Spring is always a highlight time in the garden, and in all but the coldest areas rhododendrons and azaleas are a big part of that season. Nothing else has such spectacular blooming, or such rich, vibrant colors. In warmer areas evergreen azaleas are hugely popular, and they bloom in a myriad of colors in many gardens. But after the season has ended, they are, honestly, a bit boring, and become ‘plain-Jane’ green bushes for the rest of the year.
At least, that’s how it has always been. In the last few years all that has changed, with breeders creating new plants that are reblooming. That is, after their first spring blooming, they produce more flowers, typically in late summer and fall. Because of these breakthroughs, now azaleas really earn their place in the garden, with months instead of weeks of blooming, particularly valuable because of the relatively small number of bushes that bloom later in the season.
At the Tree Center we work hard to keep up with the best, and so we have a big range of reblooming azaleas, including the range called ReBLOOM™, which we recommend particularly for zone 6, and anywhere you want to grow azaleas in partial shade, rather than in full sun. Available in a range of colors, and with bushes that grow to different sizes, the ReBLOOM™ Azaleas are a fabulous new variety that our customers love – and so will you.
The ReBLOOM Azaleas are evergreen shrubs, varying in size between 1 and 3 feet tall, with a spread of 2 to 4 feet, depending on the particular varieties you choose. This range of sizes means they can be used in numerous ways, fitting into different sized gardens and beds, either in the foreground or middle parts. They have a dense, twiggy structure, with foliage all the way to the ground. The small leaves are oval to elliptical in shape, around 2 inches long and an inch wide. They have a good substance, and their dark, rich green coloring means they give excellent structure to the garden. The leaves are soft to the touch and covered with a coating of fine hairs. A few leaves may fall in winter, especially in zone 6, but they remain substantially evergreen, so they look attractive all year round. The growth rate of the ReBLOOM Azaleas is rapid, and they add 8 to 12 inches of new growth each year, if you care for them. This means that they will be effectively full-grown in just a few years.
Of course, it is the blooms we grow flowering shrubs for, and the flowers of the ReBLOOM Azaleas really are wonderful. They are funnel-shaped, made up of 5 partially-fused petals, and they are 3 or 4 inches across, again depending on the particular variety you are growing. Some have a classic single flower, that is, one with a simple funnel, with fluted edges, and often with attractive streaks, flecks and spots marking the inside of the funnel. Other varieties have semi-double or double flowers, which have extra swirls of petals inside them, making a full flower, with a more rounded look. With their frilly edges and twirls of smaller petals at their heart, the blooms are the very picture of elegance and charm.
The flowers of the ReBLOOM Azaleas are carried in clusters of several blooms at the ends of each stem, and with that dense twiggy structure to the bush, this means the plant is smothered in blooms, so much so that the leaves hardly show at all. As for color, the range of varieties covers the spectrum from pure white to rich orange-reds, with many shades of pink in between.
The great thing about the ReBLOOM Azaleas is that they are not limited to one flowering season. There is a full blooming in spring, along with the old-fashioned varieties. Because the buds open over a week or two, the spring season is long, lasting for several weeks, and making a great display at that important time of year. After the last blossoms fall there is a short period without blooms, but by late July blossoms are starting to appear again, and soon there will be a continuous display right through the fall, ending only when the temperatures fall and the remaining buds begin to rest until the following spring. This transforms azaleas from spring-blooming plants into valuable summer and fall blooming plants too.
With their repeat blooming, the ReBLOOM Azaleas have so much to offer in your garden. They can be used as single plants in smaller beds, or in group planting in larger ones. They are neat and compact enough to use around your home, in the foundation planting. They fit into all styles of garden, from formal arrangements to Japanese-style gardens – the Japanese love azaleas – and in natural woodland settings too. With their wide range of colors, they fit right into any color scheme, and they are truly adaptable. With a choice of sizes among the different varieties, that are low-growing and medium-sized, they can be used for both edging and planting in the middle part of beds, and the smaller varieties are ideal for edging pathways or beds.
For containers and planter boxes too, the ReBLOOM Azaleas are perfect choices. For planters you want shrubs that deliver a lot of color over the years, and with their repeat blooming they certainly fill that need. Their evergreen foliage makes a perfect background for other plants, and keep your boxes looking full during the weeks they are not in bloom. Growing in boxes is also perfect if you don’t have the necessary acidic soil for them, as you can simply use appropriate potting soils.
One of the most helpful features of the ReBLOOM Azaleas is their winter hardiness. They are all completely hardy in zone 6, taking winter lows of minus 10 degrees Fahrenheit without any problems. They won’t shed their leaves, burn or shrivel either. There are other azaleas that are hardy in zone 6 of course, but among the reblooming types there are few that are reliable in zone 6. At the other end, these plants thrive in zones 8 and 9, where of course they will bloom early, and rebloom for a very long time in the fall.
The most common other rebloom azaleas are the Encore® Azaleas, and these plants are similar in many ways to each other. They do have some important differences in growing, which may determine which ones you grow, and where you plant them.
Hardiness – although some of the Encore Azaleas will grow in sheltered spots in zone 6, with some extra care, zone 7 is the safest ‘cut-off’ for them. ReBLOOM Azaleas were bred to be completely hardy throughout zone 6, and they are.
Sun or Shade? – because of the parentage of the Encore Azaleas, they grow best, and rebloom most reliably, when grown in full sun, or with just a little shade for a few hours of the day. The ReBLOOM Azaleas are much better adapted to shade, and outside of zone 6 they need at least afternoon shade, or full light shade. In most gardens you will have spots with all sorts of shade conditions, so you can choose the type that is best for the spot you are planting.
Size – some of the ReBLOOM Azaleas spread up to 4 feet wide, which is more than any Encore Azaleas. For larger areas this could be something to consider too.
The ReBLOOM Azaleas are not at all difficult to grow, but they do have some basic requirements. Once these are satisfied the plants largely take care of themselves.
The Ideal position for a ReBLOOM Azalea depends on your zone. In zone 6 they will grow in full sun, if the soil is reliably moist. In other zones some shade is best. In most zones they will even grow in full shade, if it is the shadow from a wall, or light shade from overhead deciduous trees. In general, they grow well in partial shade, and locations with morning sun and afternoon shade are ideal.
The ideal soil will be moist but well-drained, and richer, loam soils are better than dryer sands or heavy, wet clays. The soil for your ReBLOOM Azaleas needs to be acidic, with a pH of 6.0 or less. If you or your neighbors are already successfully growing azaleas, rhododendrons or camellias, without the new leaves being yellow, then you will have no problems. If you don’t know the pH of your soil, there are simple test kits available at any hardware or garden store. If you have a pH between 6.0 and 7.0, you can probably grow them successfully with suitable fertilizers and treatments, but the simplest solution of your soil is not acidic enough is to switch to container growing.
The place you are going to plant in should be prepared by digging plenty of lime-free organic material into it. Garden compost, rotted leaves and peat-moss are all suitable. Dig a broad hole and mix up the soil at least 8 inches deep, and over a 2-foot wide area. Plant at the same depth as your ReBLOOM Azaleas are in their pots, and water well while planting. Water twice a week for the first month, and then weekly after that until they are well-established.
For group plantings, space the plants about three-quarters of their spread apart. For example, if your chosen variety has a spread of 36 inches, then space 24 to 30 inches apart. Don’t plant groups in neat rows, and instead scatter them over the area you want to cover, except when you are creating an edging for a bed. For smaller groups, use odd-numbers – 3 or 5 make a better-looking group than 4 plants will.
If your soil is not acidic, or if you want plants for a balcony or terrace, then grow the ReBLOOM Azaleas in planter boxes or pots. These should have good drainage holes, and they don’t need to be very large, as azaleas have fibrous root systems, and take well to long-term pot growing. The best pots will be wide and shallow, not narrow and deep, as the roots are mostly close to the surface. Use potting soils blended for acid-loving plants, and container plants should be fertilized regularly for the best results. Use fertilizer blends for azaleas or for any acid-loving plant, and liquid formulations work best for planters.
Water container plants regularly, whenever the top ½ inch has dried. Always water thoroughly, so that a little water flows through the drainage holes. Don’t leave plants standing in a saucer of water.
Mulch is always a good plan when growing ReBLOOM Azaleas in the garden. Use lime-free organic materials, covering the root zone a little beyond the spread of the branches, and keeping the material clear of stems and foliage. A layer about 2 inches deep is ideal.
ReBLOOM Azaleas are not drought-tolerant, so water regularly during drier periods, watering thoroughly over a wide area, to encourage the roots to grow outwards.
A fertilizer program will give the best results outdoors, and liquid or granular formulations are both suitable. Follow the directions – normally feeding in early spring and mid-summer will give the best results. Consider using slow-release formulations so that you only need to feed once a year. Either chemical or organic fertilizers will give good results.
With their naturally dense, twiggy growth, trimming and pruning is rarely needed for the ReBLOOM Azaleas. If you do want to trim, do this immediately after the main spring blooming is over. Pruning at other times will reduce flowering. Light, regular shaping once a year is preferable to hard pruning, which is rarely needed anyway.
Robert Head is a professional azalea grower in Seneca, North Carolina. Back in the 1990s he gathered together a large collection of existing azaleas that had some tendency to produce a few flowers in fall. He cross-pollinated them in many different combinations, and then grew 80,000 seedlings from his crosses. He studied them carefully over several years, and then he selected 200 plants that were showing lots of reblooming. From those he selected his final 9, looking for good structure, beautiful colors, well-formed blossoms, and of course maximum reblooming. He was especially interested in hardiness, and all his plants were thoroughly tested, and proved reliable, in zone 6.
Available in a wide range of colors, and in different sizes, there are sure to be varieties of reBLOOM azaleas that fit perfectly into your garden. Let’s take a look:
|Blush Elegance||18 – 24||30 – 36||Large pink flowers, low and broad|
|Cherry Pink Prestige||12 – 18||24 – 30||Rich pink flowers, low growing|
|Coral Amazement||24 – 30||30 – 36||Rich coral-red flowers|
|Firebrick Fame||24 – 36||30 – 36||Red-orange double flowers, rounded bush|
|Pink Adoration||18 – 24
|24 – 36||Large, warm-pink flowers|
|Red Magnificence||24 – 36
|36 – 48||Bright red flowers, larger bush|
|White Nobility||30 – 36||36 – 48||Pure white flowers, larger bush|
The ReBLOOM Azaleas are a major breakthrough in azalea reblooming, turning spring plants into summer and fall bloomers. You won’t believe it until you try them, so start growing these fabulous plants in your garden – you will be amazed.