Firestorm Rhododendron

OK, we admit it. Rhododendrons don’t grow fast. But speed isn’t everything, and in the garden it isn’t even always desirable. Fast-growing plants soon become weedy, and then tend to be short-lived. For a truly stable, mature look (and isn’t that in truth what we all want?) it’s best to look at plants that grow a bit more slowly, but deliver the goods. OK, reaching 3 feet in 10 years, like the Firestorm Rhododendron will, isn’t going to get into the Book of Records, but that will be 3 feet of solid, multi-stemmed growth. Your young plant will turn into a dense beauty, a broad ball of gorgeous foliage smothered in late spring by such an abundance of fire-red blooms you will hardly be able to believe it. And let’s face it, how long is 10 years in the garden? Not so long, right? Not so long when the reward is well, so rewarding. So forget the stats for a moment, and think of the beauty – it isn’t really a contest at all, is it now?

Growing the Firestorm Rhododendron

Size and Appearance

The Firestorm Rhododendron is a small to medium-sized evergreen shrub, with a rounded, slightly spreading growth form, and slow-growing. It will reach about 3 feet tall in around 10 years, and be a little wider, we could say about 4 feet across. It of course continues to grow after that, and will probably reach about 5 feet tall and 6 or even 7 feet wide in time. It has exceptionally dense foliage because the leaves remain green and on the plant for up to 3 years. This is in contrast with most other rhododendrons, which hold their leaves only 1 or 2 years, and so tend to be more open and show older branches as they mature. The Firestorm Rhododendron will instead be bushy, leafy and dense throughout its life. The leaves are 5 or 6 inches long, flat, smooth and straight-sided ovals. They are dark green. New growth in spring is, unusually, light, almost lime green, and the mid-rib of the leaf tends to remain light for years. This is all normal – and attractive – so don’t think it has an iron deficiency or anything like that. 

The foliage is a little unusual, and the Firestorm Rhododendron doesn’t stop being special with just that. It flowers late in the season, keeping your spring display going strong for several more weeks. Carried in enormous trusses containing up to 16 booms, and with many clusters even on a small bush, ‘firestorm’ is the perfect description for these amazing blooms. They are the most brilliant red, with each flower up to 3½ inches across, with wavy edges. Each flower is solid red, undiminished by any of the spots, splotches and lighter areas seen in a lot of rhododendrons. Truly a glory to behold, and enough to bring tears to the eyes of any lover of red flowers.

Using the Firestorm Rhododendron Arborvitae in Your Garden

Whenever you grow more than one variety of some plant, it really pays dividends to mix early, middle and late-blooming varieties. You get a much longer season of these plants you love. So use the Firestorm Rhododendron as your ‘go to’ for late in the season. It’s compact enough for the smallest garden, yet has enough impact to lighten any garden at all. Grow it in beds beneath trees in the traditional way, use it around your home, and in warmer zones, consider it as a great potted shrub that you can bring into prominence when in bloom, and move to a lower-profile spot for the rest of the year.

Hardiness

The Firestorm Rhododendron is exceptionally cold-resistant too, growing happily and without any trouble in zone 5, and certainly viable and a good choice if you are in the warmer parts of zone 4. 

Sun Exposure and Soil Conditions

Like almost all rhododendrons, your Firestorm Rhododendron will benefit frm some sun earlier in the day, followed by shade later, when the sun becomes more fierce.

The soil needs to be acidic – you can check yours with a cheap and simple meter – with a pH value below 6.5, and preferably around 5.5. The soil also needs to be moist but well-drained, so don’t plant in low-lying boggy areas prone to flooding. Enrich the soil with large amounts of lime-free material such as rotted leaves, pine needles, peat moss and lime-free garden compost. Use more of this compost as mulch each spring, applying a 2-inch layer over the whole root system, but not touching stems or foliage. 

Maintenance and Pruning

The Firestorm Rhododendron is easy to grow, as long as you have the soil, light and water correct. This plant is not drought tolerant, and needs regular watering through the summer months in particular, and during dry springs.

Deer and rabbits almost never bother it, and pests or diseases are rare if growing conditions are good. Don’t prune it, or flowering will be reduced. Should the occasional small twig die, remove it neatly. Otherwise do nothing to it. When young it is useful to dead-head the plant. This encourages the energy of the plant away from seed production and towards flowers for the following year. When all the blooms have fallen, take hold of the empty flower truss and by a twisting and snapping action you will find it detaches easily, without removing any of the foliage (which you don’t want to do. You will see new stems sprouting from the area between the base of the flower truss and the first leaves. Be careful not to damage those shoots.

History and Origin of the Firestorm Rhododendron

The hybrid rhododendron called ‘Firestorm’ was hybridized by Dr. Gustav Mehlquist of the University of Connecticut using Rhododendron ‘Vulcan’ as the seed parent and Rhododendron ‘Chocolate Soldier’ as the pollen parent. The actual variety ‘Firestorm’ was selected from among the seedlings produced from this cross.

The pollen variety has some unknown parents, but the species Rhododendron catawbiense plays a large part in its heritage. That plant is a wild species in America, growing extensively throughout the south-east on mountain slopes. Plants derived from it are highly regarded for their hardiness and excellent foliage.

The variety ‘Vulcan’ also has some unknown parents, but the dominant wild species is Rhododendron griffithianum. This is an Asian species, found across the southern mountains of the Himalayas, from Bhutan, Bengal, and Sikkim to Nepal. It is a large, hardy and vigorous plant. Crosses between only remotely connected species from very different parts of the world often show ‘hybrid vigor’ and make excellent garden plants that are hardy, reliable, long-lived and beautiful – a good all-round description off ‘Firestorm’.

Buying the Firestorm Rhododendron at the Tree Center

If red is your thing – or indeed, even if it isn’t – the Firestorm Rhododendron is a winner. The dramatic and powerful look in bloom, coming late in the season, and the overwhelming size and beauty of the blooms cannot be beaten. Yes, it may take a while to grow to a good size, but sometimes the best things come in small packages. Order now, our supply of this very popular variety is not large, and they won’t stay with us for long.