The secret to growing Augusta National-grade azaleas, according to a horticulturist

Azaleas are emblematic of the Masters, but they’re not exclusive to it. Relatives of rhododendrons, the flowering shrubs are native to several continents and flourish throughout the southeastern United States. At Reynolds Lake Oconee, about an hour east of Augusta National, thousands of azaleas are just reaching their peak. Kevin O’Shea is director of horticulture at the luxe golf destination. We asked him what he does to grow healthy azaleas, and how home gardeners can do the same.

1. Let there be (morning!) light

There’s nothing like waking up to sunshine. Azaleas enjoy it, anyway. Where you plant them matters, O’Shea says. They do best with ample morning light, followed by dappled shade in the afternoon.

2. Give a hole lotta love

Azaleas have shallow, fibrous roots that spread wider than they run deep. When you plant them, O’Shea suggests digging a hole that’s roughly three times the diameter of the bulb, then filling that hole with nutrient-rich, organic matter, such as peat, compost or chopped leaves. Azaleas do not do well in sandy or alkaline environs. O’Shea also recommends planting so that the bottom of the root bulb is roughly two to three inches above the soil line, and then building the soil up around the plant, “almost like a pitcher’s mound.” This will improve drainage, which is especially important if you’re planting in heavy clay soil.

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3. Don’t drown ’em

Azaleas are like golfers: they don’t like it when their feet get soaking wet. While moist soil is desirable, overly sodden soil can cause problems, such as fungus. Exactly how much you should water varies on a range of factors, including climate and soil conditions. But as a general practice, O’Shea waters his azaleas about two times a week throughout the first year, and three times a week after that. “Just watch out for standing water,” O’Shea says. “You don’t want to leave them in that.”

4. Pest prevention

Most of us are happy just looking at azaleas. Lace bugs prefer to eat them, gathering on the underside of the leaves and sucking out the nutrients. You can tell you’ve got a lace bug problem, O’Shea says, when the leaves get discolored, turning a mottled yellow. But you can also prevent that problem (or get rid of it if it occurs) with modest pesticide applications.

5. Prune before the end of June

Pruning is something of paradox: by cutting back, you promote growth. The best time to prune azaleas is during the ‘tweener phase, after the blossoms have faded but before the next year’s buds begin to form. As we know from the Masters, azaleas in the Southeast tend to hit their colorful peak in April. By May, the flowers are usually gone. It’s around that time that O’Shea and his staff bust out their pruners, aiming to get their work done before the end of June. “Our rule is not to prune after July 1,” he says.

6. Lay down pine straw

Scattering pine straw around the azaleas — it’s good for the soil. But, O’Shea cautions, don’t let the pine straw touch the trunk of the plant itself or it can prompt root rot.