Growers and Breeders of Unusual Cold Hardy Plants
Agave neomexicana (Caballo Mts., Sierra Co., NM)
Size of plant tested: 1st year seedlings which germinated May 2000.
Soil texture: sandy loam
When planted: the seedlings were planted in soil in June 2000.
Winter protection: no mulch of any kind, glass covered top of seedlings from early November through March 2001.
Microclimate: cold microclimate, 100% shaded from November through end of February.
Temperature: refer to 2000-2001 winter on this chart
Findings: all the plants died. All did well until February when the soil surface thawed but the lower soil remained frozen. The lower frozen layer prevented the excess moisture at the surface from draining, therefore, the seedlings were sitting in water for several days. There were many days when the top 1/2" to 1" of soil was thawed, but the lower soils were still frozen. Freeze/thaw cycles may have also played a role in their death since water expands 10% when frozen. Low temperature was not observed to be the cause of death, this years low was 4F.
