Soil temperature and grass growth

Cool Season Grasses

90F Shoot growth ceases.
77F Root growth ceases.
70F Maximum temperature for root growth of any consequence.

70F Time to plant grasses in late summer.

60-75F Optimum temperature for shoot growth.
50-65F Optimum temperature for root growth.

40F Shoot growth ceases.
33F Root growth ceases.
20F Low temperature kill possible if temperature subsequently drops
rapidly below 20F

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