“Certain epiphytic orchids of the tropical rain forest produce the world’s smallest seeds, up to 35 million per ounce.”

Botanical Record Breakers

I don’t actually know, but from the seeds I’ve seen I want to say it’s a banana seed. They’re so tiny!

I’ve always liked the mustard seed . It starts as a diminutive thing, but ends up as a giant shade bringing tree.

What about poppy seeds?

While the seed @marinelife linked to is small (85 microns), spermatozoa can average a size of about 40 microns. After all, the word sperm/sperma comes from the greek word, ‘seed’.

@gasman The poppy seed is about 1mm. (1,000 microns)

@rpm_pseud0name 40 microns includes the tail! The head of a human sperm is only 5 micrometers in length. But sperm (and pollen, the plant analog of sperm) are haploid and only need to deliver a small payload of DNA to fertilize the ovum / ovule / seed. So it shouldn’t count.

I agree with bubba3778, I consider mustard seed as the smallest because from it comes a very big tree. Although poppy seeds are smaller.

Sperm? Millions upon millions in just one ahem squirt ;)