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REBLOOMING IRIS
It is a great treat to look in the garden in an off-season and find majestic stalks of iris. Re-blooming iris produce more than one crop of flowers. After the Spring season, you can have nice surprises until the first hard freeze.

Rebloomers are almost as easy to grow as ordinary iris. They have the same requirements of good, well-drained soil, but do need a little extra effort. You should fertilize in Spring and again after Spring bloom. You don't want the plants to go dormant, so water them during dry weather. Also, ordinary iris can be planted under deciduous trees because they primarily need sun prior to Spring bloom; rebloomers should have at least half a day of sun all year.

Other than doubling or tripling your pleasure with re-blooms, these iris are said to be more resistant to rot, grow much more vigorously, and have less spot and insect damage. Their foliage is in better condition in July and August, in part because of the extra water and food, but also because of their genetically controlled levels of plant hormones.

Reblooming iris are available by mail from specialty growers but at least one type - 'Immortality', a vigorous white variety - can be found in more general catalogs.

Rosemary Moyers, Smith County Master Gardener
Texas AgriLife Extension


CARE OF BEARDED IRIS

If you've noticed parts of your iris plants turning soft and mushy, usually with a foul smell, bacterial soft rot (BSR) may be taking its toll. It usually appears in the spring as the weather warms. Some causes of BSR include:

  • too much water/rain
  • poor drainage
  • soil too rich
  • too much nitrogen or use of manure
  • plants are too deep
  • winter mulch not removed soon enough.
If the ground is poorly drained and remains soggy, the rhizomes stay wet. Add our Texas heat and the iris "cooks."

Problems can also be caused the nitrogen/manure application in the fall. Plants exhibit lush growth, but turn to mush in mid-spring. Go easy on fertilizer.

Too much soil over the tops of the rhizomes traps both heat and moisture. The poorer the drainage, the more important it is to keep the plants near the surface of the soil. Remove mulch from the plants early in the spring. The ability of mulch to retain heat and moisture can have the same effect as planting too deep.

Follow these steps to salvage iris afflicted with BSR:

  • lift plants, trim dried leaves and diseased foliage
  • cut or scrape rotten or mushy spots
  • place iris in solution of one part bleach to 10 parts water and stir for one minute
  • place plants in a cool, shady place to dry for a day or two
  • dust any wounds with sulfur
  • once plants are dry, replant in prepared bed.
Kathy St. Onge, Smith County Master Gardener
Texas AgriLife Extension
LOUISIANA IRIS

If you are looking for a plant that will thrive in a site with sun to partial shade and moist soil, and that features lovely flowers with interesting sword-like foliage, then Louisiana Iris is the plant for you. This tough perennial is well adapted to much of Texas, especially the acid soils and wet spring and fall condition of East Texas.

Louisiana Iris comes in a wide range of colors including blue, purple, yellow, pink, white and shades of brownish red. The flowers appear in spring on 2-3 foot stems held above the striking foliage. A single plant that is thriving in its site can form a clump 3 feet wide by 3 feet tall in two years. These clumps of green foliage add great architectural interest to the garden and will persist year round where winters are mild. They are excellent companion plants for water gardens, growing both in the water itself and on its edges.

Like most irises, Louisiana Iris likes to be planted shallow, with the tops of its rhizomes just above the soil level. They do best with frequent light feedings of compost tea, fish emulsion, or water soluble fertilizer. If not planted in moist soil, they should get extra watering.

Clumps of Louisiana Iris should be divided when they begin to produce fewer blooms. Dividing can be done in the summer, after blooming, or in early fall. Replant divided rhizomes with the top half above the soil line. Then enjoy these hardy perennials for years to come.

LuAnne Ray, Smith County Master Gardener
Texas AgriLife Extension


DIVIDING IRISES

Bearded Irises (Iris x germanica) are a favorite pass-along plant because they are easy to propagate by division. Fall is the best time to dig, divide, and replant Iris rhizomes. Just follow these four easy steps:

Step One: Working carefully around the clump with a fork or spade, dig up the rhizomes and cut the foliage back to about one-third.

Step Two: Pull the rhizomes apart or cut them apart with a sharp knife. Be sure each division has some healthy leaves attached. The smaller rhizomes on the outside of the clump are the most desirable to replant.

Step Three: To help with later identification, write the name, or color, on the leaves with a felt pen.

Step Four: Pass-along some of the Iris rhizomes to friends and plant others in shallow troughs. Do not cover the rhizomes completely with soil. Remember to water after planting.

It is usually recommended that Irises be divided every three to five years. This encourages the plant to produce an abundance of blooms.

Now, wait until spring when the Irises reward you by producing showy flowers in many beautiful colors.

Jim Powell, Smith County Master Gardener
Texas AgriLife Extension


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Gardening Tips For Northeast Texas Index