It never stops in my opinion but spring and fall are the primary growth periods that we know. It slows during summer but it IS going on. P and K will aid the slow growth in repairing damaged tissue year round. I see it all the time in my area. I've had customers drop roots 4" to 5" more June thru August accomplished simply by raising the mowing height 2" and two apps per month of K at 1#/1000. Especially under heavy rain conditions. I saw it. I also imagine summer weeds, grassey and broadleaf developed roots over summer. Why would turf grass roots differ? Humates baby humates.
Last edited by turfmd101; 07-14-2013 at 08:35 PM.