There should be plenty of nutes to last atleast 1 month for sure with seedlings after you transplant em just water them, I go by the weight of the container.Get in the habit of knowing the feel when you have watered good then wait till it feels light works for me.Are the ole 2 digit rule stick finger in soil if its dry to the second knuckle on index finger water.The soil im using now is out of Canada its called Sunshine Professional makeup of 0.1 0.1 0.1 But has alot of micro nutes as i like to add my own Nitrogen staying away from urea will help the taste dramatically,GL JC.BEECHY.Not being rude but use the old formula KISS,keep it simple,stupid as i was told about 10 yrs ago..