Some Thoughts on Planting Elepidotes in Sunny Locations
by Marianne and Bruce Feller
-A Pitch for Early Bloomers -
Although opinion sometimes varies among growers of rhododendron with respect to the finer points of cultural requirements and preferences, we are largely of one mind when it comes to the advantage of high canopy shade for elepidotes, particularly from afternoon sun. The absence of shade, however, need not preclude elepidotes altogether.
Open exposures present a combination of challenges:
accelerated water loss
higher ambient temperatures, and
direct effects of full day sun exposure on foliage and bloom
Accordingly, your strategy for sun tolerance needs to factor in all of these issues. Assuming the availability of irrigation, water loss can be addressed directly. Use of heavy mulches will also reduce evaporation and moderate soil temperature year round.
The issue of higher ambient temperature poses a more serious challenge. Perhaps the most heat tolerant rhododendron, R. hyperythrum, is part of the solution. This species has been used in hybridizing a number of heat tolerant offspring, including R. Hypermax, R. Charles Loomis and R. Peppermint Twist. Of course, don’t overlook the obvious advantages of using lepidotes and deciduous azaleas as companion plants in open sunny settings.
Our own experience suggests that the most serious effects of direct sun on established rhododendron is largely a much abbreviated bloom period – the flowers seem to last only a day or so in hot weather before collapsing. While foliage can actually burn in periods of extreme heat and direct sun exposure, this seems less a problem than the effect of sun on the flowers.
Bearing this in mind, consider planting very early blooming elepidotes in sunny locations. April bloomers are far less likely to encounter the high temperatures that wilt flowers later in the season. You may want to try R. Taurus or R. Grace Seabrook, two excellent early reds, and/or R. Babylon, a huge early white bloom with burgundy blotch. Other early blooming elepidotes include R. Bosutch, R. Christmas Cheer, R. Jacksonii, R. Strawberry Swirl, R. Vernus and R. Spring Glory – all well suited to our Long Island climate. R. Hypermax, mentioned above, is also an early bloomer with the added advantage of R. hyperythrum parentage for basic heat tolerance.
Strengthening the case for early bloomers are a number of other advantages. Their foliage develops and matures earlier, before the strongest periods of Summer sun, and often before the host of chewing insects reach their destructive peak. They enjoy longer flower life, in sun or partial shade, and are rarely affected by petal blight.
Our obvious affection for early blooming elepidotes is also based on the fact that they are unrivaled in the garden at that time of the year – when they can be most appreciated without competing influence at the very outset of the Spring bloom period.
Plant and enjoy early bloomers!
Marianne and Bruce Feller