Are you having trouble getting your grass seed to grow even though you have used quality seed, properly prepared your yard, and watered properly? It’s not uncommon for homeowners to be frustrated and ask “Why is my grass seed not growing?” – after all, preparing to seed your lawn and watering seed is hard work (and seed is expensive). Nothing is worse than feeling like that time and money has been wasted.
In this article, I will talk about some common problems that might explain why your grass seed is not growing, and share how to tell if your seed can be salvaged.
Let’s start with the basics.
What Grass Seed Needs to Germinate
Grass, like most plants, needs a few basic things to germinate and grow. If any one of them goes missing, seed may not germinate, or may falter and die shortly after germination.
Your grass seed needs:
- Contact with your soil,
- The right amount of moisture (consistently),
- Sunlight, and
- The right temperature.
There are more things to consider, and I’ll get into them below as part of my list of reasons why your grass seed is not growing, but if any of these most basic needs are not met, your grass seed probably won’t grow well.
Why is My Grass Seed Not Growing? (common problems)
Below I cover in detail the most common reasons why grass seed fails to grow. These include:
- Insufficient Sunlight
- Excessively Hard Soil
- Soil pH Not Right
- Cold Air and/or Soil Temperatures
- Seed was Buried too Deeply
- Herbicide Applications
- Too Much Foot Traffic
- Unnecessary Lime Application
- You Used Too Much Grass Seed
- You Used Too Little Grass Seed
- Poor Quality or Expired Seed
- Planted Your Seed at the Wrong Time of Year
- Your Seed Has a Long Germination Time (but could still be fine)
- Improper Watering (too much or too little)
Now let’s take a closer look at each of these problems to help you diagnose your grass seed issue and help you get back on the right track.
If your lawn doesn’t get enough sunlight each day, this may lead to problems with grass growth. A bare minimum of one to two hours of strong sunlight per day is usually necessary.
If you have shady areas, choose a type of grass seed that is known to grow well in those kinds of conditions.
There are grass seed mixtures on the market that may be appropriate. Grass seed needs sunlight in order for photosynthesis to occur, which is how it gets its energy to grow beyond its seedling leaves.
Excessively Hard Soil
If your soil is hard, compacted, or has a high clay content, then this could be another reason why your grass seed is not growing. It’s important to properly prepare the soil before planting seed. This generally includes getting rid of any thatch or dead grass, thoroughly raking the soil, and getting rid of debris.
If you have a large property and this would be an overwhelming amount of work, think about renting a special motorized machine for the task. Hard soil is often compacted soil. Compaction occurs as a result of heavy traffic and the soil not getting the water it needs.
Seeds cannot germinate in compacted soil because they lack access to air and without respiration, they cannot break down the store of energy they have within them.
This is where core aeration can really benefit your lawn and help your grass seeding project deliver perfect results.
You Didn’t Test the Soil
Soil with a pH of less than 6.0 can also cause problems with growing and establishing grass seed. It’s best to do proper soil testing before planting your grass seed. Ideally, the test should be processed by a professional soil laboratory. I use this one you can order from Amazon every spring to give me information about where my yard’s soil is, what it needs (and what it doesn’t).
The test results will tell you what your soil has and lacks, and what you need to do (and shouldn’t do) before and while planting.
This is important, as sometimes adding fertilizers and other kinds of soil amendments that aren’t needed can cause problems rather than give your soil the helping hand you intended.
It will also tell you if your soil pH is appropriate, or if you should be amending with Lime or Sulfur to get the balance ideal for grass.
Best Overall Lawn Soil Test Kit
The Soil Test Kit I Use & Recommend
There are many options for testing your lawn’s soil, but I prefer a lab-based soil test that provides a detailed analysis of your soil’s nutrients and what’s needed for your lawn to thrive.
I use this one from MySoil every year.
And if you’re interested in taking the guesswork out of what to do next after you get your soil test results, consider Sunday’s subscription lawn-care plan. They test your soil for you and use local weather data to send you exactly what your lawn needs, when it needs it. It’s pretty fool-proof – you can Click Here for Your Instant Lawn Analysis and take 12% off your order with promo code LAWNCHICK2023.
Cold Air and Soil Temperatures
Depending on the type of grass seed you use, cooler air and soil temperatures can also cause problems with germination.
Most varieties of grass seed require soil temperatures at least above 55 degrees Fahrenheit.
That being said, some grass seed types prefer even warmer soil temperatures.
If it’s too cold for germination, your seed may still germinate when the soil temperatures rise – the risk is that if it’s wet and in the ground for too long before it does germinate your seed could rot.
Seed Buried too Deep
Remember to follow the instructions provided on the label of your grass seed when planting.
You need to avoid planting it too deep or too shallow. There needs to be just enough surface area contact between the seed and the soil for your new seedlings to germinate and thrive.
Many novices plant their seed too deep, thinking they’re helping. But as long as you loosen the soil a bit beforehand, most grass seed will grow if spread right on top of the ground and covered lightly with some kind of mulch to protect it and keep it moist.
Use of Weed Control Products
If you have applied weed control products of any kind, then they could be the reason why your grass seed is not growing. Remember that one mechanism pre-emergent weed control treatments use in your lawn is that they stop weed seeds from germinating. Many can block germination of grass seed as well.
Generally speaking, you shouldn’t use any kind of pre-emergent weed treatment for a minimum of 10 to 12 weeks before you plant your grass seed. An exception is this one, which I’ve personally used when reseeding and overseeding my lawn in the spring and it does not block grass seed germination.
This is why it’s so important for you to read the labels and instructions on weed control products, even some of the best weed and feed products can block grass seed germination.
Failing to Keep Traffic Off Area
It’s important to avoid traffic being on areas that are newly seeded. Obviously you don’t want to drive your car (or even your lawn tractor) across the lawn in the early stages of growth, but even foot traffic from you, kids, or dogs can do a number on your seedlings.
Try to keep everyone off your new lawn until the grass seems to be established. Once you find it’s appropriate to mow the new grass, you can walk gingerly across it, but I recommend that you should mow a couple of times before you allow normal foot and pet traffic.
You Applied Unnecessary Lime
Contrary to popular belief, it’s not always necessary to apply lime. I have an in-depth article about how to tell if your lawn needs lime, but to be brief: lime applications are needed only when your soil needs a higher pH.
If you apply lime on soil that already has a high pH, this could cause problems for your lawn, including poor germination and seedling performance.
You Used Too Much Grass Seed
Yes, it’s possible to use too much grass seed when planting a new lawn.
This is because an excessive amount of seed can lead to unnecessary competition for resources, including nutrients, light, and water.
Generally, your seed should still germinate, but it may fail to thrive. I like to go heavy on my seed (about 1.5x the manufacturer’s recommendation) when seeding a new lawn, but it’s important not to go overboard or you can stunt the growth of your entire new lawn.
You Used Too Little Seed
Of course, it’s also possible that you used too little seed. If this is the case, you will notice that some areas of your lawn are bare, patchy, or thin.
One reason why it’s so important to properly measure your lawn is because if you apply too much or too little grass seed, it will lead to issues for you. The same goes for fertilizer, pre-emergent, and other products.
Choose High Quality Seed
Look for a decent level of quality when buying grass seed, and make sure to check the date on the package to be sure that you’re not getting old or expired seed.
Take a close look and learn about the seed tags found on grass seed products. It’s a good idea to avoid choosing the least expensive variety of seed you find, and I also recommend that you watch out for the word “annual” on the package. Annual grass seed will grow great the first year, then die off and leave a perfect place for weeds to take root the following year, so make sure every seed in your mix is perennial.
Inexpensive seed products are more likely to contain fillers (as opposed to seed), old seeds that are no longer as responsive as they would have been earlier on (you’ll get a lower germination rate), a greater number of weed seeds (these will be green and grow well, but it is definitely not what you want), and lower germination rates overall.
Your effort to prepare the site and care for your seed up to and in the weeks following germination will be the biggest factor in your seeding success or failure, but seed quality is a close second.
It’s worth the money to buy better seed.
Plant Your Grass Seed at the Right Time of Year
Remember that grass grows in seasonal cycles. You must plant your seed at the correct time to make sure the growth will work with the growing cycles.
It’s usually best to avoid planting grass seed in spring when your young seedlings will have to compete with annual weed pressure and the taxing heat and drought of summer.
The exception is if you live in the south – late spring is the best time of year to seed your warm season grasses, as their natural growth season is during the summer and this timing will help them get established when they grow best.
In northern climates you’ll be fighting a losing battle if you try to plant a new lawn in the summer.
Remember the Species
Keep in mind that different species of grass seed have different germination times. This means that every type of grass varies in how long it takes to start growing.
One of the slowest species (but also the best for lawns) is Kentucky Bluegrass. It can take almost a full month for Kentucky Bluegrass seed to germinate … so if you’re wondering “Why is my grass seed not growing?” … it could be that it’s just a seed that takes longer to germinate and show signs of growth. You may just have to be patient!
If you’re looking for an especially quick germinating grass species, think about Perennial Ryegrass if it suits your climate and needs. It will often take only 5-7 days to germinate. Barenbrug has a good Ryegrass seed.
Too Much or Too Little Water
In order for your grass seed to thrive, you must give it the appropriate amount of water. Either too much or too little (or watering your grass seed at the wrong time) will quickly lead to problems.
An excessive amount of water can prevent proper germination or wash the seeds away entirely. This is why trying to plant grass seed during the spring when it’s raining a lot can lead to poor results. Too much water can drown the seeds. When this happens, they will end up floating up to the surface, being pulled out of the soil, or washing to low spots in your yard (or worse, down the storm drain).
Water your newly seeded lawn enough so that it is moist all the time, but don’t give it so much water that there’s a danger of drowning it.
The most important phase in grass growth is the one before you can see the sign of sprouts. Be especially careful during that time that you’re watering appropriately. Your seeds must stay moist (but not soaking wet) during this time.
Seeds May Sprout at Different Times
Be aware that the grass seed you planted probably won’t sprout all at once. This is because seeds tend to be buried at slightly different depths, may be of differing maturity or quality, and may be different in how they absorb water.
Additionally, many homeowners use a blended seed which includes seed for different species of grass. Each one will have its own growth track. Some seed (like Ryegrass) may germinate quickly, others (like Kentucky Blue) may take several additional weeks to germinate and begin to establish.
If you used a blend of grass seed and your lawn looks super-thin when seedlings first start to emerge, don’t panic. This is probably what’s going on for you.
If you choose to plant a seed mixture (as opposed to all just one species), you can expect the seeds to have different characteristics, especially in the arly days. That’s normal, and actually a desirable quality in a lawn once all of your new grass matures.
Having a mix of grasses that grow differently can help with the appearance of your lawn throughout the year. When one grass type struggles in conditions present in one area of your lawn, another may thrive, and you’ll have a more consistent lawn overall.
Solutions for Why Your Grass Seed is Not Growing
Noticing that your new lawn seems to be sprouting slowly isn’t always a cause for serious concern.
Hopefully, this article has helped you learn about a variety of reasons why germination may be happening more slowly than you expected. With this information you should be able to narrow down the cause of your issue and (hopefully) address it and have success going forward.
If you’ve used a seed that is known for long germination times, or you buried your seed a little too deep – don’t despair! It might come up, just a little slower than you expected.