Richard C. Bogren, Owings, Allen D.
One of the popular fall-flowering plants offered at many retail garden centers in Louisiana during late summer and early fall are cassias. Sometimes these plants are called sennas. Cassias are prolific fall bloomers and are one of the plants that are a “showstopper” in October and November landscapes. They produce a massive bloom display that attracts plenty of attention.
One of the most common of the cassias is the candlestick tree. It makes a candle-shaped bloom of golden yellow flowers. Other species also have golden yellow flowers.
Are cassias annuals or perennials? They typically survive winters in south Louisiana very well. The candlestick cassia is the one that is least likely to survive winter growing conditions.
All species have a tendency to need trimming and pruning occasionally to keep the plants manageable. Right after new growth begins in spring is a great time to remove dead wood. You also can prune slightly during the growing season to manage growth. But don’t get carried away with pruning after early summer, or you will sacrifice fall flowers.
Cassias are trouble-free and easy to grow. Plant them in full to partial sun and fertilize regularly. Cassias need minimum irrigation once established.
Seeds of all species germinate readily, but people have the most success with seed from candlestick trees. Plants also can be propagated by stem cuttings.
Cassias make a great background to herbaceous perennial borders and are highly desired by butterflies.
The LSU AgCenter and the LSU College of Agriculture