Four O'Clock Seeds (Pink) Four O'Clocks, so named because they typically bloom late in the afternoon, are among the most colorful, fragrant, and robust of all flowers that can be grown from seed. They're very versatile too, as the seeds of the Four O'Clock can be sown directly into the soil or into pots or other containers such as barrels. Plant Four O'Clock seeds in the spring for late summer/early autumn bloom.