Dianella caerulea Cassa Blue ['DBB03'] PP17,998 (Blue Flax Lily) - A distinctive, compact, soft blue, medium-textured, strap-leafed perennial to 18 inches tall by as wide. In later winter into spring and sometimes on to summer appear yellow-throated dark blue flowers that rise in a delicate inflorescence about 1 foot above the foliage and are followed by large lilac-blue colored fruit. Blooms a little earlier than 'King Alfred'. This is one of the slower growing more clump-forming types of Dianella that doesn't spread by wide growing rhizomes - it is also a non-cane-forming selection of Dianella caerulea, remaining as a tuft of foliage at ground level.
Plant in full sun to light shade and irrigate only occasionally to regularly. Grows well in sandy soils and reportedly tolerates heavy clay if planted on a slope or mound to insure adequate drainage. Evergreen to 24° F and is root hardy to at least 10° F. Great as an accent plant or for a mass planting where the recommended spacing is 2 to 3 feet.
Dianella caerulea is a variable species found growing wild across the eastern states of Australia and Tasmania. The genus is named after Diana, the Roman goddess, of hunting and Queen of the woods and the specific epithet means "blued" or "blue-tinged" in reference to the flower color. The genus is named after Diana, the Roman goddess, of hunting and Queen of the woods and the specific epithet means "blued" or "blue-tinged" in reference to the flower color. The variety Cassa Blue comes from Tod Layt of OzBreed Plants of New South Wales, Australia. It was first discovered in 1996 at an Australian nursery in Clarendon, New South Wales. The one known parent plant is Dianella caerulea 'Sydney Ecotype', which is a taller cane forming plant with yellow green leaf color. The breeding program involved open pollination and several other Dianella species were growing in the same location, including D. longifolia, D. revoluta and D. tasmanica. It received US Plant Patent PP17,998 in September 2007 and though this plant is listed on the patent application as a selection of Dianella caerulea, its pollen parent is thought possibly to be Dianella longifolia because of the similar color and growth habits it shares with this species.
This plant has been widely marketed as Cassa Blue but its cultivar name is 'DBB03'. Our original plants came from Celebrated Plants (VersaScapes) of Mt. Pleasant South Carolina and we were later licensed to propagate and grow it Dig Plants, Inc. We grew this plant from 207 until 2022 and only discontinued production when laboratory propagated (tissue culture) plants became difficult to source.
Information about Dianella caerulea Cassa Blue ['DBB03'] PP17,998 displayed on this page is based on our research about it conducted in our library and gathered from reliable online sources. We include observations made of this plant as it grows in our nursery gardens and in other gardens that we have visited, as well as how the crops have performed in containers in our own nursery field. We will also incorporate comments that we receive from others about this plant when we feel it adds information and particularly welcome hearing from anyone who has any additional cultural recommendations that would aid others in growing it.