If you are saying the individual plants themselves are 12' mounds you get that effect by having them live long enough to produce a specimen of that stature.

There are several ways. One is to raise a plant for a long time that spreads as it grows until it becomes that big. Since that take a long time, the more common way is to plant a clump of azaleas. This gives you the opportunity to mix varieties if you want to. When I say clump, I mean more than one plant. They wouldn't be planted close together, but would be planted far enough apart so that they would grow together in 10 years or so. One way would be to plant an 8' diameter ring of 5 plants 5' apart or 6 plants 4' apart. Then plant a single plant in the center. You would want to pick the tallest plant for the center. The larger the plants were when you planted them, the quicker it would fill in.

You would need azaleas that will eventually grow tall. Here are some of the taller varieties:

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Formosa (Phoeniceum) - 6', +10F. Blooms in mid-season. Has a tall upright plant.

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George Lindley Taber - 5', -5F. Blooms in mid-season. Medium height.

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Pride Of Dorking - 5', +10F. Late blooming. Meidum height.

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Pride Of Mobile (Elegans Superbum) - Blooms in mid-season. Has a tall upright plant.

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White Lace - Vigorous plant habit.

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Delaware Valley White - 6', 0F. Blooms in early mid-season.

Here is a link that might be useful: Heat Tolerant Evergreen Azaleas

Dear rhodyman,
Although you have posted photographs of some of the hardier and more familiar Southern Indian azaleas, none of the Indian azaleas can tolerate temperatures of five or six degrees below zero Fahrenheit. At those temperatures, bark will split and the plants will die. Frankly, with sufficient time, a single Indian azalea will grow into the size described in the original posting. There's a Formosa azalea in our yard that was planted in the 1960's. It now has a huge circumference and an astonishing height--one plant that has spread by tip-layering over the past forty-some-odd years to form a large Formosa colony.

Does South Mississippi get 5 or 6 degrees below zero Fahrenheit? We seldom get that cold here in Pennsylvania.

As I said, you can either raise one plant for a long time, or you can get quicker results in a short time with several plants. Most people that are planting now are looking for the quicker results.

Dear rhodyman,

Ah, yes, instant gratification in all things.

The fact that the Mississippi Gulf Coast does not routinely experience negative five degrees Fahrenheit is irrelevant to the fact that _Rhododendron indica_ 'George L. Taber' cannot survive that low a temperature. I am merely pointing out an obvious error in fact. Sorry if that stung a little.

Some ares have bark split problems much worse than other areas. Areas with early springs and late frosts obviously get hit very hard. But so do areas where plants are slow to harden off and get a late frost. So even a very hardy plant will get bark split if it hasn't hardened off before a heavy frost.

Hardiness information is normally separate from bark split information. The two are only obliquely related. Bark split depends upon either when the sap starts rising and when the last frost hits or when the sap stops rising and when the first frost hits. Bark split tends to hit the area around North Georgia/South Carolina the hardest. We seldom see in further north.

Hardiness is usually dependent on temperature only. For example, PJM is one of the hardiest rhododendrons in the world, but often has its early blooming flowers hit by late frosts. It is still considered hardy, but not especially popular in areas with frosts that hit during its bloom season. Similarly, Geo. L. Taber would not be popular in areas that had frosts when it wasn't dormant and its sap was rising. I don't think South Mississippi is one of those areas.

Regarding hardiness for the evergreen azalea George Lindley Taber, I don't raise that plant. However, I have friends here in PA and nearby in NJ that do raise it. In fact it was selected the best evergreen azalea in the Valley Forge Chapter ARS Flower Show last year. My reference for the hardiness is the ARS Azalea of the Year description is:

"Evergreen Azalea: 'George Lindley Taber'
sport of R. 'Omurasaki'

Flower white flushed moderate purplish-pink, lighter at margins with a darker blotch and moderate purplish-red spots, openly funnel-shaped, 3" across. Blooms midseason. Leaves elliptic, 1" long, light green. Upright, spreading habit. Reaches 4-6 ft. in 10 yrs. Hardy to -5 F (-21 C). Selected by Hume. Named by G. Tabor, Jr."

Dear rhodyman,
I'm going to decline the opportunity of searching out an authoritative document that disputes your contention that 'George L. Taber' is cold hardy to negative five degrees Fahrenheit. I don't have time to do that; however, I do think that the preponderance of horticultural opinion counters your claim. Do note that your cited document contains a misspelling of the surname _Tabor_, at least in the context of rhododendrons. That error casts suspicions on your source. As to 'George L. Taber' flourishing, or even surviving, north of the Mason-Dixon Line--yes, in a conservatory at Longwood Gardens, but very doubtful in a "normal" Pennsylvania or New Jersey landscape--unless the gardener performs extraordinary measures to pull this variety through a "normal" Northern winter.

Re: South Carolina's climate. In SC, there are the mountains, the Piedmont, the sandhills, and the coastal plain. (The sandhills are a part of the upper coastal plain.) The Fall Line divides the Piedmont from the coastal plain. Traditionally, we Carolinians have referred to the coastal plain as the Low Country, and the Piedmont as the Up Country. There are climatic differences between these regions. The Piedmont and North Georgia have similar climates. The Low Country, on the other hand, has a milder climate that is similar to that of the Mississippi Gulf Coast. Your posting fails to acknowledge the difference in the climates of our state.