Dipladenea

Dipladenia plants and container gardening go hand in hand.  Their dark green shiny foliage along with bright colourful flowers in pink, red or white make Dipladenias irresistible for both the gardener and hummingbirds, butterflies and bees. 

Dipladenias are lovers of heat.  If you put them outdoors too early in spring, they will not spring to action until temperatures reach 7 or 8 degrees C.  Provide a spot in summer’s heat and Dipladenias will thrive. 

For container gardening Dipladenias are a perfect match.  If planted in a hanging basket, you will likely need to water every day.  But if you are away for the weekend or forget to water for a day or two, Dipladenias will forgive you.  They would rather be on the dry side rather than waterlogged or consistently wet. 

Dipladenias don’t have fussy fertilizer requirements.  At planting time, they will enjoy a dose of slow-release fertilizer, repeated every two months. 

Dipladenias don’t mind being pot-bound but are easier to water and care for if roots have room to grow.  If buying a hanging basket, I recommend transplanting to a pot two inches larger than its current pot.  Use a soilless growing medium providing good drainage. 

If planted near a trellis, Dipladenias will grow vine-like, showing off its colour as it climbs upward.  Without a trellis, Dipladenias will remain shrub-like, sometimes twisting itself within the limbs of adjacent plants.  If stems reach out and become leggy, go ahead and pinch back to encourage dense growth. 

In the fall, Dipladenias can be brought indoors for winter enjoyment.  Place in a spot with plenty light and Dipladenias will do just fine.  I have a decade-old Dipladenia in a north facing window and it produces lots of lush foliage, but few flowers.  Dipladenias are sensitive to day length, and will remain dormant through winter, resuming growth again as days become longer. 

Dipladenias are often confused with Mandevillas.  The two are indeed related, but the former is actually a subspecies of the latter.  Mandevillas have bigger leaves, bigger flowers, with a greater tendency to grow vine-like.  In many respects, Dipaldenias could be considered the younger sister of Mandevillas. 

In next week’s Garden Clippings we will explore vegetable gardening in containers.