Thinning and Transplanting Purple Bearded Iris

Two weeks ago the tops of my Purple Bearded Iris were cut back to about 4 inches above the ground. They were ready, I was ready...they were overcrowded and not producing flowers like they used to. Also, the rhizomes were snaking out of the ground. The root systems were so bunched up that the roots were pushing the rhizomes to the surface. So today was the day for thinning and transplanting them. One large bunch had been planted in river rocks, thus all the rocks needed to be moved first (and continuously, since many seemed to have burrowed their way into the ground). Using a garden fork, I loosened the soil around the rhizomes, then removed the clumps of rhizomes in as large a bunch as I could handle. I carefully brushed the excess dirt off of the roots so they could be inspected, and placed the rhizomes in my folding cart.

It's important that you check the iris rhizomes for root borers or for softness and throw away any that are diseased or bug damaged. Luckily all my rhizomes were healthy, and I have enough to share with neighbors and co-workers.

I kept rhizomes with leaf fans that were each in pieces about 3 - 5 inches long for replanting. Four spots in my garden were selected that had the right combination of room and light. Holes deep and wide enough for groupings of 3-5 rhizomes were dug, then the rhizomes were placed just below ground level and facing away from each other with the roots spreading out. Next came a covering of organic compost over around the roots and over all in a mound that covers the leaves. Finally the mound was watered well, and will be watered with my garden drip until first frost. They'll get some moisture throughout the winter with snow melt and some BiOWiSH™ Crop to promote good absorption of the nutrients in the compost. My Purple Bearded Iris are set for roots to re-establish themselves in preparation of a glorious springtime bloom across the expanse of my back fence. Happy Composting!