The best time to plant grass seed in New Hampshire is from late summer to early fall, August through September, when soil temperatures are perfect for promoting a strong root system. This timing ensures your new lawn will thrive.
While it’s also possible to plant grass seed in spring, it’s not ideal. In this article, we’ll explore the best practices for both seasons, helping you achieve a healthy lawn just in time to enjoy the crisp autumn air (or summer barbecues if you decide to plant in spring).
Best time to plant grass seed in New Hampshire
The best time to plant grass seed in New Hampshire is from late summer to early fall, specifically from August through September. However, the exact date will depend on soil temperatures in your specific location.
Here are the ideal planting temperatures for the best grasses suited for New Hampshire:
- Kentucky bluegrass: 59 to 86 F
- Perennial ryegrass: 68 to 86 F
- Tall fescue: 68 to 86 F
- Fine fescue: 59 to 77 F
If you live in cities like Manchester or nearby areas, you can plant as late as the first week of October, but no later than that. However, if you live in cities further north, such as Berlin, which experience colder temperatures earlier, you should have your lawn seeded by the second week of September.
Pro tip: To ensure you’re planting at the right time, check the average soil temperatures in your city at the GreenCast website.
Second best time to plant grass seed in New Hampshire
If you miss the ideal planting window, you can also plant grass seed in spring, from March through May. However, be aware that planting in spring in New Hampshire requires extra care to ensure the newly planted seeds survive through summer.
Here are some tips for successful spring planting:
- Frequent watering: Newly planted grass seeds need consistent moisture, especially during drought periods. Water your lawn more frequently, twice per day, to keep the soil moist but not waterlogged.
- Watch out for weeds: Spring is prime time for weed growth, which can compete with your new grass. Keep an eye out for weeds and manage them promptly.
- Consider pre-emergent herbicides: You can apply pre-emergent herbicides to control weeds like crabgrass, but be sure to check the label for timing instructions. These herbicides can inhibit the growth of grass seeds, so it’s important to follow the application guidelines.
Best time to overseed in New Hampshire
The best time for overseeding your lawn in New Hampshire is the same as for new seeding: late summer to early fall. This period allows the new seeds to germinate and establish well before the freezing temperatures set in.
Overseeding is particularly beneficial if you have thinning areas in your lawn or if you seeded in spring but didn’t achieve the desired results. You can learn how to do it in our guide: 4 Steps to Overseed a Lawn.
Tip: Coupling overseeding with aeration can be helpful. Aeration involves removing small plugs of soil from your lawn, which improves seed-to-soil contact and boosts air and nutrient flow to your new seeds. Check out our guide, How to Aerate Your Lawn, to learn more about it.
FAQ about planting grass seed in New Hampshire
What are New Hampshire’s planting zones?
According to the updated USDA plant hardiness zone map, New Hampshire planting zones span from 3b to 6b. These zones reflect average annual extreme minimum temperatures between -35 F and 0 F, which means that temperatures vary significantly in the state. Most areas in New Hampshire are classified within zones 5a, 5b, and 6a.
How do I plant grass seed in New Hampshire?
Planting new grass seeds involves four basic steps:
- Selecting the best grass seed mix for your area
- Preparing the soil
- Sowing the seed
- Caring for the newly planted seeds
For detailed instructions, check out our guide: How to Plant Grass Seed.
How long does it take new grass seed to grow in New Hampshire?
The time it takes for new grass to grow in New Hampshire depends mainly on the type of grass seed. Perennial ryegrass is known for its quick growth, with germination starting in just 5 days. In contrast, other cool-season grasses, like Kentucky bluegrass, can take up to 30 days to germinate.
Additionally, factors such as soil condition, pH, weather, and maintenance will also influence the growth rate of the new grass seeds.
Call in the pros
Now that you know when to plant grass seeds, it’s time to get your hands dirty and start planting. However, if you’d rather “live free” and enjoy the beautiful fall foliage in New Hampshire, consider calling a lawn care professional near you. Let the experts handle the work while you soak in the stunning scenery.
Main Image Credit: Doug Kerr | Flickr | CC BY-SA 2.0
