Whether you are filling in patchy spots, overseeding or starting a new lawn you may be wondering how long it takes grass to grow from seed. In today’s post we are going to walk you through the entire process and help you to understand why the answer is not so simple.
How fast it takes your grass to grow from seed will depend on a few key factors, which include:
- Grass types
- Growing region
- Growing conditions
In general, most grass types will typically grow from the seed in one to four weeks, or 7-28 days.Kyle @ The Backyard Master
Figuring out how long it will take for your grass to grow from seed can be really important because once you determine how long it will take, you can start to plan around that and set up a general schedule for your grass.
The germination period is probably the most important phase for growing grass, so we’ll continue to discuss how to determine how long it will take for your grass to initially sprout from its seed and give some examples of certain types of grass.
Types of Grass That You’re Growing
As we mentioned before, the biggest factor when it comes to how long your grass will take to grow from seed is the type of grass that you’re planning to grow.
As you probably already know, there are many different types of grass, and each of them has its own recommended method of growth and conditioning.
Many people may think that growing grass is pretty simple, but it’s actually quite complicated, and most of the time, it will require a lot of planning beforehand.
Come to think about it…growing grass from seed is a lot like parenthood. You think it will be easy, but once you get started you realize you have no idea what you’re doing. Ha!
Grass Climate Type
The most general way to categorize the different types of grass is to base them off on their preferred climate conditions:
- Warm-climate grass seeds
- Cold-climate grass seeds
- Transition Zone-climate grass seeds
As you might guess, the different seed types correspond to what kind of climate or weather where they should be grown, and the Transition Zone is where, within reason, you can plant either warm or cool season grasses.
Even though it may seem obvious, it’s very important to know and keep track of what kind of grass you’re growing because the variety has the biggest effect on how long it will take for your grass to grow.
Now that we know that grass seed is typically classified by climate type, we can begin to discuss the actual specific types of grass that many people use.
Many people would be surprised to learn how many different types of grass there are, and there are definitely a lot, but we’re going to focus on a few popular ones separated by their climate type.
- Perennial or Annual Ryegrass – Annual Ryegrass grows very quickly compared to other grass types, taking about 5 to 10 days to grow from the seed, and it can be used in a lot of situations for season erosion control or winter overseeding of bermuda lawns for winter green.
- Bermuda Bluegrass – Bermuda grass seed takes a little bit longer to grow, taking anywhere from 10 to 21 days.
- Zoysia Grass – The Zoysia grass variety takes the longest to grow from seed, taking about 14 to 21 days to grow.
- Kentucky Bluegrass- Kentucky Bluegrass is the most popular of the cool season grasses. It is a slower growing grass and will take 14-28 days for germination.
- Bentgrass – A cold old-climate grass, and it typically grows within 14 days.
- Perennial Ryegrass – The Perennial Ryegrass is a popular grass and has a very quick germination rate. It takes a lot of watering and care, but it’s very quick to grow, only taking about five to seven days.
- Turf Type Tall Fescue – Turf Type Tall Fescue has a germination time between 7-21 days.
Transition Zone Grasses
As mentioned above the these grasses are likely to do well if you live in the U.S. transition zone as opposed to the clear cool zone of the north or warm zone of the south.
- Bermuda Grass
- Turf Type Tall Fescue
- Kentucky Bluegrass
One last factor that you need to keep track of is how old your actual grass seeds are.
This is very important because this can greatly affect how long it will take for your grass to grow from seed and, depending on the severity of its age, whether your grass will actually be able to grow in general.
Grass shelf life is typically around two years, and the older the seeds are, the harder it becomes for them to grow.
When they pass their expiration date, they won’t even grow at all, so you need to keep track of this important information.
What often happens is that people will buy big bags of grass seed from stores and assume that they’re fine and ready. I’ve been guilty of this myself.
Another concern is that plenty of stores will keep very old grass seeds on their shelves, so you need to do is check the expiration date.
If you aren’t sure what the expiration date is on seeds that you already have, a good way to check if they will grow is to place them on a damp tissue inside a plastic bag; if the seeds haven’t expired, you should be able to see them sprouting in a few days.
Knowing where and how you plan to grow your grass is just as important as knowing the type of grass you’re going to grow because each factor will affect the other one. Once you know what kind of grass you plan to grow, you can start to prepare to create ideal growing conditions and vice versa.
Keeping track of your growing conditions will help you answer these important questions:
- Where will you plant your grass?
- How will you plant your grass?
- When will you plant your grass?
As you might guess, your local climate is going to have the biggest impact on how fast (or slow) your grass grows.
When evaluating your local climate you want to consider:
- Light exposure
- Precipitation patterns
- Soil Temperature
The other growth factor that is probably more important than the grass itself is your soil.
In most cases, you probably even want to figure out what type of soil you’re going to use or that you have available before you choose they type of seed you plan to use.
In addition to the type of soil you have you are going to want to track:
- Soil temperature
- Soil humidity
The general guideline is that your soil should be around 55 degrees Fahrenheit for cool season grasses and 65 degrees for warm season grasses, but keep in mind that different grasses grow at different rates.
As far as the humidity is concerned, you just want to make sure that it’s not too dry or too wet. This is typically going to be between 10-45% moisture, which you can measure with a hygrometer.
Besides those two factors, you also want to make sure that you’re planting your seeds at a good depth in the soil, and that will depend on your grass type and the specifics will be including on the packaging for you.
Grass has its peak growth period at certain times of the year, and this will depend on what type of grass you’re growing and your location.
To keep things simple, it basically comes down to what type of climate your grass is best for, and then you can start growing your seeds during certain seasons.
For example, warm-climate grasses are best to start growing in the spring, and cold-climate grasses grow best in the fall.
Again that’s very generalized, and it will depend on your specific situation, but the idea is that you should track when it’s best to start growing your grass so that it grows in the best way possible.
Today we wanted to help you discover how long it will take for grass to grow from seed, and as you can see this is not a “one size fits all” situation.
Hopefully, you’ve learned that the exact amount of time it’s going to take your grass to grow will depend on the type of grass you plan to grow and where you plan to grow it.
It’s important to realize that once grass seed has sprouted you’re not finished; this is only the beginning.
From there, you need to monitor it regularly, and in most cases, you need to keep watering and treating it.
As a general rule of thumb, your grass will take anywhere from a week to a month to grow, if you’re using high quality seed and it has access to optimal growing conditions.
Growing Grass From Seed FAQ’s
How often do you need to water new grass seed?
(click the link above to view our detailed post on watering new grass seed)
When you are growing grass from seed it is important to keep the seed consistently moist.
Doing so will depend on the outside temperature and your soil’s ability to maintain moisture. This is best accomplished by short, infrequent waterings (just to the point before puddles appear).
In most scenarios it is best when you water 3 to 5 times a day for 5 to 8 minutes a time. Once germination is complete you can back off of the watering to once a day and then to once every other day.
How do I speed up grass seed germination?
The best way to ensure speedy germination is to sow your seeds at the right time and ensure adequate moisture to the seeds and the soil.
Providing your seeds with a light layer of peat moss will help with moisture retention as well as the application of a starter fertilizer will help with good germination.
Unfortunately there are no tried and tested methods to actually increase the germination rate of seed. That is left up to Mother Nature. Trying to speed up the process of the seed germinating beyond what is typical is like saying, “How can I have my baby sooner?”
What type of grass seed grows the fastest?
The fastest seed to germinate and establish if Perennial Ryegrass. This grass is great for cooler climates so if you need a lawn quick consider Perennial Rye.
How long after planting grass seed can you walk on it?
Minimal walking on the lawn is ok as soon as your seeds are planted.
Don’t be afraid if you need to get onto the newly seeded lawn to move sprinklers or hoses. Just make sure you are not dragging your feet or the hoses across the lawn as this may move or disrupt the seed.
It is also best to not have your pets (or kids) on a newly planted lawn until you have mowed it at least twice. At that point it’s a bit more established and hardy.
Watch a time lapse of a new lawn growing from seed.