COLD HARDY PLANTS Growers and Breeders of Unusual Cold Hardy Plants

COLD HARDY PLANTS Growers and Breeders of Unusual Cold Hardy Plants

*Agave mckelveyana (Wikieup, AZ 6,500ft)*
Quantity of plants tested: 8 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 but one. 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.
	October 29, 2000 - This photo shows the first year seedlings which germinated during the second week of May 2000. Seedlings grow slow the first year and are approximately 1" in diameter.
	January 27, 2001 - here's a seedlings as of January 27, 2001. Little to no damaged was observed to date. One of eight seedlings ended up surviving the moist conditions. This one survivor was transplanted to our cactus garden in early May 2001. It has done well since.
	October 1, 2001 - here's the sole survivor as of October 1, 2001. It survived the transplant nicely. It's still very small going into it's second winter.
	October 22, 2002 - here's the same plant at the end of the 2002 growing season. Did not grow too much this year, but most Agaves are quite slow in our climate when planted in the ground as small seedlings.
	October 17, 2003 - Here's the same plant. Did it grow any this year? An Agave lophantha pup emerged next the the mckelveyana and grew larger in one season.

Home Page