Watering until germination (3–4 weeks)

Why constant moisture matters

A grass seed that has started to germinate and then dries out dies. It cannot pause and restart. That is why newly sown lawns fail far more often from watering than from bad seed. The aim for the first three to four weeks is a surface that never dries out, without being soaked.

How much and how often

• Give about 3–4 mm (⅛ in) of water every morning, enough to keep the top centimeter dark.
• On hot, windy or sandy sites, add a second light watering in the early afternoon.
• Use a fine spray or sprinkler. A strong jet washes seed into puddles and leaves bare patches.
• Stop if water starts to puddle; it should soak in, not pool.

If you are not there every day

Seed will not survive a weekend-only schedule in dry weather. Set up a sprinkler on a timer before you sow, or lay sod instead, which tolerates gaps far better.

When to change

Once the seedlings are up and have had their first mow, water less often but more deeply, so the roots grow down instead of staying at the surface.