Snapdragon relatives like diascia and nemesia still seem to be unfamiliar names even though they have been around for 15 or more years. It seems gardeners are willing to grow snaps but still aren’t sure about the smaller cousins. The sundiascia series however should give everyone a swift kick to get it in the ground.
The sundiascia was recognized at the Chelsea Flower Show, which puts it among some outstanding company. It turns out this trouper is not only more heat tolerant than most diascias but is also cold hardy to 5 degrees. This should make it a winner everywhere.
The sundiascia series has 6 colors and they grow upright to 15 inches with an outward spread of 18 to 20 inches. They come in blush white, bright pink, peach, blush pink, orange and rose. I’ve grown diascias for several years and this habit is very striking in both the landscape and containers.
I am still a fan of Blue Bird nemesia. Not only is it one of the oldest in the market it is also still easy to find. It possesses a moderate amount of frost tolerance and has been surprising in handling warm temperatures too.
The sundiascia series has 6 colors and they grow upright to 15 inches with an outward spread of 18 to 20 inches.
For tantalizing fragrance I’m partial to the Sachet series, all colors. They have the ability to thrill with the olfactory experience, making you want them in containers close to the front porch or patio. They get 12 to 14 inches tall and produce loads of tiny snapdragon-like flowers.
Both diascia and nemesia will reward soil preparation if growing in the landscape. Apply 4 to 6 inches of compost or peat and incorporate into your soils. Full-sun, fertile, well-drained soil and light monthly applications of a slow-release fertilizer with minor nutrients are all that is needed. The sundiascia is self-cleaning but light pruning and deadheading on the Bluebird nemesia will keep it bushy and more attractive.
Norman Winter is director of the Coastal Georgia Botanical Gardens at the Historic Bamboo Farm, University of Georgia Cooperative Extension, and author of “Tough-as-Nails Flowers for the South.”