Bulbs - Iris
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  (April) I want to grow irises in my garden up here on the mountain, and a friend divided his and brought some up. They were all clumped together and some of the root system was soggy. I found a website that told me to cut those soggy roots, divide, and cut the foliage. I planted them in a nice bed of soil and humus. The rhizomes are under the soil. The irises don't seem to be faring well, though, and they get full sun. Is it the temps? Or should I replant the rhizomes partially above ground? Or should I start over, or forget growing irises up here? I know they will grow up here, though, because an old homestead is covered with them. 

  Iris rhizomes need to be planted half in the ground, and half out. They need a well drained soil, as they rot easily. Don't mulch them either. Hopefully they can still be salvaged. They can be easy to grow if they are planted properly and in a well-drained site.

  (April) Can I put the landscape material or fabric over and around my Iris? I would be putting mulch over the fabric. I know you are supposed to just put the bulbs under a very thin layer of dirt, so would this be too much on top of them? I am trying to prevent weeds and grass from taking over. 

  No, iris rhizomes don't like to be covered, so the fabric, and even mulch alone is a no-no. Because they are planted shallow and cannot be mulched, grass and weeds can be a problem, but if you mulch them the bulb can rot.

  (August) Could you tell me when to transplant iris and how deep to plant them? How much sunlight do they need to bloom well? 

  Iris can be replanted now. Be sure when digging and dividing that you leave a minimum of two fans of foliage per division. Plant them shallowly, with roughly half of the rhizome showing, and half covered up. The more sunlight the better, but a minimum of six hours is needed for bloom.

  (November)  need your advice on my Iris. The foliage is still green, with no browning in sight. If I cut the leaves off, will it deter them from blooming in the spring? I wanted to move some of them now. 

  Bearded Iris, or German Iris or flags, are typically evergreen in Arkansas. A cold winter can cause the leaves to die back, but you should still have foliage in November. We never recommend cutting it all the way off unless it does get nipped back. Most iris growers do cut the fans back by half or more eight weeks after bloom to aid in disease prevention, but even that is not necessary if you have ample space between plants. Division is usually done at the same time -- in the summer six to eight weeks following bloom. I would not recommend division as we head into winter. Although they are very hardy, iris rhizomes are planted half in the ground, and half exposed above ground. We like to get the planting done in ample time for the roots to re-establish, or they can get heaved out of the ground during the winter months. If your plants are extremely crowded, divide them in the spring as they begin new growth. It can hurt the bloom potential. Best case scenario would be to divide at the appropriate time 6-8 weeks following bloom.

  (December) Need your advise on my Iris. The leave have never turned brown-they are still green. If I cut them off, will it deter them from blooming in the spring? Also, my amaryllis bloomed this fall! Do I need to cut the foliage off it? It is in a pot. 

  Bearded iris are usually evergreen in Arkansas--we never cut the foliage off completely. If we have a severely cold winter, the foliage may get nipped back, and then you can clean up the damaged foliage. Many iris growers cut their plants back in the fall in a fan shape to make the foliage more manageable. If your amaryllis is outside, now that a frost has occurred, cut the foliage off and mulch it heavily to prevent it from freezing. I would definitely sink the pot in the ground, or bring it indoors. If it already is indoors, cut the leaves off and let it rest for several months. When you see signs of new growth beginning, then increase water and sunlight. You should have your new bloom about six weeks following the new growth. These holiday amaryllis bulbs are not considered a hardy bulb, but many gardeners have started planting them outdoors in the spring, and leaving them there. With added mulch in the fall, they have been overwintering nicely. Keep in mind that we haven't had a cold winter to test them yet.

  When is the proper time to cut the foliage off of my bearded iris? They bloomed nicely this year, and finished up about a month ago. Also, should I fertilize them any more this year? I fertilized lightly after bloom. 

  Bearded iris never need their foliage cut off completely, since they are evergreen plants in Arkansas. Many people cut the foliage into a fan shape to make the leaves fit into their landscapes more attractively, but that isn’t necessary. Any decorative pruning should be done eight weeks after bloom. One more application of fertilizer could be applied now and watered in.

  How and with what do I fertilize my iris? I separated them and reset the bed last year, but I was disappointed with the scarce number of blooms. Why does the bloom stem get so long that I have to stake them?

  Bearded iris are not heavy feeders. Too much nitrogen can cause excessive growth. Tall bearded iris can grow too tall even without excess nitrogen, depending on the growing conditions prior to bloom and also light exposure. Some varieties are more prone to this than others. Shade on one side of the plant can lead to more leaning and make them more prone to falling over. As a general rule of thumb for fertilization, fertilize with a general fertilizer in the spring as growth begins,( go light on the nitrogen if your plants are too tall already), and then use super phosphate or similar fertilizer after bloom.

  I have iris that have never bloomed. I did get a few scattered flowers when I used epsom salt on them last year. I even changed their planted area, moving them from one side of the yard to the other, so they could get more sun. What should I do now?

  Since you just moved them to a sunny area last season, give them a chance to bloom this year. If they were growing in the shade the previous season, they didn’t have enough energy to produce flower buds. Since they have been in the sun for a whole season, they should bloom for you nicely. Iris rhizomes like a sunny location with good drainage, and need to be planted shallowly with half of the rhizome exposed. The usual reasons for no blooms are too much shade, planted too deep or too crowded. Hopefully, you will have a better year this year.

  Will the iris plants we have here, grow and bloom in southern California? If so, when should they be planted?

  Bearded iris should grow well in southern California. They may benefit from a little shade in the hottest parts of the day, and will definitely need supplemental watering. The best time to move them would be in September through October. If necessary, you should get by with planting them in the spring as well.

  I have some new Iris that I planted last summer that started the new year with the leaves on several of them wrinkling in an accordion fashion, starting at the top and working its way down. Some of them have a portion of the tops of the bulb eaten away, but not all of them seem to have this damage. I threw about half of them away, those that were damaged the worst, but almost all have the folded foliage. I could throw them away if there isn't an easy solution. I dug them up last night and they are in a bucket.

  According to my contact at the Arkansas Iris society, many people have accordion-pleating on their tall bearded iris plants this spring. Frequently the new fans are trapped by the edges of the older fans and crumple and even double-back, becoming ingrown. The plants aren't sick; they're confused. It's the weather. Cooler temps followed by very hot temps followed by cool temps lead the plants to grow erratically in late winter and early spring. When the weather warms up consistently, the new-growth fans will be normal. Some cultivars are more susceptible to this pleating than others, depending upon the climates in which their ancestral species originated. Modern bearded irises are hybrids of plants that originated in desert climates, Mediterranean climates and the chilly north lands. Cultivars whose ancestors had the benefit of complete winter dormancy under a blanket of snow are really messed up by our roller-coaster winters. Carefully extricate the trapped fans or cut them free if you're in a hurry. They also mentioned that beardless irises, the Louisiana’s and their water-loving cousins, develop accordion ripples on their fans as part of their normal growth. It's a sign of excellent culture and should be a source of pride. As for insect damage: It's rampant. The aphids are out in force, and so are leaf-eating critters that are not usually seen until June. They believe these insects can spread leaf spot and bacterial soft rot, so it would be a good idea to keep a lid on them. Control the insects and keep the dead foliage cleared away to discourage infestations.

  I have planted some Japanese Irises that my mother gave me. They seem to have done quite well, the only problem is, now they are dying down. I don't know what to do with them--do you cut them down or just let them "die down". I have heard that they can be "divided" but am not sure when and how to do that. I had planted them in a bed together but believe that was a mistake, as they are very crowded.

  As perennials begin to look ugly or die back, cut the old foliage off--you don't have to wait for the foliage to completely die back. If the plants need to be moved due to overcrowding, you can also do that this fall, Plants that bloom in the summer can be divided spring or fall. Fall is ideal since they produce a stronger root system during the winter. Japanese iris normally produce huge plants, and can be tough to transplant because of a strong root system and wiry foliage. Move them to a spot where they have plenty of room to grow, so you don't have to move them anytime soon again.

  Every year we get questions regarding iris plants that were all different colors, and then something happened to cause them all to be white. This year was no exception. My pat answer has usually been it can’t happen, or it was an ‘act of God’. To make sure there wasn’t any other response, and because the calls were more frequent this year, I called on the local iris experts from the iris society. Here is their response: Over the years this topic has been discussed several times. In some parts of the country the invading iris are purple instead of white. In truth, iris can’t change colors. Different cultivars bloom at different times, with the whites being the earliest. This has also been a good year for the antique white varieties (many of which didn’t bloom well last year.) It is also possible that the sturdy antique white’s survived last summers epidemic bacterial soft rot better than some of the newer hybrids. Thank you iris folks. This isn’t the "invasion of the white iris snatchers."

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