Hi All,

I would like to overseed existing turf with perennial rye. In all my reading there seems to be debate on how short to cut your grass if you are attempting to overseed, especially with a quicker germinating species like annual or perennial rye as opposed to slow germinating kbg for example. The majority seems to lean towards scalping the lawn. I do not want to scalp my lawn and I would prefer to not take it so low that all the grass will go dormant and brown as a result of shock. This is a step above overseeding maintenance and a step below a renovation.

My question is, assuming irrigation is available for proper watering on a daily basis (multiple if necessary), and considering that at the root zone/soil surface the seed should continue to remain moist based on the shelter of the surrounding established turf, as the current grass tends to be slightly damp at the soil, is 2" short enough to allow rye the necessary sun, while providing the moisture it needs to germinate, assuming the established turf can remain cut low enough (3"?) to keep sunlight available to the seedlings?

I am aware that fall and spring are best time to overseed based on day/night temperatures, but if I wanted to overseed a quicker germinating grass like rye, could I do it now knowing the success rate would be lower, and then again end of august as part of my planned fall overseed? I have a many bare and thin spots I would at least like to begin establishing prior to end of August if it will take. I am okay with spending a 100 or so on seed that may end up being a throw-away.

Thoughts and opinions?