilizer for azaleas is an organic, slow-release acidic fertilizer. Liquid fertilizers can also be very useful for plants that need nutrients immediately or to support flowers just before blooming. However, as they require frequent application, this means more work for the gardener. 

When used correctly, fertilizing can be a straightforward, easy way of improving plant health, color, vigor, and of course, the abundance of blooms. 

Best Fertilizer for Azalea

All-natural, organic fertilizers are becoming more and more popular, and using them on your azaleas is recommended.

Why choose organic? Chemical fertilizers contain compounds that make plants dependent on them, so once you stop fertilizing, plants can suffer greatly.

Organic fertilizers on the other hand, simply act as additional nutrient boosts and also help to build up healthy soil so that year after year your garden will thrive.

What To Look For – General Guidelines

Look for fertilizers that are slow-release formulas. This will allow you to spread once in a season, and these are by far the easiest to use.

Liquid or powder fertilizers also have their place, and for those who don’t mind the repeated applications, these provide a fresh and constant supply of nutrients.

Keep in mind that applying the correct amount of fertilizer is key to ensuring your plants stay happy and healthy as too much can produce burned roots, and too little can result in nutrient deficiencies, both of which stunt growth and harm plants.

Liquid fertilizers are especially fickle, and it can be somewhat of a learning experience getting the ratios right, but if you follow product instructions carefully, you should be in the clear!

1. Espoma Organic Azalea-tone

This one hits all the marks when talking about fertilizers that are ideal for azaleas. It is a slow-release blend and acidic, and it comes in easy-to-spread granules.

This fertilizer contains bio-tones (bacteria that help make nutrients available for plants to take up), which makes this product great for newly planted azaleas.

It’s an excellent choice for growers looking for a spread-and-forget fertilizer that acts quickly.

2. Espoma Organic Holly-tone

Another superb fertilizer from the Espoma company, this product is an all-purpose formula and is suitable for all acid-loving plants, so it’s good for gardeners who have many different plants in their garden.

Espoma Organic Holly-tone also produces a more intense, green color in foliage.

3. Miracle-Gro Azalea Plant Food

Specifically created for azaleas, this product is great for gardeners who prefer to use a liquid spray fertilizer. This is a fast-acting plant food that reaches roots fast and is also very affordable.

Unfortunately, this fertilizer is not organic, and this should be taken into account.

4. Dr. Earth’s Organic Acid Lovers Fertilizer

The benefit of this fertilizer is that Dr. Earth is a reputable brand that is committed to sustainable gardening and has received many testimonials reporting fantastic results.

This is also a great organic fertilizer that can be used on all acid-loving plants in the garden, minimizing the number of garden products you need to keep at home!

5. Nelson NutriStar Azalea Food

A great product to use for boosting nitrogen and iron, this slow-release fertilizer won’t damage roots.

Nelson NutriStar is also useful for adding to potting and seedling mixes as it is very mild and created for optimal plant feeding.

6. Schultz Azalea Slow-Release Plant Food

This all-purpose fertilizer is not only great for azaleas, but it can also be used on fruit trees and vegetables. A low fertilizer-to-water ratio means less money per square meter spent on fertilizing. 

7. Ferti-Lome Azalea Food

This fertilizer is a powerhouse; it provides nutrients and acts as a deterrent against a huge range of pests.

Helping to control aphids, leafhoppers, leafminers, thrips, whiteflies, and many more insect infestations, this is definitely a product to keep in mind.

8. Pennington UltraGreen Azalea Food

Pennington UltraGreen is an excellent product to use in gardens that receive less rainfall as it contains a formulation of water-retaining ingredients to prevent dehydrated plants.

This fertilizer also helps to prolong plant blooms, giving you enjoyable, vibrant flowers for longer.

9. Jobe’s Organics Azalea Food

This certified organic fertilizer is a favorite among growers of azaleas, both in the garden as well as in pots, and a lot of success has been accredited to this formula.

Jobe’s Organic Azalea Food also helps to feed beneficial bacteria in the soil to create healthy, strong, and resilient plants.

Fertilization Guide for Azalea

A multitude of bright-pink azalea flowers.

All manufacturers have their own guidelines for specific products, and following this will ensure you are using the product correctly.

However, there are some general tips to help you. Read on to find out.

When To Fertilize Azaleas

Feeding azaleas in spring at the first sign of blooming will give plants the boost they need for vigorous growth and bright, attractive flowers.

To avoid any sun damage, apply fertilizer in the evening, watering it in thoroughly.

Alternatively, you could apply fertilizer right before a moderate rainshower, and let nature do the watering for you.

How Often To Fertilize Azaleas

As a general guide, slow-release fertilizer should be applied in spring and again in fall but at half of the spring rate.

Fertilizers should always come with instructions for usage, and products will vary with how much should be used in the garden and at what frequency.

When Not To Fertilize Azaleas

Avoid spreading fertilizer during hot periods, and only use liquid fertilizers or products like Nelson NutriStar Azalea Food on young or newly-planted azalea.

If plants are showing signs of too many nutrients, fertilizing should be immediately halted and resumed only when plants return to healthy coloration.

Homemade Fertilizer for Azalea

Composting at home is very easy, and when using your own garden and kitchen waste, you are looking at the best option out of all fertilizers for your azaleas — organic, free, and packed with incredible nutrients.

Making compost tea is also a great way to produce your own affordable and effective liquid fertilizer.

Simply fill a container with water, add finished compost, and let sit for two days. Then, drain the solids, and the dark caramel-colored water left is a nutrient-rich yet mild liquid fertilizer. 

Coffee grinds can also be a great acidic supplement for azaleas; however, they should be applied moderately, around once every three weeks, as an excess can result in burned roots and excessive acidity.

Related Questions:

When Should You Prune Azaleas?

Pruning azaleas can be undertaken at any time of the year, making sure that pruning shears have been sanitized before use with either rubbing alcohol or a 1:9 bleach solution and washed off before cutting. 

To avoid removing growing buds and ruining your flower display for the year, wait until blooming is over before doing any major pruning.

How Long Do Azaleas Live?

Azaleas can be quite long lived, especially when given the right conditions to thrive. Some specimens can live to 30 years.


Keeping azaleas is a rewarding experience, and with little effort, you can grow healthy, beautiful plants.

Because there are so many cultivars, finding an azalea with just the right color, height, and shape for your space can be an exciting and straightforward process.

Fertilizing can take some time to get right, but it will be worth the effort when deep, rich foliage and impressive blooms of color greet you from the garden.