The best time to plant grass seed in Montana is in the fall, between mid-August and mid-September, or in the spring, in late April and May. If you’re planting cool-season grass, the temperature should be at least 55 degrees, or 65 degrees if you’re planting warm-season grass.
We recommend planting in the fall because seeds have time to establish before Montana’s hot, stressful summer weather.
In this article, we’ll talk about the ideal planting times for cool-season versus warm-season grasses and how Montana’s different climates affect your choice of grass seed.
Best Months to Plant Grass Seed in Montana
The best time to plant grass seed in Montana is between the middle of August and the middle of September. The heat of the hot Montana summers can cause stress on plants, so planting during this time allows the grass to establish itself in an environment more conducive to healthy plant growth. Also, annual weeds don’t have time to produce seeds during this time of year, so weeds are less likely to be a problem.
Spring vs Fall Planting
You can also plant grass seeds in late April and May, but the seeds will have to deal with the summer heat before they are established. So while you can plant grass in the spring, it is best to seed in the fall, around Labor Day. This allows the grass time to establish healthy roots before the summer stress.
When to Plant Cool-Season vs Warm-Season Grasses
Both cool-season and warm-season grasses perform well in Montana. However, some varieties grow better in certain regions.
Cool-Season Grasses: Whether you are planting cool-season grasses in the fall or spring, these grasses are best planted when the soil temperature is 55 degrees Fahrenheit.
Warm-Season Grasses: Warm-season grasses should be planted between the end of spring and summer when the beneath-the-surface soil temperature is approximately 65 degrees Fahrenheit. These turf varieties go dormant and turn brown in the Montana winters. They regain their green color when it warms up, and warm-season grasses are more heat and drought-tolerant than cool-season grasses.
The Best Grass Types to Plant in Montana
Planting a mix of grass species is best for most of Montana. Kentucky bluegrass, Chewings fescue or creeping red, and perennial ryegrass are an optimal mixture for lawns with moderate irrigation, sunlight exposure, and fertility levels. According to Montana State University Extension, shady lawns benefit from the same mixture but with a higher quantity of fescue.
Grass varieties that work best in the semi-dry eastern Montana region perform optimally when planted alone. Sheep fescue, hard fescue, or the latest turf-type fescue varieties work well in this area.
Warm-season varieties like blue grama and buffalograss grow well in the driest areas of the state and lawns with no irrigation. Streambank wheatgrass, crested wheatgrass, or smooth bromegrass also grow well and can be mixed.
LawnStarter’s “Best Grass Seed for Montana” guide offers a more comprehensive look at the grass seeds that work best in each area of the state.
When to Plant Pasture Grass
The best time to plant pasture grass is the same as planting lawn grass in Montana in general, with some specific guidelines regarding temperature requirements. Seed pasture grass in the spring or fall.
Spring vs Fall Planting
Spring: Cold or freezing temperatures may hasten germination or growth. The goal is to plant as early as possible or when temperatures remain consistently between 45 and 75 degrees Fahrenheit.
Fall: Plant seeds 6 to 8 weeks before Montana’s typical first frost, which is between August and September, so seeds are sufficiently established before winter. Alternatively, you can plant when temperatures are consistently lower than 60 degrees Fahrenheit. This is usually between late October and early November. Seeding during this time allows for seed dormancy so germination is prevented until it warms up again in the spring.
FAQs About When to Plant Grass Seed in Montana
When is it best to restart a lawn?
If your lawn looks so bad you feel like you need to re-establish it, go ahead and do so. Destroy your current grass using synthetic chemicals or organic methods (see “4 Ways to Remove Lawn Grass”), till the lawn, remove any dead grass, fertilize the soil, and spread the new seeds.
However, if your lawn has a few dead patches or is thin, you may want to get rid of the dead grass, fertilize the empty patches, and lay down new seeds (overseed) in the area.
When is the best time to fertilize grass in Montana?
The best time to fertilize depends on where you live in the state. However, the typical ideal times to feed your grass are around the end of May, the beginning of September, and mid-October about four weeks before the ground freezes.
Most Montana home lawns need 2 to 4 pounds of nitrogen per 1000 square feet of lawn annually. The goal is to give the grass no more than 1.5 pounds of nitrogen per 1000 square feet at any given time, so apply fertilizer two to three different times.
When is the best time to water grass in Montana?
The best time to water grass is early in the morning. In general, water the lawn infrequently and deeply.
Your soil type determines how to water your grass. For example, clay soils need to be watered slowly, because the soil holds onto water. Sandy soils need irrigation more frequently, as this soil type absorbs water, drains, and dries out quickly. Read our guide: “How Often to Water Grass Seed.”
When to Call a LawnStarter Pro
You want your lawn to look as picturesque as the rest of Montana. While you can chance it and do it yourself, LawnStarter has pros that can test your soil, amend it if necessary, and plant grass seeds best suited for your area and yard’s climatic conditions.
Our guide on lawn mowing tips can give you some great pointers. But when you’re ready to turn the work over to the pros so you can do something else with your time, LawnStarter experts are ready to mow, trim, edge, and overseed to give you an impressive and thriving lawn.
Main Image Credit: Lawn in front of Arnold Graf House in Billings, Montana / Drmccreedy / Wikimedia Commons / CC BY-SA 4.0
