Helianthemum oelandicum

Hoary Rock Rose

Family CistaceaeGenus Helianthemum

About the plant

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

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; Wikipedia — Wikipedia contributors.

This source reports two treatments. Both are shown.

DerivedN. C. Deno, 1993

Difficulty High Rated by us, not by the source.

Start around March 12, 2027 for a May 3 last frost.

Warm moist stratification
Temperature: 70°F 21°C
Four seeds of seventeen, in 3-24 days.
Cold moist stratification
Temperature: 40°F 4°C
One more of seventeen.
Warm moist stratification
Temperature: 70°F 21°C

Germination happens during step 3, in 24 days.

24% germination in 3–24 days.

This source doesn't state how long steps 1 and 2 last.

DerivedN. C. Deno, 1993

Cold moist stratification
Temperature: 40°F 4°C
Warm moist stratification
Temperature: 70°F 21°C
The figure here is damaged in the scan.
Cold moist stratification
Temperature: 40°F 4°C
Two seeds of twenty-three in the second cold period.

Germination happens during step 3.

The first figure of this run is unreadable; the quotation has it as printed.

This source doesn't state how long steps 1, 2 and 3 last.

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