GRASS SEED NEEDS TO BE WARM AND MOIST TO GERMINATE
Water is the most important part of seed germination that the homeowner can control. Watering should be done every day, early in the morning, and if at all possible, early in the afternoon to keep the seeds damp. The more faithful, the better the outcome will be.
Keep grounds damp, or if covered with straw, the straw damp. This is done best with a hand nozzle or a wand (oscillating) type sprinkler. A lot of water is not necessary and caution should be taken of not making puddles.
When seeds have sprouted up, watering needs to continue. This is the most important time to water. The easiest way to measure your watering practices is by using coffee cans. Set up a couple of cans in an area where the sprinkler will be operating. Water until approximately 1/4 inch of water is in the can. Now move can and sprinkler to another area and repeat making sure to empty can on each move.
When grass reaches approximately 4″ to 5″ tall it should be cut with sharp blades. Use caution when turning mower around so you don’t tear up the grass. You should increase your watering to approximately 1″ to 2″ of water per week.
When grass has been cut at least four times, it can be fertilized with a quality fertilizer and should now be strong enough to subject to weed killers. (When in doubt, wait a few more cuttings).
Please note in the event of no rain or no watering, your grass will be the first to die. The older established grass will become dormant and normally recover.