Planning the year
See Chicago scheduleFertilizer
Summer iron (foliar) application
A foliar iron spray darkens the lawn's color without forcing the leaf growth a nitrogen feeding would, which is exactly what summer-stressed turf needs. Iron is taken up directly through the leaves, so results show in days rather than weeks. Shallow soil temperatures are in the action band at 72°F at 2 inches at the Shabbona 5 NNE sensor, 62 miles from your location.
Source: Shabbona 5 NNE station
