Paul I used this mix only 4 times. 1. to moisten my seed starting mix. 2. to moisten my potting mix 3. applied 1 time about 4 weeks after potting. 4. Moistened potting soil with it when I transfered plants to 1 or 3 gal pots. A 42 oz concentrate makes 252 gal. I think for your # of plants that is more than enough. L.B. L.B. I had over 300 seedlings to plant this spring & lost 4 flats with 72 seeds in each one due to a power outage. I probably need the 42oz. container & then some. Do you only use the "tea" to water seedlings? Paul