Deno’s GardenMy Garden

Veronicastrum virginicum

Blackroot · Bowman's-root · Culver's Root

Family PlantaginaceaeGenus Veronicastrum

Tall tapering white flower spikes crowded with tiny florets, above whorls of narrow dark leaves, against a clipped hedge.
FlowerAcabashiCC BY-SA 4.0

About the plant

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

The plant

Habit
Herbaceous Perennial, WildflowerExtension Gardener Plant Toolbox
Habit
perennialPlants of the World Online
Height
4-7 ft1.2-2.1 mExtension Gardener Plant Toolbox
Spread
2-4 ft0.6-1.2 mExtension Gardener Plant Toolbox
Flower
Blue, Pink, Purple/Lavender, WhiteExtension Gardener Plant Toolbox
Blooms
Spring, SummerExtension Gardener Plant Toolbox
Native range
Canada, lower 48 statesPLANTS Database
Hardiness zones
3-8Extension Gardener Plant Toolbox

Growing conditions

Sun
Full sunExtension Gardener Plant Toolbox
Soil
Clay, Loam (Silt), SandExtension Gardener Plant Toolbox
Soil pH
Acid (<6.0), Alkaline (>8.0), Neutral (6.0-8.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, Occasionally WetExtension 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

Two sources report 4 treatments between them. All are shown.

Protocol 1

DerivedN. C. Deno, 1998

Difficulty Moderate Rated by us, not by the source.

Start around March 22, 2027 for a May 3 last frost.

  1. Sow and cover

    Temperature: 70°F 21°C Light: light

No stated waiting before sowing. Then 14 days to germinate.

62% germination in 14 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Veronicastrum p. 66Public domain
Show the original text
Veronicastrum (Scrophulariaceae). V. virginica germ. 70L(62% in 2nd w, 1 st Suppl.). Seeds DS 2 y were dead. *' ..
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Veronicastrum p. 66. 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, 1996

Difficulty Moderate Rated by us, not by the source.

Sow around February 2027 — a date the source gives, not one counted back from a May 3 last frost.

  1. Sow outdoors and leave it

    Sown outdoors in February; up in April.

No stated waiting before sowing. Then 60 days to germinate.

33% germination in 60 days.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Veronicastrum p. 85Public domain
Show the original text
Veronicastrum (Scrophulariaceae). V. virginica germ. 70L(62% in 6-12 d), OT(33% in April from seed placed outdoors in February), 40-70D(4%), and none in 70D or 70 GA-3. It is curious that light and OS are the two effective treatments as this combination is rare.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Veronicastrum p. 85. 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, 1996

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

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

  1. Cold moist stratification

    Duration: 90 daysTemperature: 40°F 4°C

  2. Warm moist stratification

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

about 3 months from start to step 2. Germination happens during step 2; time not stated, 21 days assumed.

4% germination.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Veronicastrum p. 85Public domain
Show the original text
Veronicastrum (Scrophulariaceae). V. virginica germ. 70L(62% in 6-12 d), OT(33% in April from seed placed outdoors in February), 40-70D(4%), and none in 70D or 70 GA-3. It is curious that light and OS are the two effective treatments as this combination is rare.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Veronicastrum p. 85. 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, 1996

  1. Sow and cover

    Temperature: 70°F 21°C Light: dark

No stated waiting before sowing.

0% germination.

Nothing germinated at 70.

Seed Germination Theory and Practice, 1st Supplement — N. C. Deno, 1996 · 1st Supplement, Veronicastrum p. 85Public domain
Show the original text
Veronicastrum (Scrophulariaceae). V. virginica germ. 70L(62% in 6-12 d), OT(33% in April from seed placed outdoors in February), 40-70D(4%), and none in 70D or 70 GA-3. It is curious that light and OS are the two effective treatments as this combination is rare.
Seed Germination Theory and Practice, 1st Supplement, 1st Supplement, Veronicastrum p. 85. Quoted exactly. Every value on this card comes from this record; 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

Add to My Garden

View species page