Jiffy 7 Pellets for Starting Seed 703. Small puck-like wafers of compressed peat encased in a plastic net. When water is applied, the Jiffy 7 expands to form a soft pellet about 4.3 cm (1-3/4″) in diameter and about 5.3 cm (2-1/8″) deep. Seeds or transplants may be directly sown into the pre-formed hole in the centre of pellet. When rooting cuttings, the centre of the swollen Jiffy 7 can be hollowed out to the required depth with a pencil, the cutting can then be inserted. Finish by gently squeezing the dampened peat around the stem of the cutting.