Did you know that every blade of grass growing in your yard was once a tiny grass seed? Grass seeds come in many different varieties that thrive in different conditions, but all types of grass follow the same essential growth and harvesting process.
Read on to learn everything you need to know about grass seed.
The mighty life of a tiny grass seed
Fortunately for us, grass seed is dormant until specific conditions are met. This protection measure keeps seeds from germinating until the seed has adequate moisture, oxygen, and the correct temperature.
When these growing conditions are present, it likely indicates a favorable growing environment, and the grass has a better chance of growing and passing on its genetic information to future generations.
This is fortunate because it means grass seeds can sit dormant in a package on a store shelf for two to three years if they’re not exposed to adequate moisture. It also means you can store excess seed in your garage or basement after planting, in case you need to overseed thin or bare spots.
Once the required conditions are met (e.g., planting where the seed is exposed to plenty of moisture, oxygen, and the right temperature), a seed will immediately start absorbing water in a process called imbibition. The seed dramatically increases in size, the hard seed coat starts softening, and it starts to wake up from its dormant state.
As the seed swells with water, the moisture triggers respiration and metabolism of the storage reserves in the endosperm, activating enzymes needed for growth processes. Cellular division starts inside the seed to form the primary root, the radicle. The seed coat ruptures, and the radicle pushes out to take hold in the soil.
Soon after emergence, the radicle begins absorbing nutrients and moisture to drive cellular division that forms an initial shoot. The shoot pushes out of the seed and naturally grows upward, working its way toward the sunlight. Within a few days of the start of germination, the blade peeks through the soil surface.
Once that grass blade has access to sunlight, it begins photosynthesis, and growth takes off exponentially. Rapid cellular growth creates a bunch of small roots, and the grass grows taller.
Fully-grown grass features a crown just above the soil, a tube-like sheath, and one or more blades growing out of that sheath. Different grass varieties will have their own appearances, but the growth process is similar for all types of grass seeds.
As grass seed continues to mature, its goal is to start a new generation before it dies so it can pass along its genetic information. When the conditions are correct or if the grass is under significant environmental or abiotic stress, processes within the blade change to promote flowering so the grass can produce a seed head.
How grass seeds are harvested
You mow your lawn to keep it looking sharp, well-manicured, and walkable. If you didn’t mow your lawn, those blades of grass would keep growing to their full height and develop small flowers on the tops of the blades, known as florets.
Like any other plant, these grass flowers require pollination to form seeds.
Wind and bugs carry pollen from male florets to female pistils. The pollen gets caught by a sticky part of the pistil known as the stamen; the pistil then closes around the pollen and starts to form a seed.
About 20 to 30 days after pollination, the seeds reach full maturity, and the plant naturally tries to release the seeds so they will hit the ground and germinate. It’s at this stage that seeds are commercially harvested.
Grass farmers will let their grass fields go unmown at the end of the primary growing season. Large clumps of seeds develop off of each tall blade. The farmers wait until the seeds mature and then cut the entire grass field.
Conventional grain combines are often used with a few adjustments to handle turfgrass seeds.
As the combine cuts the grass, large rotating headers on the front feed the grass into the machine, where the seed is thrashed from the blade. The seeds are collected in a hopper, and the blades are discarded out the back of the combine onto the field.
If you want to, you can harvest your own grass seeds. You would need to trim the seed heads, sift the cuttings to remove unwanted bits of grass, and store the seeds until the following season. This process takes a lot of effort and can be unreliable, so most lawn care professionals leave the harvesting to the grass farmers.
Factors that define types of grass seeds
When buying new grass seed for your lawn, look at the back of the package for the variety’s characteristics. You will find a list of features like preferred weather conditions, mowing height, and soil requirements. This information will help you select a grass seed or blend that works perfectly for your lawn.
- Texture defines the width of each grass blade and ranges from coarse to fine.
- Mowing height dictates the length to which the grass should be cut for optimal health.
- Germination speed indicates how many days it will take for the first leaves to sprout.
- Germination percentage is the expected number of seeds that will grow from that package of grass. The federal government requires all grass seed manufacturers to run tests and accurately print this information.
- Wear resistance and recovery time decide how “tough” a grass variety is to foot traffic and use. Some species recover quickly, while others are rather delicate.
- Heat and cold tolerance determine how well the grass will handle specific weather conditions.
- Shade tolerance determines how much light the grass needs to grow.
- Salinity, nitrogen, and pH requirements determine how well the grass seed will react to certain soil types.
- Establishment rate indicates how quickly the grass will overtake a new environment.
There are thousands of different grass seed varieties available across the world. Choose one that can handle your local weather conditions, will thrive in your soil, withstand your yard’s activity, and has the texture you want for your lawn.
Hot and cold: the primary types of grass seed
Turfgrass seeds are divided into warm-season grasses and cool-season grasses based on how and where they grow.
Warm-season grasses thrive in hot weather conditions, so they are usually grown in the southern part of the country. These grasses show substantial growth in the spring and summer and turn brown when cold weather arrives. As they are adapted to warmer climates, they tend to need less water than their cool-season counterparts and are more heat and drought-tolerant.
Cool-season grasses show the most growth in the spring and fall when temperatures are moderate; they go dormant through the winter, and growth slows considerably during the summer heat. These grasses are preferred for lawns in the northern part of the country, where the weather conditions are more irregular, and shade is more common. Cool-season grasses are adapted to survive through harsh winter conditions.
In southern climates, some lawn care professionals and homeowners overseed their warm-season lawns with cool-season grass to maintain a green appearance all year. This technique uses a combination of warm and cool-season grasses chosen for their compatibility.
Popular grass seed varieties
There are thousands of different grass seeds and varieties. Here are the most popular types of grass seeds used for US lawns.
Warm-season turfgrasses
St. Augustine grass (Stenotaphrum secundatum)
St. Augustine grass is one of the South’s most commonly grown warm-season grasses. The dense, blue-green turf has broad blades and is highly adapted to warm, humid regions. It grows slowly and requires plenty of water for good growth.
Unlike most warm-season turfgrasses, some St. Augustine grass cultivars are shade tolerant, making them useful in all types of yards regardless of sun exposure.
Note: For more information on St. Augustine grass, check out Lawn Love’s guide.
Buffalograss (Bouteloua dactyloides)
Native to the North American plains, buffalograss is hardy and easy to maintain. Homeowners across the South adore this heat-resistant, drought-tolerant, fine-textured, warm-season perennial grass. It grows low to the ground and spreads quickly to form a dense, soft carpet of curling leaves, inviting you to stroll barefoot through it.
Buffalograss thrives with little supplemental irrigation and needs infrequent mowing. It has good disease tolerance and pest resistance.
Note: For more information on buffalograss, check out Lawn Love’s guide.
Bermudagrass (Cynodon dactylon)
Bermudagrass is valued for its exceptional drought and heat tolerance and ability to withstand and recuperate quickly from heavy use. Many southern US homeowners rely on this medium-coarse textured grass because of its resilience. It also can be mowed exceptionally low, making it popular on golf courses.
Note: For more information on Bermudagrass, check out Lawn Love’s guide.
Centipedegrass (Eremochloa ophiuroides)
Centipedegrass is a favorite with homeowners who want a minimal upkeep yard. It’s common across the South and grows best in sandy, acidic soils. With low maintenance needs regarding fertilization and mowing, it’s often called the “lazy man’s grass.”
Unlike other warm-season turfs, centipedegrass doesn’t go dormant and brown in the winter. However, this means it doesn’t tolerate cold as well. Extended temperatures below 5°F can cause severe damage or kill centipede.
Note: For more information on centipedegrass, check out Lawn Love’s guide.
Zoysiagrass (Zoysia spp.)
Zoysiagrass is one of the most cold-tolerant commonly grown warm-season grasses and has good shade, salt, and foot-traffic tolerance. The coarse-textured, light green blades grow vigorously during the summer heat to produce a dense, attractive lawn. Of the 11 or so Zoysia species available, Zoysia japonica is one of two species widely grown in the southern United States.
However, Zoysiagrass is slow to grow and establish, so starting a lawn from seed is an intensive, hands-on process.
Note: For more information on Zoysiagrass, check out Lawn Love’s guide.
Cool-season turfgrasses
Kentucky bluegrass (Poa pratensis)
Kentucky bluegrass (KBG) is a cool-season grass common across the entire northern hemisphere and revered as a premier turf type across much of the United States. This grass is dark green, has a medium texture, and grows quite densely to create a beautiful, thick carpet of lawn. It recovers quickly from foot traffic, and damaged or bare spots fill in quickly.
Note: For more information on Kentucky bluegrass, check out Lawn Love’s guide.
Ryegrass (Lolium spp.)
Ryegrass is available in annual and perennial varieties.
Since annual ryegrass (Lolium multiflorum) dies out after a single season, it is often used as a temporary lawn to stabilize new plantings or add winter color to dormant warm-season lawns in the South. It germinates quickly and will help hold the soil in place, while other, slower-to-germinate seeds take time to establish.
Perennial ryegrass (Lolium perenne) is typically grown as a permanent grass. It does best in colder weather conditions and creates a fine-textured lawn. While perennial ryegrass can be grown by itself, many people mix it with other grass species for improved characteristics. Perennial ryegrass is grown with Kentucky bluegrass for better cold tolerance and fine fescue for better shade tolerance.
Note: For more information on perennial ryegrass, check out Lawn Love’s guide.
Fine fescues (Festuca spp.)
Fine fescues are a group of five closely related, similar-looking grasses with low maintenance needs and fantastic shade tolerance. These easy-to-care-for turfgrasses all have fine textures and are commonly used in cool-season grass seed mixes with Kentucky bluegrass to create a blend that thrives in a mix of sun and shade. The KBG thrives in bright, sunny lawn areas; the fine fescue establishes and grows well in shady spots.
Most fine fescue varieties prefer cool, humid, temperate climates, so they thrive in northern climates, especially New England and the Pacific Northwest. Some have improved heat tolerance through breeding, so they can grow in the northernmost areas of the transition zone.
Note: For more information on fine fescue, check out Lawn Love’s guide.
Tall fescue (Festuca arundinacea)
Tall fescue grass is a medium to dark green bunchgrass that forms upright clumps and propagates by sending out vertical shoots known as tillers. It grows best in full sun but tolerates partial shade, especially if it gets a break from the hot sun during the afternoon’s heat.
The grass sends roots 2 to 3 feet into the ground, giving it excellent drought tolerance. Most times, it doesn’t need any supplemental irrigation. If you’re looking for low-maintenance, cool-season grass, tall fescue should be high on your list of options.
Note: For more information on tall fescue, check out Lawn Love’s guide.
Growing a monostand versus a mixed seed blend
When buying seed for your lawn, you can grow a monoculture (i.e., one straight type of grass) or buy a mixed seed blend.
Growing a monostand has its advantages. The main one is a beautiful, uniform turf — all the blades are the same color and thickness. When you grow one type of grass, the growth rate is even across the whole lawn, so it looks freshly mowed for longer.
However, many homeowners nationwide grow lawns containing different turf types. A grass seed blend combines multiple grass types with compatible growth seasons and soil requirements. The blend may contain different cultivars of a single species or different species.
Blends are popular for lawn grass because they improve disease, insect, and drought resistance. The genetic diversity of different grass types is helpful if your yard is a mix of sun and shade because you’ll benefit from the different species.
That said, mixed grass seed blends are much more common where cool-season grasses are grown. Mixes are also great for transitional zones that don’t fall easily into cold or warm-season categories. It’s commonplace to find a blend of two or more KBG varieties or a mix of KBG and perennial ryegrass as a sun and shade mix.
The problem is that you are severely limited when buying warm-season grass blends. Since there’s such a marked difference in the traits — color, shade tolerance, watering needs — of the different warm-season grasses, they typically aren’t blended. It’s not uncommon to find a mix of Bermudagrass cultivars, but you don’t typically see blends containing Bermudagrass, centipedegrass, and St. Augustine grass.
Whatever you do, don’t try to get fancy and blend warm-season and cool-season grass types. You’ll likely end up with a lawn that has patches of different textures and colors.
Steps to growing your lawn from seed
Growing a new lawn from seed isn’t necessarily a complicated process — compared to solving quadratic equations — but it is time and labor-intensive. Many things, like moisture levels, soil conditions, and temperature changes can affect germination. Luckily, our blog contains tips and tricks to help you get that green and healthy lawn of your dreams.
The following quick guide will help you start a new lawn from seed.
When planting, you always want to check the seed package for the soil conditions your grass seed prefers and ensure you’re seeding at the correct time. It’s also helpful to run a soil test before planting, checking for soil pH, organic matter content, and nutrient concentrations.
When is the best time to plant grass seed?
Plant cool-season grasses in the early fall once summer temperatures have eased; plant warm-season grasses when temperatures start climbing in late spring or early summer. Make sure the soil temperatures are in the recommended planting range in all climates.
- Start with slightly moist ground. Hard, dry dirt is more difficult to work with. So, water the area two to three days before planting.
- Depending on the size of the planting area, use a garden rake or a rototiller to work the top couple of inches of soil until it is loose and friable. If your soil lacks organic matter, you can work a couple of inches of finished compost or well-aged manure into the soil. If your soil needs amendments like lime, this is the perfect time to add them.
- Level your soil with a rake or other hand tool. A flat surface allows even water penetration (versus waterlogged low spots) and is easier to mow.
- Use a broadcast spreader or a grass seeder to spread the seeds across the soil. Use the numbers on the grass seed label to spread the correct amount of seed per square feet of ground. You can spread the seed in either one of two passes.
- If you choose to see in one pass, use the seeding rate listed on the bag’s label. Walk from one side of the planting bed to the other in a zig-zag pattern. Slightly overlap the passes using a drop spreader; be careful not to overlap the passes using a broadcast spreader.
- If you’re making two passes, divide the seeding rate in half. Spread the first half of the seed, walking from one side of the lawn to the other in narrow passes, similar to how you’d mow. Be careful not to overlap. Make a second seeding pass across your lawn. If you seeded east to west the first time, this time, seed from north to south to create a crosshatch pattern. This ensures seeds are evenly spread and scattered across the planting bed.
- Once the seed is down, you need to create good seed-to-soil contact. Cover your seeds with a thin layer of topsoil by gently raking the top of the planting area. Recheck your seed package for the specified planting depth — some seeds must be buried deeper than others. You could also use a lawn roller or a tamp to press the seeds into the soil or gently walk across the ground to tamp the soil with your feet.
- Now it’s time to water! Turn on the sprinkler or use a gentle setting on your hose nozzle and soak the seeded area until the soil is damp a few inches deep. Don’t waterlog your seeds; this will drown them by pushing the oxygen out of the soil. You’re looking for dark, soft soil that feels like wet sand, but make sure the soil isn’t waterlogged.
- If you want, you can cover the planting bed with a smattering of straw or mulch to help keep the seeds moist and prevent them from being washed away. Ideally, you only want about 50% cover so plenty of sunlight still reaches the grass seed.
- Water your newly planted seeds twice to three times daily to keep the soil moist. For most people, you’ll only need to water for about five minutes each time. Watering too much increases the susceptibility of damping off or other seedling diseases.
- Wait patiently. Your seeds have an initial germination period, but some will take longer than others. This is especially true if you’re using a mix or a blend. Wait until a few weeks after planting to decide if you need to add additional seeds.
Congratulations, you’ve seeded your lawn! Keep a close eye on it, water regularly, and make sure no one walks on your delicate seeds.
Wait to mow until your grass seedlings have exceeded the recommended mowing height, and when you grab a handful and pull, it feels firmly anchored into the ground. It takes a while for the developing roots to take hold; if you mow too soon, you risk pulling your new grass right out by the roots.
Store extra seeds in the package; you can refer to it as needed and plant them in any area where germination was unsuccessful.
FAQ about grass seed
How long does it take grass seeds to germinate?
Depending on the type of grass seed, you should typically see your first shoots within 10 to 14 days of planting. Perennial ryegrass may sprout within a few days, but slower centipedegrass and Kentucky bluegrass may take up to 28 or 30 days.
Do you need to soak grass seeds before planting?
It isn’t necessary to soak grass seeds before planting them in your yard, but the process will speed up germination. You can soak your seeds in tubs or buckets for about 24 hours before planting. Soaking them starts imbibition and softening of the seed coat.
What happens if you don’t water grass seed?
Not watering your seed for an extended period significantly impacts germination and growth. The longer a seed goes without water before germinating, the longer it takes to break dormancy and begin growing. Once the seed germinates, a lack of water — even if only for a day or two — leads to a greater chance of death.
These tiny plants have minimal, immature root systems that cannot access significant soil moisture. They need consistent access to moisture and frequent watering until they develop further and grow into the soil.
Need some help with grass seed?
Whether you need help picking out the right grass seed for your lawn, planting it, or tending to the beautiful new grass as it grows, we’ve got you covered! Reach out to Lawn Love, and we’ll put you in touch with local landscaping professionals who know everything about growing the best green lawn in your area.
Main Photo Credit: John Mounsey | Pixabay | License
