Spuria Culture

Below is our method of planting, dividing, and caring for our spuria iris.

Soak rhizomes Step 1. Soak the rhizome in a bucket of water. If you received the rhizome dry, soak for at least 24 hours. If you received the rhizome in wet paper towels or similar, soak for about an hour. We send our rhizomes in moisture mizer solution which can be discarded.
Dig a hole Step 2. Dig a hole about two feet wide by maybe six inches deep. Reserve the soil.
Bag of Alfalfa Pellets Step 3. Get out your bag of Alfalfa Pellets.
Alfalfa Pellets Step 4. Here is a handfull of alfalfa pellets. Place all of these into the hole.
Alfalfa in hole Step 5. Add a small amount of fertilizer to the hole. An N-P-K of 10-20-20 works well.
Bag of Manure Step 6. Get out your bag of Steer Manure Compost or Blend. We get ours from a nearby local dealer. You will use lots of manure on the Spuria iris.
Manure in hole Step 7. Dump a large scoop full of your manure into the hole. Add about half of the dirt you took from the hole back into the hole. NOW, mix the alfalfa pellets, the fertilizer, the manure and the dirt well.
Fill hole with water Step 8. Fill the hole with water and allow it to drain out. Rhizomes need much moisture to become established and watering from just the top of the soil will not get water to the rhizome and roots.
Lay rhizome in hole Step 9. Set your new rhizome atop the slurry of chemicals and dirt that you created. Plant your iris in full sun.
Fill hole with dirt Step 10. Put the remaining dirt that you dug into the hole and around the new rhizome. Pat firmly. Some areas you might want to add a mulch of saw dust the first year. We do not mulch in Oregon. Water weekly and wait for growth.

Spuria can be left to grow and bloom for many years in the same area, but there may come a time you want to move or thin your clumps and share their beauty with friends. Below are what we do.

Dig rhizomes We dig our iris with a garden fork when we dig only one or two individual rhizomes. If you are digging a whole ten year old clump, expect some tough digging. Spuria are dug in the fall before signs of new growth.
Trim roots Separate the new rhizomes from the mother rhizomes. This old can be discarded if you want. Trim the roots a bit and cut back the fans to about
6 - 8 inches is good. Give yourself room to write on the fan.
label fans Make sure to label each of your fans as you dig. Don't count on your memory to know which one is which when they all look alike. Note the size of the marker laying beside the rhizomes and fans.
separate iris Note that all the individual rhizomes are labeled. Next, if replanting, soak these iris in a bucket of water for 1-2 hours and you will be ready to replant. Plant spuria iris about five feet apart, giving them plenty of room to grow. They may not bloom the first year and the second year bloom may have shorter stalks than a fully mature clump.
General Garden Care is important also. Below are a few pictures. Not included is removing the bloom stalks as soon as the bloom season is complete just as you do for bearded iris, except you might need a cutting tool to remove them. Spuria seem to set seed easily and are somewhat easy to grow from seed. Bees are strongly attracted to the sweet sap of the spuria and will pollinate the iris easily. Keep an eye open for unwanted pollination.
Bag of Lime We have very acidic soil in Oregon and Washington due to the acid rains. We often need to lay down lime to change the soil pH and reduce the growth of moss in the beds. Spuria prefer a neutral to slightly alkaline soil and they must have good drainage.
Adding Manure Spuria like manure and we use lots of it. You cannot do this to bearded irises. We apply a generous helping of manure around each clump in the early Spring when the foliage is beginning to grow and then again in the late Fall. Note the amount of manure in the photograph.
Before Cleaning Good hygiene is important with spuria just like bearded iris. Remove the bloom stalks as soon as bloom is complete for the season. Also, during the hot, dry Summer, leaves may die back. It is a good idea to remove this debris from the clumps. First year growth may die all the way back to nothing and you may think you have killed the iris, but it will begin to grow again in the fall. The photo to the left is a clump before cleaning.

It is best not to water the spuria after they become dormant. Watering sporadically can make the spuris iris vulnerable to the mustard seed fungus. There is more information about this problem below.
After Cleaning The photo to this left is a clump after cleaning. Notice the difference. In Oregon we get rain from Labor Day until the Fourth of July and often enough that we do not need to water often. It is best to water once a week if there is not sufficient rain. So if they do go dormant, do NOT water them.

Below is a photograph of our Spuria bed. It is about five years old in this picture and the clumps have grown enormously during that time. They were planted 5 feet apart and we just about cannot get around them any more. Bloom season is one to two weeks after the tall bearded iris. If your club would like some of our iris, please ask for a BUNDLE and we will supply you with a good quantity. Email us for information.

Spuria Bed

Virus affects some Spuria irises, although it is seldom very debilitating under good cultural conditions. It can cause stunting or striping of the plant and petals. The only serious desease is mustard see fungus or crown rot. Soaking rhizomes in a 5% sodium hypochlorite solution and thoroughly mixing Terrachlor into the soil before planitn are effective controls. Also, dust or spray annually in the summer for prevention. It is much easier to prevent the mustard seed fungus than to get rid of it once the iris is affected. Watering in August is an easy way for spuria to become affected with fungus, so use Terrachlor as a routine measure to prevent instead of treat for mustard seed fungus.

You can also consult the Spuria Web Site for Cultural information.