Growth cabinet studies were conducted on the effect of temperature, pH and light exposure on seed germination of Brazil pusley, common ragweed, Florida beggarweed, hairy beggarticks, ivyleaf morningglory, Johnson grass, prickly sida, redroot pigweed, sicklepod, strangler vine, tall morningglory and yellow nutsedge. When averaged over all species and temperatures, highest weed seed germination was recorded in the temperature regime of 25 to 35OC, maximum being at 30OC. Lower temperature of 15OC inhibited germination of Johnson grass, Brazil pusley, Florida beggarweed, redroot pigweed, prickly sida and yellow nutsedge. Germination of common ragweed and ivyleaf morningglory was highest at 20OC, and significantly decreased above 35OC. Higher temperatures (30 to 40OC) were less inhibitory to germination of redroot pigweed, Johnson grass, Florida beggarweed, prickly sida and yellow nutsedge compared to other weed species. Tall morningglory and hairy beggarticks had high germination rates from 15 to 35OC. Germination of prickly sida and Florida beggarweed was highest between 25 to 40OC and sicklepod from 20 to 40OC. Strangler vine germination was highest at 30OC and decreased significantly with any increase or decrease in temperature. No weed seed germinated at pH 3, except yellow nutsedge. A pH range of 5 to 11 had no adverse effect on germination, when data were averaged over species. Germination of prickly sida was highest at pH 9 and any increase or decrease in pH resulted in reduced germination. Yellow nutsedge seed germinated 14% at pH 3 compared to 47% at pH 7. Germination was not inhibited for any test species in dark, except Brazil pusley. After 168 h, germination of Brazil pusley ranged from 2 to 10% with light exposure of 0 and 16 h, respectively, before placing them in dark. Under alternate light and darkness cycle of 12 h, germination of Brazil pusley increased to 59%. Other than Brazil pusley no other species exhibited the photoblastic effect.