PJM Pink Delight Rhododenron

Gardeners in colder zones look with envy on the spectacular displays of rhododendrons that are such a spring highlight in warmer areas. Sadly, they just won’t grow where the winters are severe – or most of them won’t. Don’t despair though, because there is a small group of rhododendrons that are extraordinarily hardy, and that will grow well in zones 4 and 5. These lovely evergreen bushes are so much more cold-hardy than any others, and they come in a range of colors. Our favorite is the pink-flowering form, the PJM Pink Delight Rhododendron.

The PJM Pink Delight Rhododendron is a broad, spreading evergreen bush, growing ultimately to as much as 6 feet tall, and as wide, or a little wider. It has a broad form, with many branches, each ending in a cluster of leaves. The sturdy branches are covered in straw colored bark, which sheds in strips on older limbs. The smooth oval leaves are 2½ inches long, with an attractive glossy surface. They are dark green in summer, light green when they first emerge in spring, and they take on purplish tones during the coldest parts of winter. The flowers are carried in clusters of 4 to 9 at the ends of each branch, and the large buds for the following year can be seen by late fall, already waiting. Each flower is about 2 inches long, with a flared, tubular shape. The 5 petals are fused together at the base of the flower, but separate at the outer edge, and they are a gorgeous shade of soft lilac-pink. This bright, glowing color makes a wonderful show in late April to the middle of May, depending on where you live. Flowers last for one or two weeks in bloom, and this bush, smothered in delightful color, will be a highlight of your garden in spring – even in cold places.

Grow the PJM Pink Delight Rhododendron in partial shade, or light full shade, for the best growth, and to avoid scorching the foliage in either summer or winter. It is perfect around your home, or in garden beds. It looks especially effective in a woodland setting, but it is completely at home in any style of garden. The shade close to a north-facing wall is an excellent spot, or beneath deciduous trees. Some sun in spring or fall, and in summer in cold zones, is beneficial if the soil is moist.

Not only is the PJM Pink Delight Rhododendron the only type of rhododendron reliably hardy in zone 4, it is much less demanding for acidic soils than others. It will grow well even in neutral soils, and in slightly alkaline ones too, if you add plenty of lime-free compost to the soil, and as mulch. The soil should be moist, but well-drained, so avoid areas where water stays on the ground for long periods. This plant is not drought-resistant, so water regularly if the soil around it is dry.

If your soil has a pH value over 7.5, then grow this plant in a container with lime-free compost, and you can even bury the pot directly in the ground to get a natural look. Another method is to use chelated iron, which is a special fertilizer for acid-loving plants. Apply in spring and fall, and your plant will thrive, with dark-green, healthy leaves. This plant is normally free of pests or diseases, and not eaten by deer. No pruning is needed, but if you do need to remove a stem or two, do this immediately as the flowers fade. It is a good idea, but not essential, to remove the spent flower heads. Don’t cut them, and always avoid removing any leaves with them. Instead, snap them off with your fingers directly at the base of the flowers – its easy once you get the idea, and it only takes a few minutes. You will see new shoots developing directly below the flowers – these are next year’s flowers, so don’t damage them.

The original PJM Rhododendron was developed by Edmund Mezitt in the late 1930s. He had a nursery in Massachusetts, and he used an American wild rhododendron from Carolina and Tennessee, Rhododendron carolinianum, and crossed it with a hardy plant from northern Asia, Rhododendron dauricum var. sempervirens. He tested the seedlings under cold conditions, and chose the best, which he called ‘PJM’, using his father’s initials – Peter J. Mezitt. This plant remains the hardiest of all evergreen rhododendrons and it has been unsurpassed for 80 years.

In the late 1990s Michael D Reardon, the owner of Reardon Nursery, Inc. in Boring, Oregon, bought a batch of young plants of ‘PJM’ that had been grown by tissue culture. When they began to bloom, he noticed one plant that had changed – it now had pink flowers, instead of the lavender flowers of ‘PJM’. He took this beautiful mutation and tested it, before patenting it in 2007 with the name `PJM Pink Delight`. This delightful variety is just as tough and reliable as the original, but it extends the color palette for gardener’s in cold zones. Considering how popular the original is, this plant is going to sell fast, so order now – they will be gone very soon.