How to Divide Dwarf Iris

Step-by-Step Guide

1. 1

   Step 1: Choose the correct time to divide the rhizomes of the dwarf iris.

   Divide irises during the summer dormancy period into early fall, at least 6 weeks after the last blooms have faded.
   
   This gives the newly formed rhizomes time to become established.
   
   Irises should be divided every 3 to 4 years or when the middle of the clumps look bald.
   
   Irises may indicate they need divided when the amount of blooms decrease from year to year.
2. 2

   Step 2: Use a pair of pruning shears to cut the upper half of the leaves off the iris.

   ,, Use a garden hose to clean off the rhizomes. , The iris borer is a small caterpillar that eats its way into the leaves of the iris and then bores down to the rhizomes.
   
   The borers introduce bacteria to the rhizomes, which causes them to grow soft, turn brown, and eventually die.
   
   Use the pruning shears to cut off any rhizomes that show damage if there are several in a clump that are not infected and you wish to save them.
   
   Discard any leaves or rhizomes that have holes or are soft and mushy to the touch.
   
   Cleaning up dead iris leaves in the fall will help to eliminate iris borer eggs and reduce the number hatching in the spring.
   
   Apply dimethoate in the spring as a systemic insecticide if you have a severe iris borer problem. , You will notice that the central part of the clump, which is usually the oldest part, will have several rhizomes shooting off from it.
   
   Some may have fan-like leaves growing up from them.
   
   Use the pruning shears to cut of the young rhizomes, and discard the older, center part of the rhizome. ,,, You may store the rhizomes in a cool, dry location for several weeks before planting.
3. 3

   Step 3: Slide a garden fork under the clump of irises that need to be divided.

4. 4

   Step 4: Lever the fork up

5. 5

   Step 5: and expose the rhizomes of the iris clump.

6. 6

   Step 6: Inspect the iris rhizomes for holes that may indicate the presence of the iris borer.

7. 7

   Step 7: Look at the clump of rhizomes.

8. 8

   Step 8: Make up a 10% bleach solution by adding 9 equal parts water to 1 part bleach.

9. 9

   Step 9: Dip the blades of the pruning shears in the solution after each cut to prevent the spread of any bacteria that may be present.

10. 10

    Step 10: Replant the young rhizomes 5 to 10 inches (12.7 to 25.4 cm) apart in well-drained soil that receives plenty of sun.

Detailed Guide

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