Grand Duke Arabian jasmine (Jasminum sambac "Grand Duke"), also known as "Grand Duke of Tuscany," displays large double blossoms of showy white flowers and is among the most fragrant of jasmine species. "Grand Duke" is a scrambling shrub in U.S. Department of Agriculture Plant Hardiness Zones 10 and 11. When grown in colder climates, "Grand Duke" dies back in frost and regrows from its roots. This slow-growing plant grows 6-to-10 feet tall and 3-to-5 feet wide and requires only light pruning to control size and shape.
Clean all pruning tools with a disinfectant solution, such as one part bleach to 10 parts water. This prevents the spread of disease among garden plants.
Snip off "Grand Duke" blossoms when they die, usually after about three days. Deadheading the plants prevents the flowers from going to seed, which prolongs the blooming period and helps prevent the unwanted propagation of this plant, which is considered mildly invasive in some areas.
Wait until the active growth period after the blooming period is complete before pruning "Grand Duke." Blooming usually ends in late spring to early summer.
Cut dead, diseased and broken branches back to the nearest healthy point on the plant. Cut the branches at an angle just above a healthy bud so a dead stub doesn't remain at the end of the branches.
Thin as much as one-third of the old branches to encourage new, healthy growth. Thinning out the plant opens it up to sunlight and also forces bushier growth from the cut areas.
Prune branches back to the desired height to create a more compact shrub. "Grand Duke" looks much like a cross between a shrub and a vine, so cutting the vines back makes the plant look more like a shrub specimen. This pruning technique is not required for plant health but is optional if you prefer controlled, compact plants.
Your Planting Articles
Things You Will Need
- Pruning tools
- Although "Grand Duke" is hardy in zones 10 through 11, you can successfully grow the plant outdoors in cooler climates, such as zones 8 and 9. Outside of its preferred zones, however, the shrub dies to the ground in winter and grows from its roots in spring, making it unlikely that the plant will ever reach a mature size of 10 feet.
- jasmine image by Przemyslaw Koroza from Fotolia.com