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Iris lactea

White-flower Chinese Iris

Family IridaceaeGenus Iris

A violet iris with cream falls veined purple, flowering low in coarse grass
FlowerImartin6CC BY-SA 3.0

About the plant

What it is and where it grows — not part of any germination protocol.

Habit
rhizomatous geophytePlants of the World Online
Flower
Pale violet, milky white, yellowFlora of China
Native range
Afghanistan, Altay, Buryatiya, China North-Central, China South-Central, China Southeast and elsewhereGBIF Backbone Taxonomy

Toxicity is noted only where a source states it. No note here is not a finding of safety.

Sources: Plants of the World Online — Royal Botanic Gardens, Kew; Flora of China — Wu Zhengyi, Peter H. Raven and Hong Deyuan (eds.); GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Worth knowing

  • Its name means milky color, hence milky iris. One of the commonest wild irises in China, its leaves are used for fodder, thatching, matting, basketwork, paper and brushes, and it has been planted en masse to reduce lead in contaminated soil. Wikipedia: Iris lactea

This source reports two treatments. Both are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty High Rated by us, not by the source.

Start around September 22, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 21, 2025.

  1. Clean the flesh off the seed

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    6 germinated in this phase.

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  4. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    19 germinated in this phase.

  5. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  6. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  7. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  8. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  9. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  10. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    8 germinated in this phase.

Steps after step 8 run on after germination.

about 18 months from start to step 8. Germination happens during step 8; time not stated, 21 days assumed.

21% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Iris p. 156Public domain
Show the original text
Iris (Iridaceae). This genus gave -not only great diversity in germination behavior but also some of the most extended multicycle germination observed. Germination is always hypogeal, and true leaves develop in 'a week or two once the radicle emerges even when germination was delayed for years. Empty seed coats and deformed seeds are relatively easy to recognize so that seed counts and percent germination are accurate. A major problem is how to stimulate the germination of Oncocyclus and Regelia Iris since they have such extended natural germinations. Panayoti Kelaidis of the Denver Botanical Garden has iritorrmed me that Fritz Kummert In Austria, Frank Norris in Tennessee (USA), and David Shahak in Israel are growing Oncocyclus Iris from seed in large numbers. Panayoti said that there are reports that germination was much improved by rinsing the seed in dilute Chlorox (aqueous NaOCI) and rubbing off the seed coats after which the seeds germ. readily at 40. There are also reports that gibberelic acid and other chemicals stimulate germination. Data is needed using scientific procedures. A recent book, "The Iris" by B. Mathew, is devoted to this genus. Mathew divides the genus into six subgenera with further division into sections and series. His arrangement is used only in part. The species are arranged in alphabetical order for convenience with subgenus or section indicated in parentheses using the abbreviations B (bearded), Bx (beardless), E (Evansia), 'N (Nepalensis), .0 (Oncocyclus), P (Pardanthopsis), A (Regelia), At (Aeticulata), and X (Xiphium). I. lactea (Bx) germ. best in outdoor treatment. Unfortunately this was tried only on seed that had been DS for 2 y at 70 and had been soaked for 7 d and 4 w. Both samples germ. 90% in March and April from sowing in November. It can only be presumed that fresh seed would have given similar behavior and that the soaking and WC treatment is probably not necessary. Germination is much extended in other treatments as shown by 70(6%)-40-70(19%)-40-70-40-70(21%)-40-70(8%) and 40- 70(9%)-40-70(3%)-40-70(6%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Iris p. 156. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

Protocol 2

DerivedN. C. Deno, 1993

Difficulty Very high Rated by us, not by the source.

Start around December 15, 2026 for a May 3 last frost.

  1. Clean the flesh off the seed

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

  4. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  5. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    3 germinated in this phase.

  6. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  7. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C

    6 germinated in this phase.

Steps after step 3 run on after germination.

about 3 months from start to step 3. Germination happens during step 3; time not stated, 21 days assumed.

9% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Iris p. 156Public domain
Show the original text
Iris (Iridaceae). This genus gave -not only great diversity in germination behavior but also some of the most extended multicycle germination observed. Germination is always hypogeal, and true leaves develop in 'a week or two once the radicle emerges even when germination was delayed for years. Empty seed coats and deformed seeds are relatively easy to recognize so that seed counts and percent germination are accurate. A major problem is how to stimulate the germination of Oncocyclus and Regelia Iris since they have such extended natural germinations. Panayoti Kelaidis of the Denver Botanical Garden has iritorrmed me that Fritz Kummert In Austria, Frank Norris in Tennessee (USA), and David Shahak in Israel are growing Oncocyclus Iris from seed in large numbers. Panayoti said that there are reports that germination was much improved by rinsing the seed in dilute Chlorox (aqueous NaOCI) and rubbing off the seed coats after which the seeds germ. readily at 40. There are also reports that gibberelic acid and other chemicals stimulate germination. Data is needed using scientific procedures. A recent book, "The Iris" by B. Mathew, is devoted to this genus. Mathew divides the genus into six subgenera with further division into sections and series. His arrangement is used only in part. The species are arranged in alphabetical order for convenience with subgenus or section indicated in parentheses using the abbreviations B (bearded), Bx (beardless), E (Evansia), 'N (Nepalensis), .0 (Oncocyclus), P (Pardanthopsis), A (Regelia), At (Aeticulata), and X (Xiphium). I. lactea (Bx) germ. best in outdoor treatment. Unfortunately this was tried only on seed that had been DS for 2 y at 70 and had been soaked for 7 d and 4 w. Both samples germ. 90% in March and April from sowing in November. It can only be presumed that fresh seed would have given similar behavior and that the soaking and WC treatment is probably not necessary. Germination is much extended in other treatments as shown by 70(6%)-40-70(19%)-40-70-40-70(21%)-40-70(8%) and 40- 70(9%)-40-70(3%)-40-70(6%).
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Iris p. 156. Quoted exactly. Every value on this card comes from this record, except the difficulty rating, which is ours; the step names come from a fixed list.

How each step is done, in Deno’s words, and what Verified and Derived mean.

Germination trials

Readers’ own records of sowing this species, published after review. Share your trial · All trials

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