My elderly client has ever-encroaching prickly pear cactus in her southern NJ yard (it's everywhere down here); the thorns are injurious, she has mowed it down to grass level, and she can't dig it all out. Are there any other species of plant that will trump this stuff and squeeze it out? She's not going to dig, roundup, eat, grill, distill or do anything else with the cactus. She would however, be willing to hugleculture the worst areas if she was sure it wouldn't come through the bed. Are goats or other livestock an option as well? All thoughts are appreciated.
I think she really wants something growing right away - I suggested sheet mulch but she declined (wasn't sure if it was the cost, effort or what making it a non-alternative). If the stuff definitely can be smothered via soil and other plantings, that seems to be most attractive to her. I just don't know how invasive/resilient prickly pear is. Like English ivy? Like mint? I have no idea.
I would try a heavy cardboard sheetmulch then, with immediate planting through it....preferably not immediately on top of the old cactus crowns. Another idea would be to mow it and then plant something there requiring, and benefitting from, continuous and heavy irrigation. I doubt the prickly pear would appreciate that. What about a grass/clover/etc. cover crop, watered and regularly mown; which would wear out the cactus anyway?
If it's the native species, it isn't invasive. (natives belong, so they can't invade).
Mowing isn't always effective for Opuntia, since, depending on conditions, the cut up pieces are quite capable of rooting and growing more plants. Also anything that doesn't actually remove the plants physically runs the risk of leaving spines in place to get you down the road sometime..
Hugelkultur would work- they will not grow up through a thick layer of wood and soil- as long as you will never be sticking your hands into the layers that have the cacti (see previous note!)
The plants grow from seed as well as rooted pieces, but neither way is fast to establish- if you dig up all the pieces they can't grow back any time soon, it will not come back from roots, and seeds take years to reach any size.
Definitely if you could waterlog the area, cacti do not like prolonged wet, but you'd still need to get rid of the spiney corpses.. The only thing I can think of getting rid of the plant entirely without digging might be a long hot fire..
Why not advertise for local cactus lovers to come rescue them? Many people treasure their native cacti and have beautiful gardens built around the locals and many other species.
edge of the boreal mixed woods zone, just east of the Rocky Mtn Foothills, z 2/3
I like you because you always keep good, crunchy cereal in your pantry. This tiny ad agrees: