Comments on: Opuntia macrocentra, Black-spine Pricklypear

By: Andrew Block

Andrew Block — Sun, 12 Jul 2020 22:31:31 +0000

Hi Joe,

I have an Opuntia that is labeled macrocentra (var.aureispina). It is not blue. I see iNat and POWO both accept the name aureispina, but you don’t. Is that name a synonym of macrocentra or is it a valid name? Since you guys are the experts I’d like to use the correct name.

By: Joseph

Joseph — Thu, 08 Aug 2019 12:00:30 +0000

In reply to Raymond.

Hi,

The climate zones refer to the USDA plant hardiness zones.
https://planthardiness.ars.usda.gov/PHZMWeb/

You can put your zip code in and find you your zone. The zones are divided by temperature and generally report the lowest temperature you can expect in any given winter. This helps you determine what to plant. Many cacti grow in zone 8, very few grow in zone 4 where winters are cold.

Joe Shaw

By: Joseph

Joseph — Thu, 14 Mar 2019 12:00:58 +0000

Hi,
Thanks for visiting the Website. O. macrocentra is surprisingly hardy in desert or semi-desert areas. One survives at 7,000 ft in Santa Fe, New Mexico. That one has taken -10F. It grows partially under a tree and so may have gotten some protection. Normally the plant comes from the southern part of New Mexico and Texas.

Generally, desert Opuntias are not as hardy in humid/wet climates as they are in dry climates. It helps to plant them against a wall the reflects winter heat/sun. It helps them to be next to a structure that might give off some warmth. It helps them to have very good soil drainage.

Joe

By: Raymond

Raymond — Thu, 14 Mar 2019 03:49:17 +0000

What USDA climate zone?