White Catawba Rhododendron

Sadly, many gardeners think that growing rhododendrons is for others, but not for them. Especially if you live in the colder parts of the northeast, you might have had bad experiences with plants browning or even dying over the winter, or suffering in summer heat, and decided to give up. While it is true that there are rhodos that need some pampering, there are plenty of others that are tough and reliable. Often dubbed ‘ironclad’, these tough, tolerant and reliable varieties should be the first choice if you are not in a ‘rhodo friendly’ part of the country. Begin with easy, reliable varieties, and once you have a core garden, then try adding something a little more demanding. Among the ironclad varieties, one of the most beautiful, and one we gladly recommend to beginners, and those with less-than-ideal garden conditions, is the White Catawba Rhododendron. A gorgeous bloomer, with buds of the softest pink that turn white as they open, it’s the perfect place to start, and you will be amazed at just how well it does. Using the White Catawba Rhododendron in Your Garden Growing to around 6 feet in 10 years, the White Catawba Rhododendron is perfect for the back of an average-sized bed in a shady part of your garden. Plant it with other acid-loving plants, like camellias and azaleas, if you are in a zone that is warm enough. Otherwise, grow it with hosta, astilbe, ferns, and other shade-lovers. Given its good tolerance of sun, especially in cooler zones, grow it too in any shrub bed – notice that sometimes the back of beds is shadier than the front, creating an ideal spot. If your soil is totally unsuitable, then consider growing it in a pot, which could be left outdoors all winter quite safely, from zone 6 upwards. In a colder area just bury the pot in the ground for the winter months, and dig it up again in spring. In a pot you can enjoy it fully when in bloom, and keep it in a less conspicuous place for the rest of the year. Growing the White Catawba Rhododendron Size and Appearance The White Catawba Rhododendron is an evergreen shrub that grows about 6 feet tall and 5 feet wide within 10 years, and will mature in time at 8 to 10 feet or even more. It has a natural rounded form, densely branched and naturally bushy, needing no trimming. The smooth leaves are just slightly glossy, and dark green. They are oval, ending in a short point, with smooth edges and a thick, leathery texture. They naturally curve downwards along the sides. Typically 2 ½ to 4 inches long, they can be 6 inches long on the most vigorous shoots. The leaves are held well through winter, suffering little or no damage, even in cold zones. The flowers form in clusters at the end of each branch, and open towards the end of spring, typically sometime during May, staying in bloom for several weeks. The clusters of blooms contain as many as 18 individual flowers, opening progressively from the bottom. The buds are flushed with a beautiful soft pink, and open to a clear, crystal-white. Long white stamens, tipped with gold, emerge from the throat, and the upper petals are decorated inside with a splash of greenish-brown spots. The overall effect is graceful, austerely beautiful, casting an almost magical light across your garden. Hardiness The White Catawba Rhododendron is exceptionally hardy, tolerating temperatures down to minus 25 degrees, and thus growing happily in the warmer half of zone 4. It grows well in almost all over zones, although it will probably find zone 9 in the southeast a bit too demanding, but not of course in the northwest. Sun Exposure and Soil Conditions As already mentioned, the White Catawba Rhododendron is quite sun tolerant, and will grow in full sun in zones 4 and 5, if the soil is moist, and is a good choice for areas with sun through the morning, followed by afternoon shade. It is very happy to grow in full shade, if it is light, and broken, such as often comes beneath open deciduous trees. The best soil is rich and moist, but well-drained, although, again, this variety is more tolerant of poorer soils than most others. It does need acidic soil, with a pH value of no more than 6.5, finding something up to 5.5 to be ideal. Use a lime-free compost to prepare the soil for planting, and as mulch. Other suitable materials included rotted leaves from most deciduous trees, shredded pine bark and needles, or peat-moss. Dig that well into the soil, creating a broad planting zone, and water thoroughly when planting, and also regularly for the first season or two. If you don’t have suitable soil, go with a pot, rather than struggling to convert your soil to be more acidic – that is usually a losing game. Choose a soil blended for acid-loving plants, and make sure your pot has a drainage hole. Water whenever the top inch or so is dry. Maintenance and Pruning The White Catawba Rhododendron needs no pruning, and is best left to develop naturally. If you must prune for some reason, do it immediately after flowering. It isn’t eaten by deer, because it is toxic, and that applies to horses and cattle too. Dogs and cats, however, almost never touch it, so it is generally safe for pets. Pests and diseases are very rare, and problems are much more likely to be the result of unsuitable soil, too much shade, or dryness. When young you can remove the spent flower heads as soon as they fade, before new shoots push out. Snap the whole head out with a quick motion, just above the topmost leaves and any new shoots. This will give you a bigger blooming the following year. History and Origin of the White Catawba Rhododendron Not all rhododendrons come from exotic locations, and here in North America we have several native species. The Catawba rhododendron, Rhododendron catawbiense, is found growing wild in the Appalachian mountains, from West Virginia into northern Alabama. Wild plants typically have violet-purple flowers. Introduced into England in 1809, it was used in early breeding with the European rhododendron, R. ponticum, to create some of the earliest hybrid varieties, notable for their improved winter hardiness. The variety called ‘Catawbiense Album’ was released by the famous breeder Anthony Waterer, at his nursery in Knap Hill, Surrey, England, in 1886. It shouldn’t be confused with other forms with similar names, such as ‘Album Elegans’, an earlier plant from Waterer, with white buds. The reason it isn’t given the more logical-seeming name of Rhododendron catawbiense ‘Album’ is chiefly because it isn’t clear that it is in fact a selection of the species, but is more likely a hybrid – we just don’t know for sure. Buying the White Catawba Rhododendron at the Tree Center If you are new to rhodos, or live in a colder zone, then the ‘ironclad’ varieties are where you should begin. Make the White Catawba Rhododendron a feature in your garden, and see how great it really is. You will soon realize why this variety, over 150 years old, is still so very popular, and always in great demand. Don’t miss this chance to plant one – you won’t be disappointed.