As winter approaches I am reminded of a few lessons about cold weather that I have learned (from my successes as well as failures) over my 39 years as a grower of palms and cycads. I’ll share some of these with you, in hopes that they will help you have successes with the cycads in your gardens.
Most of my difficulties in the past have centered around the damage caused by cold weather. The first 27 years of my growing experience I lived within seven or eight miles of the ocean. This was a benefit that I had little awareness of at that time. The last 12 years I have lived in north San Diego County about 14 miles from the coast, and what a difference that has made. This present location, although not totally devoid of the marine influence, is significantly warmer in the summer and much colder in the winter. In three of the past twelve winters temps have dipped to the mid teens Fahrenheit to the low 20’s for two to three nights straight. This has killed many seedling and juvenile palms and cycads. It has also burned the leaves of many of my larger palms and cycads.
The large green leaf cycads that were outdoors without any overhead canopy would often burn from the top leaves to approximately mid way down the total flush of leaves. It appears that this phenomenon is due to the descending of the cold air directly meeting the upper most leaves of the cycads. The lowermost leaves tended to be spared the direct effect of the cold air. Therefore it is clear that young cycads and palms especially benefit from overhead protection.
If you have a relatively young garden and you don’t have much overhead canopy protection, you have several possible individual or combined solutions to choose from.
- Acquire some larger plants (I prefer cold-hardy palm trees) for overhead protection.
- Use frost protection sheeting to cover plants.
- Cover cycad caudex with straw.
- Cover entire plant with an upside down grow pot or plastic trash can (only practical for smaller plants). These covers should be removed as soon as the cold passes.
- Modify or target your plant selection to species that are known to have some degree of cold tolerance.
As my garden has progressed, I have practiced all of the solutions above, however I particularly favor the use of overhead protection and have learned to try to take advantage of the symbiotic relationship between canopy and the understory plants that can benefit from it. The next newsletter will discuss possible choices for canopy plants.
Grow and prosper, Keith