Deno’s Garden

Rhododendron groenlandicum

Genus Rhododendron

This source reports two treatments. Both are shown.

Protocol 1

DerivedN. C. Deno, 1993

Difficulty Moderate Rated by us, not by the source.

Start around March 8, 2027 for a May 3 last frost.

  1. Gibberellic acid soak

  2. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing. Then 28 days to germinate.

63% germination in 14–28 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Ledum p. 165Public domain
Show the original text
Ledum (Ericaceae). L. groenlandicum germ. 70D GA-3(63% in 2-4 w), 700- 40-70D(23% in 4th w), and 40-70-40(none). Light had no effect.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Ledum p. 165. 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 High Rated by us, not by the source.

Start around September 10, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on September 9, 2026.

  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: dark

about 6 months from start to sowing. Then 28 days to germinate.

23% germination in 28 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Ledum p. 165Public domain
Show the original text
Ledum (Ericaceae). L. groenlandicum germ. 70D GA-3(63% in 2-4 w), 700- 40-70D(23% in 4th w), and 40-70-40(none). Light had no effect.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Ledum p. 165. 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.