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Citrullus lanatus

Afghan-melon · Water Melon · Bastard-melon · Watermelon

Family CucurbitaceaeGenus Citrullus

A striped green watermelon lying on the ground among lobed leaves and trailing stems
FruitKumonCC BY 2.0

About the plant

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

The plant

Habit
Annual, Vegetable, Vine, Warm Season VegetableExtension Gardener Plant Toolbox
Habit
annualPlants of the World Online
Height
4-8 in10-20 cmExtension Gardener Plant Toolbox
Spread
5-10 ft1.5-3 mExtension Gardener Plant Toolbox
Flower
Gold/YellowExtension Gardener Plant Toolbox
Blooms
Spring, SummerExtension Gardener Plant Toolbox
Native range
Egypt, Ethiopia, LibyaGBIF Backbone Taxonomy

Growing conditions

Sun
Full sunExtension Gardener Plant Toolbox
Soil
Loam (Silt)Extension Gardener Plant Toolbox
Soil pH
Neutral (6.0-8.0)Extension Gardener Plant Toolbox
Moisture
Good Drainage, MoistExtension 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; GBIF Backbone Taxonomy — Global Biodiversity Information Facility.

Worth knowing

  • Early watermelons were bitter, with yellowish-white flesh, grown for their water to store through dry seasons. The sweet kind was bred later. It was first domesticated in Sudan. Wikipedia: Watermelon

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

Protocol 1

DerivedN. C. Deno, 1998

Difficulty Low Rated by us, not by the source.

Start around March 30, 2027 for a May 3 last frost. Too late for spring 2027 — that needed starting on March 29, 2024.

  1. Dry storage

    Duration: 1095 daysTemperature: 70°F 21°C

  2. Sow and cover

    Temperature: 70°F 21°C

about 3 years from start to sowing. Then 7 days to germinate.

90% germination in 3–7 days.

Seed Germination Theory and Practice, 2nd Supplement — N. C. Deno, 1998 · 2nd Supplement, Citrullus p. 24Public domain
Show the original text
Citrullus (Cucurbitaceae). C. vulgaris seeds DS 3 y germ. 70(90% in 3-7 d) which is virtuaiiy the same as the 100% germination of seeds DS 6 m (recail that fresh seeds germ. only in light, First Suppl.).
Seed Germination Theory and Practice, 2nd Supplement, 2nd Supplement, Citrullus p. 24. 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 Low Rated by us, not by the source.

Start around March 13, 2027 for a May 3 last frost.

  1. Clean the flesh off the seed

  2. Leach in running water

    Duration: 7 days

    Washed and cleaned daily for 7 days.

  3. Sow and cover

    Temperature: 70°F 21°C Light: light

7 days from start to sowing. Then 16 days to germinate.

90% germination in 5–16 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Citrullus p. 118Public domain
Show the original text
Citrullus (Cucurbitaceae). C. vulgaris is the watermelon. Fresh seeds require light or GA-3, but these requirements disappear on DS. Two strains of commercial seed were obtained in April and had been DS for about 6 m. These germ. 70-90% in either 70L or 70D. In contrast, fresh seeds WC for 10 minutes germ. 70L(90% in 5-16 d), 70D GA-3(50% in 5-22 d), and 70D(none). Part of the sample in 70D was shifted to 70L after 2w whereupon 90% germ. in the 3rd d confirming the effect of light. Fresh seeds WC for 7 d gave about half as much germination. The efficacy of just 10 minutes WC suggests that there are no inhibitors in the fruit. DS for 2 m at 70 does not affect the 100% germ. in 70L, but the germ. in 70D increases to 13% in 2nd w confirming the disappearance of the light requirement on DS.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Citrullus p. 118. 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 Moderate Rated by us, not by the source.

Start around March 7, 2027 for a May 3 last frost.

  1. Clean the flesh off the seed

  2. Leach in running water

    Duration: 7 days

    Washed and cleaned daily for 7 days.

  3. Gibberellic acid soak

  4. Sow and cover

    Temperature: 70°F 21°C Light: dark

7 days from start to sowing. Then 22 days to germinate.

50% germination in 5–22 days.

Seed Germination Theory and Practice, 2nd ed. — N. C. Deno, 1993 · Ch. 20, Citrullus p. 118Public domain
Show the original text
Citrullus (Cucurbitaceae). C. vulgaris is the watermelon. Fresh seeds require light or GA-3, but these requirements disappear on DS. Two strains of commercial seed were obtained in April and had been DS for about 6 m. These germ. 70-90% in either 70L or 70D. In contrast, fresh seeds WC for 10 minutes germ. 70L(90% in 5-16 d), 70D GA-3(50% in 5-22 d), and 70D(none). Part of the sample in 70D was shifted to 70L after 2w whereupon 90% germ. in the 3rd d confirming the effect of light. Fresh seeds WC for 7 d gave about half as much germination. The efficacy of just 10 minutes WC suggests that there are no inhibitors in the fruit. DS for 2 m at 70 does not affect the 100% germ. in 70L, but the germ. in 70D increases to 13% in 2nd w confirming the disappearance of the light requirement on DS.
Seed Germination Theory and Practice, 2nd ed., Ch. 20, Citrullus p. 118. 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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