Cactus Graft Update

Two months ago, I grafted some small cactus onto Opuntia pads.  One of the grafts has taken while the other is slowly failing.

The Successful Graft

The successful graft still has a good seal between the rootstock and the scion.  The successful graft has grown, although slower than I would have liked.  The scion’s ungrafted peers from the same batch are now mostly larger than the grafted scion.  I don’t know the scion species, and it may be a different species from the rest of the seedlings from the same nursery.  The scion’s nursery was from a bag of “mixed seeds”, so I may be unlucky with my selection of scions.

successful

The Questionable Graft

The unsuccessful graft had some early problems.  Because the rubber bands were too tight, I knocked the scion off the morning after I made the initial graft.  The callus had not fully formed, so I reattached the graft.  The tight rubber bands also bent the rootstock.  As time went by, the rootstock corrected its bend, however one side of the scion peeled off the rootstock.  The scion pushed roots down between the scion and the rootstock.  You can see the roots in the photo (red arrow).  The side of the scion with the roots pressing down shriveled.  I believe the other side of the scion is still attached to the rootstock, so I am leaving it be for the time being.  The successful graft is now considerably larger than the questionable graft.

unsuccessful

Cactus Graft

This past winter, I found a bag of “mixed cactus” seeds from 2009 – the kind you find in the seed bin at Lowes next to seasonal tomato and pepper seeds.  Growing cactus from seed takes very specific growing conditions, so I don’t think most of these packets actually turn into plants.  But I wanted to give it a shot, so I planted them in February.  I ended up with around 40 small cactus.  Most cactus grow very slowly, and while my tomatoes planted at the same time are 5 feet tall sprawling vines, my largest cactus are marbles.

Prickly pear cactus proliferate in my city, and unlike my “mixed cactus” variety, our local Opuntia grow with gusto.  Cactus growth rates are largely determined by the growth profile of the rootstock, so I’ve been thinking of grafting some slower-growing cactus to an Opuntia.

I went for a walk in my neighborhood, and saw a badly damaged Opuntia.  The cactus, which was between the sidewalk and the curb, looked like it had been partially weed-whacked and had some household garbage thrown on top.  I found a pad which was severed fairly cleanly sitting on the ground, so I picked it up and took it home for a Frankensteinian experiment.

Step 1:  Gather your materials.

Cactus Cutting Materials

I used:

  • Scion nursery
  • Rootstock
  • Cutting board cleaned in dishwasher
  • Sharp knife for cutting
  • A spoon for digging the scions out of their nursery
  • Rubber bands for securing the graft

Step 2:  Cut your cactus

I removed the scions from the nursery and set them aside.Cactus Scions Before Cut

This is what the rootstock looked like before cutting.
Rootstock Before Cut

You will need to cut both your rootstock and your scions.  I started with the rootstock.  You can get two bases from one Opuntia pad.  I cut the pad in five pieces.  The two small pieces on the side are discarded.  I cut these bits off because the cuts will curl in, and I don’t want much excess flesh to push my scion off the top of the graft.  I stuck the very top piece into some soil.  It may or may not survive, but it’s of low priority for me.

Rootstock After Cut

I cut the scions into roots and tops.  I planted the roots, but I doubt they will survive.

Cactus Scions After Cut

Step 3:  Secure the graft

Each scion gets stuck to one rootstock.  I secured mine with rubber bands.  The blue rubber band was properly sized and attached securely.  I had some issues with the red rubber band.  24 hours after the graft, the rubber band started moving under the graft.  When I removed the rubber band to resecure the graft, the scion fell off.  I reattached the graft, but I am unsure if this is going to ruin the graft.
Graft healing

Step 4:  Wait

I placed my grafts in my bathroom where they would not be exposed to bright light or heat.  I waited two and a half weeks before removing the rubber bands.  I started noticing roots growing from the bottom of the rootstocks, so I figured it was time to plant them.

Step 5:  Plant

I removed the rubber bands and stuck the grafts into some cactus soil.  I am keeping the pot inside for another week before taking it outside to face the August heat and sun.  I am confident the graft from the blue rubber band was successful.  The red rubber band graft looks fine except being bent over, but I am not as confident the two cactus actually joined.

Graft Planted