Fragile (Brittle) Prickly Pear ~ Opuntia fragilis

This is a guest post by Michael Lynch - thank you Michael for your contribution!

When Heather asked me if I would be interested in writing for her blog, I couldn't think of anything sufficiently interesting. Fortunately I discovered my topic the next day I went hiking in Louisville Swamp Wildlife Refuge just southwest of Shakopee, MN. 

Fragile Prickly Pear/ Brittle Prickly Pear
 ~ Opuntia fragilis 

This is where the prickly pears grow.
The bedrock comes right to the surface and
the edges of the rock where the soil is too
thin for anything but mosses and lichen to
grow is where prickly pears do best.
Meet one of Minnesotas 3 native cactus species. (That's right, Minnesota has three kinds of cactus)
. It is a small and rather dainty cactus, but don't let that fool you, it is as tough as those spines hurt. 
It is one of the most cold hardy of the cactus species growing all the way into northern Minnesota. 

In the wild, they grow in thin soils on bedrock, or in very sandy prairies where other vegetation can't shade them out. They are called “fragile” because the slightest touch will break off the pads of this cactus and they will either stick to clothing, or the fur of bison and will hitch hike to a new spot to get established. Because they are so good at cloning themselves, they don't always flower like most other perennials. 

This is a patch of prickly pear cacti growing
on the mossy edge of the bedrock. The
background you can see the prairie, and in
the foreground you can see the edge of
the bedrock. There is only about an inch of moss
and lichen to support the cacti. 
Note the prickly
pears are reddish and shriveled for winter.

In the garden they like dry sandy soils and places where they don't have to compete with other tall plants. In their natural habitat that is provided by extremely thin soils on the edge of a rock. In the garden that means maybe the edge of a retaining wall (preferably where you don't need to weed).
A warning about the spines.

This is what Brittle prickly pear looks like in
June before it blooms. The pads are about 1-2
inches long and ¾ to an inch wide.

If you are unfamiliar with prickly pears. The spines are extremely thin, sharp and barbed. They have a habit of breaking off in your skin so you can't see them or pull them out, but make themselves known. (Ouch!)