We are in the middle of an Armageddon Winter in New Orleans. The massive temperature swings, hot then cold then hot is damaging the beauty of our lush landscapes. A few weeks ago, we experienced fridged temperatures that remained below freezing for four to six hours. These cold snaps do come with benefits that outweigh the visible damage our gardens are enduring. The benefits created by a cold snap are listed below.
The picture below is overgrown variegated shell ginger that has been severely damaged by the recent freezes. Shell Ginger is best planted suited for zone 9b to zone 10 and a good freeze helps keep the plant in shape. Once the weather begins to warm up, cut the leafy foliage all the way back to the ground.
Benefits of a Cold Snap
- Controls Insects
- Controls Disease
- Controls Overgrowth
- Controls Warm Season Weeds
In order for the benefits of colder weather to be successful, the New Orleans landscapes need the weather to cooperate. Our landscapes need the temperatures to average between 35 to 50 degrees keeping the ground temperature average 50 degrees. When the air temperature and ground temperature average is 50 degrees, the landscapes remain in a dormant growth pattern.
Benefits During Plant Dormancy
- Root Development
- Setting Flowers for Spring
- Insects Control
Record Setting Winter
In New Orleans, we typically don't have record-setting temperatures but January 17, 2018, we set a new record that has been in place since 1972 when the temperature fell to 20 degrees. In addition to the new low temperature, we experienced freezing rain, sleet, and snow. Garden beds froze, ice and snow covered tender tropicals which will lead to the death of many plants in New Orleans.
How To Determine if Plants Are Dead
Most tropical plants in New Orleans at this point are either dead or close to being dead. The tender foliage just cannot handle this extremely low temperatures. The first drop in temperatures initially burned the foliage above ground but the most recent drop in temperatures has caused root damaged. Before you remove all your plants in your garden, check to make sure the plants are dead. Use the scratch test to determine if the shrub/plant or tree is dead. First, scratch the outer layer of the bark( the cambium layer) and you will either see green under the bark or you will see brown under the bark.
Methods to the Scratch Test
- Scratch the outer layer of the bark
- Check to see if the wooden part of the plant is green or brown
- Continue checking the plant for live parts
The picture below is a agapanthus, " Lily of the Nile" that is a staple plant in so many New Orleans gardens. There is very little green above ground and with further examination, the roots already rotting below the surface.
The Winter Armageddon aftermath will play out in the coming months as the weather returns back to the typical New Orleans climate. It will be important to take the necessary steps to fix any issues with your landscape before Spring arrives.