🍉 Where do seedless watermelons come from?

A watermelon is part of the gourd family — the same plant family as pumpkins, cucumbers and cantaloupes. They all sprawl along vines, and they all carry separate male and female flowers, so pollen has to be carried from one flower to another. Insects, mostly bees, do the carrying.

Basis: Botany: watermelon, pumpkin, cucumber and melon all belong to the gourd family (Cucurbitaceae), and these crops have separate male and female flowers that are insect-pollinated.

A seedless watermelon plant is a hybrid. Breeders cross a normal watermelon with one whose chromosome sets have been doubled. The plants that come out have three sets of chromosomes instead of two — and three sets cannot be split evenly in half, so proper seeds never finish forming.

Basis: Plant breeding: seedless watermelons are triploid hybrids, made by crossing a chromosome-doubled (tetraploid) parent with a normal (diploid) one; the odd number of chromosome sets prevents normal seed development.

That also means a seedless plant cannot supply its own good pollen. So growers plant ordinary seeded watermelons in the same field as pollinizers, and bees carry that pollen over to the seedless flowers. No pollen delivery, no melon.

Basis: Standard commercial watermelon growing: triploid (seedless) plantings need a diploid pollinizer variety in the field, and bees move the pollen between them.

The pale, soft white specks you still find in a seedless slice are empty seed coats — seeds that started and then stopped. That is why they are chewable instead of hard and black.

Basis: Horticulture: the white “seeds” in a seedless watermelon are undeveloped seed coats.