To alleviate high-temperature-induced reductions in seed germination, emergence, and seedling uniformity in celery (Apium graveolens L.), seeds were primed via solid matrix priming (SMP); 0.5 g celery seeds was incubated at 15C with 10 g calcined clay and 2 ml water. After 2 days, 1, 2, 3, or 4 ml water or 1% NaOCl solution was added and seeds were kept for 2, 4, 6, 8, 10, 12, and 14 additional days. The germination percentage and coefficient of germination velocity (COV) were calculated for each treatment at 15 and 30C. The seeds primed with NaOCl gained significantly less moisture after 8 days of priming than those treated with water, regardless of the volume added. Germination of nonprimed seeds was 83% and 2% at 15 and 30C, respectively. Final germination at 30C increased to >80% when seeds were primed with 3 or 4 ml NaOCl solution or 3 ml water for >10 days. SMP treatment significantly reduced the negative effect of high temperature on celery seed germination.