Height:

3.0-4.0 Feet

Spread:

24.0-28.0 Inches

Hardiness Zones:

4,5,6,7,8,9

Flower Color:

Purple shades

Foliage Color:

Green shades

Sunlight:

Full Sun (> 6 hrs. Direct Sun) Part Shade (4-6 hrs. Direct Sun)

Water Requirements:

Consistent Water Needs

Soil Quality:

Average Soil Quality

Soil Chemistry:

Neutral Soil (pH = 7.0) Alkaline Soil (pH > 7.0)

Bloomtime:

Early Summer

Attracts Wings:

Attracts Hummingbirds Bee Friendly

Critter Resistant:

Deer Resistant Rabbit Resistant

Growth Rate:

Medium Rapid

Garden Style:

Asian Cottage Eclectic

Other Features:

Border Plant Cut Flower Mass Planting Specimen Focal Point

Origin:

Not Native to North America

Above all else, no other factor is a greater influence on Japanese Irises than water. A lack of moisture will stunt the plants and flowers, while a consistent supply of water will result in large, healthy plants with large flowers. They are lovely planted beside ponds or near streams where the water table is high, but not covering the roots. Mulch the plants heavily to ensure that the soil never dries out.

Japanese Irises should be planted in heavy, acidic, rich soil that has been amended with compost or manure. For new plantings, do not add granular fertilizer around your newly planted irises. Instead, add the fertilizer to the soil a month or two before planting the Japanese Irises. Once established, fertilize them in early spring and again right after they are finished blooming.

Most Japanese Irises require division every 3-4 years. When dividing mature clumps in spring or fall, it is best to dig up the entire clump and replant the divisions somewhere else in the garden where Japanese Irises have not been grown before. The rhizomes should be planted 2-3 inches deep. New roots form above the old roots each year, so by the time you can see the roots growing at the soil surface, it's time to divide them again.

Growing Temperature:

45-55° F

Soil PH:

6.0-7.0

EC (What is EC?):

1.0-1.5 pour through method

Fertility:

Growers can apply water-soluble fertilizers using 100 ppm of nitrogen as needed or constant liquid fertilization at 50-75 ppm nitrogen with every irrigation. Controlled-release fertilizers can also be used to deliver nutrients by incorporating 0.75-1.0 pounds of elemental nitrogen per cubic yard of growing mix prior to potting.

Pests & Diseases:

Crown and root rot (Sclerotium), leaf spot (Heterosporium,Didymellina), basil rot (Fusarium), rhizome rot (Rhizoctonia), rust (Puccinia), rhizome bacterial soft rot (Erwinia), foliar nematode (Aphelenchoides)

Potting & Timing:

Root Trimming: Rhizomes are available bare root in late summer and in 3" plug form in spring. Generally, they do not need to be trimmed.
The top 25-50% of the rhizome needs to be exposed above the soil line. This is true for the home gardener as well as the grower. Rhizomes potted up in the fall have a better chance of blooming the next season than spring planted plugs.
For bare root rhizomes: Soak in a 10% bleach solution for 15-20 minutes upon arrival. Allow rhizomes to dry in a sunny area for two to three days before planting. Overwintering losses are often attributed to overwatering; water sparingly.

Moisture:

For potting soil use well-drained commercial planting media.
Avoid excessive moisture levels during the fall and winter.

Planting Level:

The top 25-50% of the rhizome should be above the soil line.

PGRs/Pinching:

If height control is necessary, drench applications of paclobutrazol (Bonzi, Paczol or Piccolo) at 6-10 ppm will provide satisfactory results.

Lighting:

Provide high light levels.

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