Question
We laid sod about on month ago.  We thought that we had to wait for the sod to "take" before we mowed it. We mowed our new lawn too short and with an old mower.  Now it looks pretty brown.  About 1/2 brown/1/2 green.  This was two days ago.  It has been raining for the past day and 1/2 and the forecast is overcast for the next two days then rain again for two days after that.  Is there something I can do to help save the grass.
I have just purchased a new reel mower.
Thank you,
Carol  

Answer
Hi Carol,

Mowing new sod or seeded grass too low can cause a "physiologic shock syndrome".  The grass will blanch and brown-out then you may be left with a dead bare-earth area.
This is sometimes called 'scald-scalping'.
Hot weather does not help this situation, and there can be large areas of lawn destroyed.  The grass needs some leaf-surface to make food for the new roots and growing plant tissues, so don't slash-off too much of the grass height early on.


New sod needs lots of watering, so it is good you have been getting some rain.  And it is difficult this time of year to get sod well-rooted with high day temperatures; it may take longer than it would had you started in spring.

Also with new sod, it is a good practice to wait until the sod can pass the 'tug-test' before the first mowing or fertilizing event.  This means the sod is well-rooted (has 'taken' as you say) and cannot be easily pulled up when you try to pull it up.

You did not mention what your grass-type is.
Reel mowers are usually used on hybrid Bermuda sod.  This is a very hardy grass-type and should be able to recover from a slight mower scalping.

While other Bermuda cultivars are kept at around 2.5-3 inches high,....Hybrid Tiff and Tiff-Way sterile-sod Bermudas are meant to be kept very short (sometimes around half an inch high)  with FREQUENT reel-mower service events;...but AFTER the sod is well rooted.

The best you can do is to keep the brown areas well hydrated and try to encourage the remaining sod to get well rooted.  This may take days or several weeks depending upon your top-soil's quality and pre-sodding preparation.

As for what to do...

Wait for it all to pass the 'Tug-Test' ...and ...Do NOT add fertilizers until the sod is well rooted and has been able to stand-up to at least two mowing events,...keep it well watered but not soggy and you should be ok.  

If you are left with totally dead areas, you can take some plugs from the healthy areas to patch things up, or with larger losses, you may be able to get some extra sod squares to make the repairs faster.


Good Luck,
 Jim G.