Mendel’s Gardens

Nasturtium officinale

Watercress

Family BrassicaceaeGenus Nasturtium

About the plant

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

Habit
Perennial, Forb/herb

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

Source: PLANTS Database — USDA NRCS.

This source reports three treatments. All are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Low Rated by us, not by the source.

Start around September 27, 2026 for a May 3 last frost.

  1. Dry storage

    Duration: 180 daysTemperature: 70°F 21°C

    Deno got the same from six months at 40.

  2. Sow and cover

    Temperature: 70°F 21°C Light: either

about 6 months from start to sowing. Then 10 days to germinate.

100% germination in 4–10 days.

Six months dry at 70 or 40, either one. A remarkable result for so aquatic a plant.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, NasturtiumPublic domain
Show the original text
Nasturtium (Brassicaceae). N. off icinale germ: best with seed DS 6 m at 70 or 40 in 70(100%in 4-10 d). Germination is less with fresh seed as shown by 70(20% in 2-27 d) and 40(81%in 3-8 w). Light had no effect. It is remarkable that a species so aquatic as this germinates best with DS seed.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Nasturtium. 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 February 8, 2027 for a May 3 last frost.

  1. Cold moist stratification

    Temperature: 40°F 4°C Light: either

No stated waiting before sowing. Then 56 days to germinate.

81% germination in 21–56 days.

If the seed is fresh, sow it cold: 81% against 20% at 70.

This source doesn't state how long.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, NasturtiumPublic domain
Show the original text
Nasturtium (Brassicaceae). N. off icinale germ: best with seed DS 6 m at 70 or 40 in 70(100%in 4-10 d). Germination is less with fresh seed as shown by 70(20% in 2-27 d) and 40(81%in 3-8 w). Light had no effect. It is remarkable that a species so aquatic as this germinates best with DS seed.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Nasturtium. 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 March 9, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: either

No stated waiting before sowing. Then 27 days to germinate.

20% germination in 2–27 days.

Fresh seed at 70 gives a fifth of what dry-stored seed gives, and unevenly.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, NasturtiumPublic domain
Show the original text
Nasturtium (Brassicaceae). N. off icinale germ: best with seed DS 6 m at 70 or 40 in 70(100%in 4-10 d). Germination is less with fresh seed as shown by 70(20% in 2-27 d) and 40(81%in 3-8 w). Light had no effect. It is remarkable that a species so aquatic as this germinates best with DS seed.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Nasturtium. 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.