JARS v54n2 - Summer-blooming Weston Hybrids

Summer-blooming Weston Hybrids
C. J. Patterson
Norwell, Massachusetts

I don't know why more people don't grow the Weston summer-blooming azaleas in our Massachusetts Chapter. They consistently bring the highest prices of any rhododendron at our annual fundraiser auction. They consistently outperform every other group of hybrid deciduous azalea in our garden, including the Northern Lights series. They were hybridized and introduced locally, right under our collective noses, so that they are perfectly adapted to our local conditions. All of them are hardy to at least USDA Zone 5, and some to Zone 4. But still, when they come up in conversation, people will ask me, "Now, which one is that? I'm not familiar with it."

Myself, I love them. Being a "species freak," I have all of the native azaleas that I can grow, and Rhododendron viscosum is native to our little woodlot. I also grow several seed-grown samples of the species swarms that occur wherever two or more of our native species overlap in their ranges. Always I felt that some great hybridizing could be done if one only had the time. Then I discovered Weston's azaleas, and now, when I think of hybridizing, I usually begin with them!

Ed Mezitt began these hybrids using Ghent hybrids, Rhododendron viscosum , R. arborescens , and R. calendulaceum . Originally, he was striving for the broader color range of the Ghent hybrids, combined with the disease resistance and hardiness of the natives. Ed is no longer with us, but Weston Nurseries has carried forward the work, and many lovely introductions have been culled from his trial beds (it was a great help that Ed was way ahead of his time with hybridizing!).

They are called "summer-blooming" azaleas because they bloom from June through July, and into August here along the coast of Massachusetts. All of them have been selected for disease-resistance, especially mildew, and hardiness, being grown out in the open fields in Hopkinton, Massachusetts, a solid Zone 5. They are also selected for fine foliage, superior floral characteristics, and general vigor of growth. It must be remembered that these azaleas were always meant to be commercially viable plants, that could be grown in large numbers while maintaining consistent growth and habit; they are not meant to be "collector's plants" and so have no need of "sheltered locations."

The first plant of this group that I acquired showed up over a decade ago in the nursery where I worked. It was 'Pink and Sweet' and I was so impressed with the scent and great masses of flowers that I bought two and made a little pilgrimage out to Hopkinton on my next day off; the rest, as they say, was history. I now have nearly all of them, and have grown them for several years (except in the case of more recent introductions). What follows is a very personal account of this hybrid group, which in some cases differs from the official line. Taste is a very personal thing, and although I have tried to be scrupulously fair in my evaluations, I am afraid my little enthusiasms will show through.

I will start with 'Pink and Sweet', which is probably the most widely distributed of this group, having been put into tissue culture and spread about a bit. In bloom the second two weeks of June, the flowers are pink and white, with a tiny yellow flare, and very fragrant. Like all of this group, the flowers have the elongated tube and starry form of our native azaleas; the impact is a result of the sheer mass of flower. The effect is similar to that of Rhododendron viscosum with much more pink, more fragrance, and more flowers. Habit is upright, spreading with age, but still fairly compact; it will probably never get much more than 5 or 6 feet (1.5 or 2 m) tall in full sun.

Next to flower is 'Weston's Innocence', the only one of this group that I do not personally grow. It is essentially a vastly improved Rhododendron viscosum , with fine scent and billows of pristine white blossoms fit for a bride. Habit is better behaved than R. viscosum , though, with more compact growth and stronger stems.

'Western's Nectar'* is a fine hybrid that has a lovely bicolor effect when coming into bloom in late June with red buds that open to light pink flowers. It is a particularly heavy bloomer on a nice upright compact plant. The nursery says that its fragrance is light, but I find the fragrance to be particularly fine, especially on a warm late June evening. Foliage is excellent, and it even has good fall color.

'Ribbon Candy' is one of my favorites. If you look at it from a distance, you will have a great difficulty in deciding what color it actually is; when you examine the flowers close up you will see why - it has a little bit of nearly everything! The buds are dark pink, almost red, and open to pink and white striped petals with a little yellow blotch. The fragrance is wonderful, a combination of sweet and spicy, penetrating but never overpowering. I think this one will get large eventually, but shows no tendency to untidiness, even in shade as we have it. The foliage is also excellent, deep green and shiny, with good fall color, at least in sun.

'Western's Sparkler'* is a deep pink, lightly ruffled, very heavy flowering, and one of the most strongly scented of this group. It has lovely leaves, bluish green with wine-tinted fall foliage colors. This and 'Ribbon Candy' bloom at the end of June and into July, and, planted together, would form a lovely scented nook for a Fourth of July picnic.

'Millennium' blooms in early to mid-July, with long-tubed flowers of dusty red. The attraction here is the deep flower color and the great foliage. Leaves are heavy-textured and a deep blue-green, with a very upright habit. With a bit of shade, the flowers are very long-lasting, even under drought conditions, and will look great paired with Hosta sieboldii .

'Western's Popcorn'* is appropriately named, with rounded heads of sweet-scented white flowers with a yellow flare on a compact bush that seems to want to grow as wide as it is tall. Foliage is a lot like Rhododendron arborescens , slightly shiny and smooth, with burgundy tints in fall, especially in sun.

'Western's Parade' takes us into mid-July, with plentiful masses of dark pink flowers with a large orange blotch, rather like the old Ghent hybrid 'Pallas'. Unlike 'Pallas', though, it is very strongly scented. Weston Nurseries says it "gives a light sweet vanilla fragrance to the garden," but to me it is more of a sweet flowery scent; I can, however, testify to its carrying power. It seems to be strongly upright growing, with very mildew resistant leaves.

The next two hybrids are probably my two favorites of this group, and also the least grown; one seems to have sold so poorly that Weston Nurseries no longer offers it. Both light up July with flowers that are a little difficult to describe. The first is 'Golden Showers' with long golden buds dipped in bright orange-red that open to a wonderful pale gold with peachy highlights, and a golden flare. This two-toned effect is very prominent, as it takes its time opening fully. The foliage is terrific, too, glossy deep green with a bit of a twist, which sets off the fully opened pale flowers nicely. My only knock about it is that it seems to have a hard time as a young plant in making up its mind whether to grow wide or tall. Eventually, with a little age, it will bulk up and do both, but a young plant can seem rather frowzy, especially if given all the room that it will need when it grows up!

The second is 'Sandy', a hybrid that has been absent from the Weston catalogue for the last few years. My husband and I had trouble trying to remember exactly when this hybrid blooms. We have had it for several years, but it always seems to take us by surprise, blooming just when the garden is hottest and most wearisome. By putting our heads together we decided that it blooms about the same time as 'Western's Lemon Drop', and so I have placed it here, in late July. The color is medium pink with a huge golden yellow blotch covering the top half of the blossom, but the combined effect is hard to describe. If I were to say that it looks like a ray of sunshine you would think me a bit twee, but I swear it looks like the sun is shining on it even when it is cloudy. The color fairly glows, and for a long time we had to correct ourselves to visitors about its name because we kept trying to call it "Sunny." No kidding. Unfortunately, the foliage is not as good as 'Golden Showers' and the flowers are only lightly scented. The habit is only a bit less compact in part shade, and no less floriferous.

'Weston's Lemon Drop' is a very worthy addition to the group, and one that I would recommend to gardeners for mixed plantings as well as shrub borders. It has some of the finest foliage of the group, small and neat, of a wonderful glaucous blue that turns a lovely shade of pinky-red in the fall. The leaves are so distinct that it can be picked out of a group of plants in the nursery from a great distance. It was one of the earlier selections in this group, and was always very easy to sell on the strength of its foliage alone. Flowers are small but plentiful, of a pale lemony yellow, with a faint fruity scent. Habit is twiggy, compact and upright. The overall effect is a dainty and refined azalea, beautiful throughout the growing season.

'Pennsylvania'* is the latest to bloom of the summer-blooming Weston azaleas, at least officially. Long-tubed, starry pale pink flowers carry an orange blotch and a light sweet fragrance from late July into August. Foliage is good on an upright plant that will probably get to be 6 feet (2 m) with age, but is rather slow-growing.

I would like to add a few more to my list which we have not had long enough to pass full judgment on, but which seem very worthwhile. The first is 'Anna's Smile'* which bloomed for us for nearly three weeks in shade this June. The delicate flowers are a rich pink with a yellow eye and unbelievably floriferous. There were even flowers on the inside of the plant and on every short stem as well as the main stems. If it keeps this up, we will not be able to see the plant for the flowers!

Although 'Quiet Thoughts' is not considered officially a summer-blooming azalea by the nursery, I am going to include it anyway, as it does not begin blooming here until June, and its look is definitely of a piece with this group. It is another compact grower, but a bit more spreading at the top than 'Pink and Sweet'. The color is a wonderful orange-pink with a big yellow-orange blotch, which makes it a swirl of color from any distance. It is very fragrant, too. Unfortunately, it does not seem as drought-resistant as some of the others of this group.

The last hybrid I will mention is one that is not in general release yet named 'Weston's Firecracker'*. We planted it under high shade in late May and waited for it to bloom. And waited. And waited. Finally around mid-July we decided that the tight little flower buds must have been killed by the drought (we had a bad one this year) and stopped watching it. You see, because of the name, we expected it to bloom for the Fourth of July. And Lo! At the end of July, just as the drought was giving another turn to the thumbscrews, it burst into bloom! The flowers were striped red and white, with red buds, and truly earned its name. We are looking forward to seeing how this performs with age, as it is too early to tell anything about its habit or floriferousness.

As a group, these azaleas have few faults; they are all robust growers with good disease resistance, although for that I must take the nursery's word for it, as we have very little problem with disease with our dry, sunny, windy conditions along the coast. Unfortunately, they are not insect-resistant and, in fact, they actually seem more insect prone than most of our other deciduous azaleas. Along with all of the usual caterpillars and flea beetles, their worst pest is the azalea stem borer, which fortunately can be controlled by pruning the affected stems off, although this also removes next year's flower bud. I think this may be due to the very strong stems they usually have which would make them particularly attractive to this pest.

We are looking forward to watching these hybrids mature, and have begun to try them in different niches in the garden to see how they do. Some have proved relatively easy to propagate ('Pennsylvania' in particular has been easy from softwood cuttings). In general I recommend them without reservation to brighten up the long stretch from the last ironclad hybrids' bloom in early June to the first bolting of the lepidotes when the rains begin again in August!

* Name is unregistered.

C. J. Patterson is a member of the Massachusetts Chapter.