Hibiscus – White Pillar® – Rose of Sharon – Hibiscus syriacus
The technical term for plants that grow tall and narrow like the Pillar series of rose of Sharon is "fastigiate" (pronounced fa-stidge-itt).
Rose of Sharon requires essentially no special care. A good 2-3" layer of shredded bark mulch would be a welcome addition to the root zone. Pruning is rarely required but can be done in early spring. If you wish to fertilize, a granular fertilizer formulated for woody plants, like a rose fertilizer, can be applied in early spring, once the ground has thawed.
Rose of Sharon can be quite late to leaf out in spring, so do be patient.
The only limit to the uses of the versatile, unique rose of Sharon is your imagination! We do recommend it get a minimum of six hours of bright sun for best looks and performance.
Maintenance Category Easy
Water Category Average
Blooms On New Wood
Flower Form Border Plant, Container, Good for Screening, Landscape, Mass Planting, Specimen or Focal Point
pH C - pH 6.0 - 6.5
EC (2:1 Extraction Method) 1 - 1.5
Fertilization 100 - 200
Light Requirements High
Water Requirements Moderate to Moist
Rooting Out Temperature 65 - 72° Fahrenheit
Growing On Temperature 70 - 75° Fahrenheit
Holding Temperature 65 - 72° Fahrenheit
Planting and Timing Information
Plant in spring for Summer Finish. 1 ppp.
Pinching and Growth Regulators
With liner grown plants, to encourage branching, soft pinch when the shoots are 2-3 inches long leaving 4-6 leaves on each branch. Allow at least 6 weeks from pinching until the desired bloom date. If using liners in larger pot sizes, additional pinches may be necessary.
With bare root grown plants, pinch when new growth is 4-8 inches tall, leaving 4 to 6 leaves below the pinch. Allow at least 6 weeks from pinching until the desired bloom date.
Plants grown outdoors should not need growth regulator applications.
When grown in greenhouses, spray multiple applications of the tank mixture of B-Nine at 3750 ppm and Cycocel at 1000 ppm or Sumagic alone at 7.5 ppm.
It is best to begin PGR applications about 3-5 days following a pinch and apply them at 7 day intervals, if additional control is necessary.
Pest and Disease Management
Standard pest and disease practices as stated in the notes.
Aphids, spider mites and whiteflies may be problematic, scout and treat as necessary.
-Plant the crown (where the roots meet the stem) just below the media surface. Bare root plants will have woody stems that can be several inches long, these will be above the ground.
-These are heat loving plants and they can be grown up to 80 degrees, just be sure the plants do not dry out.
-High light produces better branching, more flowers per plant and shorter plants.
-Never allow the plants to wilt or lower leaf yellowing, bud abortion and lower quality will result.
-These are vigorous plants and proper plant spacing is necessary for high quality plants, do not overcrowd.
-Summer Storm is a dark foliaged plant, however, the foliage color only develops with direct sunlight.
-Bare root plants can usually be potted and grown directly outdoors in late spring. Protect the plants from extreme cold as needed.
-Bare root plants should be used only in 2 and 3 gallon containers.
-Liners can be grown in gallon or larger containers. If using liners in 3 gallon containers you may want to use 2 to 3 liners.
-In climates with very mild winters, plants may be very late to emerge from dormancy.