Many people have noticed the brilliant yellow flowers on roadsides over the past few weeks. While it is not surprising that many have noticed, but it is surprising how brilliant the display was and is throughout the Riverland and Mallee. Most are in fact Cassias otherwise known as Senna artemisioides subsp filifolia (syn. Cassia nemophila) “desert Cassia” and Senna artemisioides nothosubsp. sturtii (syn. Cassia sturtii) “Sturt’s desert cassia”. Wow, what a mouthful; I didn’t make up the names!
They are both shrubs form 1m to 3m and will survive in extremely dry conditions such as ours without watering and still have a regular display of bright yellow buttercup like flowers mostly in spring but will flower at other times. The Sturt’s desert cassia has broader leaves and a somewhat more golden yellow flower. Both can be breathtaking in early morning light and thanks to daylight saving, we will all see more of that! A light prune after flowering will also improve their performance in the garden.
The last two quite wet summers and a heavy rainfall event last July has meant for many deep rooted plants such as our local Cassias, there has been a moisture reserve. I am sure that this has meant that Cassias and many others are putting on an unusually good show for spring.
The message to consider for your garden is for deep rooted trees and shrubs, particularly dryland plants, deep infrequent watering is going to be far better than short shallow frequent watering.
As it warms up, we have bottlebrush to look forward to and my bet is that it will be an exceptional flowering.
So water deeply, less often and enjoy the results of better flowering plants and a cheaper water bill.
This article first published in the Riverland Weekly © October 11, 2012.