D.J. Cantliffe
The emergence of direct seeded vegetables either in the field or in a transplant production system can be reduced by numerous environmental and physical stresses which commonly occur at the time of sowing. In the field, temperature extremes, heavy rainfall, drought, and soil compaction can greatly alter total plant stands and seedling uniformity. Conditions of extremes in temperature and moisture can limit stand uniformity in the greenhouse. A number of seed treatments, especially priming, have been shown to improve germination and emergence of cabbage, carrot, celery, lettuce, pepper, and tomato. An additional improvement in stand uniformity for a number of vegetable species has been obtained when seeds are sown with soil amendments. Use of plug mix (peat:vermiculite), gel mix (peat:vermiculite:gel combination), and/or calcined clay amendments (GrowSorb) greatly improve emergence and plant uniformity in pepper, tomato, cabbage, and lettuce sown under temperature and water stress.
Cantliffe, D.J. (1989). STAND ESTABLISHMENT. Acta Hortic. 247, 175-179
DOI: 10.17660/ActaHortic.1989.247.31

Acta Horticulturae