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Dioscorea villosa

Chinaroot · Yellow Yam · Colic Root · Wild Yam

Family DioscoreaceaeGenus Dioscorea

Two heart-shaped leaves with deep curving parallel veins, held on thin stalks above leaf litter
LeafNo machine-readable author provided. Phyzome assumed (based on copyright claims).CC BY-SA 3.0

About the plant

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

The plant

Habit
Herbaceous Perennial, VineExtension Gardener Plant Toolbox
Habit
climbing rhizomatous geophytePlants of the World Online
Flower
Gold/Yellow, Green, WhiteExtension Gardener Plant Toolbox
Blooms
Spring, SummerExtension Gardener Plant Toolbox
Native range
Canada, lower 48 states, Puerto RicoPLANTS Database
Hardiness zones
6-9Extension Gardener Plant Toolbox

Growing conditions

Sun
Full sun; Partial ShadeExtension Gardener Plant Toolbox
Soil
Loam (Silt), SandExtension Gardener Plant Toolbox
Soil pH
Alkaline (>8.0), Neutral (6.0-8.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, Moist, Occasionally DryExtension Gardener Plant Toolbox

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

Sources: Extension Gardener Plant Toolbox — NC State Extension; Plants of the World Online — Royal Botanic Gardens, Kew; PLANTS Database — USDA NRCS.

Worth knowing

  • Its names wild yam, colic root and rheumatism root reflect its use in traditional medicine. It contains diosgenin, which, despite claims, is not a phytoestrogen. Wikipedia: Dioscorea villosa

This source reports 4 treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Moderate Rated by us, not by the source.

Start around July 2, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on July 1, 2026.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C Light: either

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: either

about 9 months from start to step 3. Germination happens during step 3, in 8 days.

77% germination in 1–8 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dioscorea p. 133Public domain
Show the original text
Dioscorea (Dloscoriaceae). D. villosa germination (at 70) was benefittd by both DS and by a preliminary 3 m at 40. Germination was best using seed DS 6 m at 70 in 40-70(77% in 1-8 d). It also germ. 70(11% in- 1-3 w) for DS seed and 70(20% in 3-8 w)-40-70(37%), 40-70(44% in 2nd w), and 52% in spring in outdoor treatment using fresh seed.. Light had no effect. Seed DS 12 m at 70 germ. 70(6%)-40-70(5%) showing that DS for this long was detrimental. The seeds are thin wafers like Lilium and empty seed coats can be detected readily making seed counts accurate.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dioscorea p. 133. 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 Moderate Rated by us, not by the source.

Start around December 22, 2026 for a May 3 last frost.

  1. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C Light: either

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: either

about 3 months from start to step 2. Germination happens during step 2, in 14 days.

44% germination in 14 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dioscorea p. 133Public domain
Show the original text
Dioscorea (Dloscoriaceae). D. villosa germination (at 70) was benefittd by both DS and by a preliminary 3 m at 40. Germination was best using seed DS 6 m at 70 in 40-70(77% in 1-8 d). It also germ. 70(11% in- 1-3 w) for DS seed and 70(20% in 3-8 w)-40-70(37%), 40-70(44% in 2nd w), and 52% in spring in outdoor treatment using fresh seed.. Light had no effect. Seed DS 12 m at 70 germ. 70(6%)-40-70(5%) showing that DS for this long was detrimental. The seeds are thin wafers like Lilium and empty seed coats can be detected readily making seed counts accurate.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dioscorea p. 133. 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 3

DerivedN. C. Deno, 1993

Difficulty High Rated by us, not by the source.

Start around September 17, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 16, 2026.

  1. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: either

    20 germinated in this phase.

  2. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C Light: either

  3. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: either

about 6 months from start to step 3. Germination happens during step 3; time not stated, 21 days assumed.

37% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dioscorea p. 133Public domain
Show the original text
Dioscorea (Dloscoriaceae). D. villosa germination (at 70) was benefittd by both DS and by a preliminary 3 m at 40. Germination was best using seed DS 6 m at 70 in 40-70(77% in 1-8 d). It also germ. 70(11% in- 1-3 w) for DS seed and 70(20% in 3-8 w)-40-70(37%), 40-70(44% in 2nd w), and 52% in spring in outdoor treatment using fresh seed.. Light had no effect. Seed DS 12 m at 70 germ. 70(6%)-40-70(5%) showing that DS for this long was detrimental. The seeds are thin wafers like Lilium and empty seed coats can be detected readily making seed counts accurate.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dioscorea p. 133. 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 4

DerivedN. C. Deno, 1993

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

Start around March 21, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 20, 2026.

  1. Dry storage

    Duration: 360 daysTemperature: 70°F 21°C

  2. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: either

  3. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C Light: either

  4. Warm moist stratification

    Duration: 90 daysTemperature: 70°F 21°C Light: either

    5 germinated in this phase.

Steps after step 2 run on after germination.

about 12 months from start to step 2. Germination happens during step 2; time not stated, 21 days assumed.

6% germination.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Dioscorea p. 133Public domain
Show the original text
Dioscorea (Dloscoriaceae). D. villosa germination (at 70) was benefittd by both DS and by a preliminary 3 m at 40. Germination was best using seed DS 6 m at 70 in 40-70(77% in 1-8 d). It also germ. 70(11% in- 1-3 w) for DS seed and 70(20% in 3-8 w)-40-70(37%), 40-70(44% in 2nd w), and 52% in spring in outdoor treatment using fresh seed.. Light had no effect. Seed DS 12 m at 70 germ. 70(6%)-40-70(5%) showing that DS for this long was detrimental. The seeds are thin wafers like Lilium and empty seed coats can be detected readily making seed counts accurate.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Dioscorea p. 133. 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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