What your Azalea Needs in March to Survive, Thrive & Grow Abundant Flowers: 4 Vital Tasks to Do This Weekend

Azaleas are the epitome of spring, the arrival of their vibrant flowers a sure sign that the warmer weather is finally here. With native azalea species bursting into life up and down the country, as well as thousands of different cultivars greening up in our gardens, this plant is preparing to put on a spring parade of fabulous flowers – and what you do with your azalea in March will dictate if it’s a joyous spectacle or just a so-so show.

April is regarded to be the prime month for peak azalea blooming, which is why March is so crucial for azalea care. However, with so many different varieties and species, and a huge variation in climates depending on your USDA zone, azaleas can flower as early as February. So if your azalea is already in full bloom, bookmark this article for next year.

Otherwise, it’s high time you got cracking! These four vital azalea care tasks are easy, even if you're a beginner gardener. Give your azalea the TLC it needs now and you’ll be rewarded not only with a fabulous show of flowers this spring but better long-term growth that will lead to abundant blooms in the years to come. Azaleas are long-lived perennial shrubs and with the right care, they can live for over a hundred years. So it’s well worth investing a couple of hours of your time this weekend to ensure your star spring bloomer is happy and healthy. Here’s exactly what to do.

1. Treat Your Azalea To a Fresh Mulch

Azaleas thrive in slightly acidic soil that’s moist but well-drained, and the very best way to provide your plant with these conditions is to mulch in early spring. This will provide nourishment over a long period, and lock moisture in while improving soil structure for good drainage. Azaleas evolved as woodland-edge plants so your aim is to recreate a forest floor with a fresh layer of plant material added every year.

Choose a mulch that’s naturally acidic – pine bark mulch, available from Amazon, is a great option. You can easily make your own mulch, too. Many folk save the pine needles from their Christmas tree to lay as a mulch beneath their azaleas, and it’s fine to use them fresh or dried. If you’re lucky enough to have an oak tree in your garden then use their naturally acidic leaves to make leaf mold for a rich mulch. It’s easy to do with a Geobin Compost Bin from Amazon that can be expanded to suit how much leaf mold you want to make.

Apply a 1–2 inch layer of mulch on the soil around your azalea, keeping it away from central stems. A bow rake such as this one from Amazon is the best tool to use as you can spread the mulch with the tines then flip it over to level the surface with the flat edge.

Azaleas are shallow-rooted plants, so this layer will also help to cushion roots from any extreme temperature fluctuations, too.

2. Don’t Fertilize Unless Your Azalea Tells You it’s Necessary

Azaleas flower on old wood. This means that this year’s blooms grow from buds that were set on last year’s stems. So fertilizing your azalea now won’t bring you any more flowers this summer. The mulch you’ve applied will provide an established plant in the ground with all the nutrition it needs, so there’s no need to routinely fertilize it at all – unless your azalea tells you otherwise. And then, only fertilize to correct a problem.

Many more azaleas have been killed by kindness than they have by neglect, and over-feeding this shallow-rooted plant can quickly lead to root damage, fertilizer burn where the leaf tips turn brown, excessive weak growth that attracts aphids, or stunted growth.

If your azalea is giving you any cause for concern, then test your soil to discover where the problem lies. An inexpensive mail-in kit such as this MySoil kit from Amazon will give a far more detailed analysis than those that rely on test strips for results.

A common issue with plants that love to grow in acidic conditions is chlorosis, where the leaves become yellow with green veins. This is typically caused by an iron or manganese deficiency, and often happens when these plants are grown in alkaline soil, where these elements are less available. The solution here would be a slow-release fertilizer that provides these nutrients and also a soil acidifier to ensure they’re available to the plant, such as this Gardenwise fertilizer for acid-loving plants from Amazon.

According to the Azalea Society of America, the best time to fertilize an azalea is in early spring.

The only exception to this rule is if your azalea is a rebloomer, such as the Encore and ReBLOOM series. These flower a few times through spring and summer, so it’s recommended to fuel these extra energy requirements with a slow-release fertilizer applied right after you spot the first spring bloom. Use a feed that supports whole-plant health rather than simply promoting flowers, such as Holly-Tone, available from Amazon.

3. Nourish a Potted Azalea With Long-Term Goodness

Potted azaleas need a slightly different approach, as they can only access a limited amount of soil to get their nutrients. Every year in early spring, topdress the pot by scraping off the top inch or two of compost, being very careful not to damage the shallow roots – a chopstick is useful to loosen compacted soil – and replace with fresh ericaceous potting soil such as this Planting Soil for Acid-Loving Plants from Amazon.

Every two or three years, repot your azalea instead, moving it into a pot one size up, also using ericaceous compost.

You can also feed a potted azalea, just once with slow-release granules such as Shultz Plant Food from Amazon, or every few weeks with a soluble liquid fertilizer like HiThrive Fertilizer, also from Amazon. Do make doubly sure it’s a feed specifically for acid-loving plants, and don’t fertilize after the end of June or new growth won’t be winter-hardy. Don’t overdo it either – if you see a white crust forming on the soil surface, it’s likely an accumulation of fertilizer salts which indicates you’re over-feeding.

4. Water, with Rainwater if You Can

The element that will bring you more azalea flowers isn’t food, but water. And if you can water with harvested rainwater that’s naturally slightly acidic, all the better. Mains water is usually treated to be slightly alkaline to prevent pipe corrosion and, over time, this can change the pH of your soil. This can affect the health of your azalea, particularly if you live in a low-rainfall area where elements from mains water accumulate in the soil rather than being regularly washed out by heavy rain. It's also an issue for potted plants, which are watered more often than those growing in the ground.

So, even if you only harvest enough rainwater solely to water your azalea, it’s worth the effort. You can find solid-sided rain barrels such as these from Home Depot for less than $100, or Wayfair currently have these smart faux-stone rain harvesters on sale.

The trick to get more flowers is to not just water while your plant is in bloom, but to continue watering through summer. This is when your plant sets its buds for next year’s blooms and, if it’s well hydrated, it’ll make more flowerbuds.

Azaleas hate to have their roots sitting in water though, so be careful not to overwater. Good drainage is essential, and regular mulching will take care of that if you’re growing your azalea in the ground. In a container, raising the base up on pot feet allows water to drain far more freely, and will make all the difference in a wet spring.

Reliable Risers For Potted Azaleas

And there you have it, a happy azalea that will bloom abundantly and grow lots of new flowerbuds for another year of spring joy. Azaleas don’t need deadheading or pruning, though you can tidy leggy stems up straight after it’s finished flowering if you like, so you’re done for the year!