Usually planted in the early fall, cool-season grass seeds prefer daytime temperatures ranging from 60 to 75 F. With this temperature range, the soil itself is usually between 50 and 65 F  the right environment for germination.
Your grass type must be either a cool season grass or a warm season grass. The time of planting will be determined by the type of grass -- click on the link below to find out the best time to plant your grass! 1  Cool Season Grasses (Tall Fescue, Ryegrass, Bluegrass, Fine Fescue, Bentgrasses, etc.). 2  Warm Season Grasses (Bahiagrass, Bermuda, Centipede, Zoysia, Carpetgrass, Buffalograss, etc.). Cool season grass germinates best when the soil temperatures are between 50 and 65 degrees F. These temperatures usually occur when the daytime air temperatures are between 60 and 75 degrees. High temperatures of summer can cause these plants to go dormant and thus planting during summer is asking for problems. Usually planted in the early fall, cool-season grass seeds prefer daytime temperatures ranging from 60 to 75 F. With this temperature range, the soil itself is usually between 50 and 65 F -- the right environment for germination. Warm-season grasses, like St. Augustine (Stenotaphrum secundatum), which grows in U.S. Department of Agriculture plant hardiness zones 8 through 10, rely on daytime temperatures hovering around 80 degrees Fahrenheit for successful germination. But air temperature may not be the best indicator of soil temperature. Because of this, you may have to plant both warm and cool weather grasses. If you opt for this consider planting cool weather grass seed in the early fall and then in the early spring overseed your lawn with warm weather grasses. However, there are some general guidelines to follow: 1  Seed cool weather grass seeds in late summer to early fall. 2  Seed warm weather grass seeds in early spring and into the summer. 3  Plant in regards to the grass seed and not the area you live in. This is determined by the season of the grass type's active growth period. This critical information applies to lawn, sports turf and pasture grass. It does you no good to buy and plant a warm season grass only to find that the hard freeze that is normal for your winter will kill out the grass. Same goes for cool season grasses when the summer temperatures of the South shrivel your grass to nothing.  This critical information applies to lawn, turf and pasture uses for grass types. It does you no good to buy and plant a warm season grass only to find that the hard freeze that is normal for your winter will kill the grass. Same goes for cool season grasses when the summer temps shrivel your grass to nothing. Finding the right grass seed or grass seed mixture is an important step in planting and obtaining a great lawn. GO TO STEP 1- Determine if you need warm season, cool season or a grass seed mixture.  Grass seed not in good contact with the soil cannot warm up correctly for successful germination. Seeds rely on warmth and soil moisture to swell and sprout. If your seeds remain at their ideal temperature range and are planted no more than 1/4 inch deep, you should see germination after three weeks. Warm-season grasses, like St. Augustine (Stenotaphrum secundatum), which grows in U.S. Department of Agriculture plant hardiness zones 8 through 10, rely on daytime temperatures hovering around 80 degrees Fahrenheit for successful germination. But air temperature may not be the best indicator of soil temperature. 1 Avoid the hottest season or occasional heat-spells when planting. 2  Watering new grass seed is enough of a challenge without taking on the heat as an enemy. 3  If you have no choice, be vigilant and accept the need to apply water more frequently as it dries out more quickly.  Fall Planting Risks For Warm Season Grass: In the fall you should not plant a warm season grass later than 60 days before first frost (in southern areas) and 90 days before first frost in more Northern cooler locations. Cool season grasses grow best when the soil temperatures are between 50 and 65 degrees F. These temperatures usually occur when the daytime air temperatures are between 60 and 75 degrees. High temperatures of summer can cause these plants to go dormant and thus planting during summer is asking for problems. Even with careful soil preparation and seed spreading, creating a lawn from scratch may backfire if you choose the wrong time of year to sow seeds. Like many plants, grass seeds need warm soil to germinate -- cold weather often stunts growth, leaving you with a barren landscape. Warm-season grasses, like St. Augustine (Stenotaphrum secundatum), which grows in U.S. Department of Agriculture plant hardiness zones 8 through 10, rely on daytime temperatures hovering around 80 degrees Fahrenheit for successful germination. But air temperature may not be the best indicator of soil temperature.
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how warm does it need to be to plant grass seed