How To Protect Grass Seed From Heavy Rain

Rainy days are a boon for any plant-loving homeowner. They help lower your water bills by providing additional moisture for gardens and lawns and save you the time you would have spent breaking out the sprinklers.

However, heavy rain can also harm your newly planted grass. Here’s what you need to know about how to protect grass seed from heavy rain.

Is Too Much Rain Bad for Grass Seed?

Choose your planting season carefully. Constant, heavy rain after planting grass can undo all of your hard work.

Newly planted seeds need a lot of moisture to germinate, so a bit of light rain won’t kill them. However, a flooded lawn can negatively affect the germination rate and drown your seeds.

You should also watch out for soil erosion. Until your seeds germinate and form strong roots, downpours can wash them away.

Seed Germination Time

The act of sowing seeds might be relatively easy, but keeping them in place until they successfully germinate comes with more challenges.

Depending on the type of grass, germination time can take between five days and a month. Several factors, including temperature, sun exposure, humidity, and seed age, affect this rate.

Take extra care of your lawn during this growing stage.

How to Keep Seed from Washing Away

Even if you plant your seeds in the optimal season, not every day comes with perfectly moist conditions. You can follow the tips below to protect your grass from flooding and erosion.

Lawn Aeration

Compacted soil makes it harder for water to drain correctly, leading to flooding and pooling.

Properly aerating your soil doesn’t just help protect your seeds from rainfall. It also improves overall grass growth. This process allows air, water, and nutrients to reach your plants, leading to healthy root growth.

Loosen your soil with a pitchfork or rake by poking three-inch holes throughout your lawn. For dense soil, you might need to use a tiller or an aerator machine.

Change Your Soil Composition

The best lawns use loam soil because it can hold moisture and drain well if flooding occurs. It also retains nutrients and allows sufficient airflow.

Loam soil has three main components:

  • Sand has the biggest particle size. It drains well, warms up quickly, and is easy to cultivate.
  • Silt has medium-sized particles to promote water and air retention.
  • Clay has the smallest particle size. It’s sticky when wet, retains a lot of water and contains plenty of nutrients.

Clay-heavy loam soils might create a problem during heavy rains. You can add sand or silt to improve the layer for where you’ll be sowing your seeds.

Clean Your Gutters

Drainage systems require proper maintenance to function correctly. If you have clogged drains or gutters near your lawn, they may cause water buildup. Clear them of leaves and other debris to ensure that doesn’t happen.

Level Your Lawn

Your lawn slope determines how and where water drains, making it the most critical factor to prevent flooding and pooling.

You can add soil to low-lying areas to make your lawn as level as possible. However, properties with extreme sloping might require other solutions, like a new drainage system.

Install Adequate Drainage

A long-term fix for persistent flooding is to install new drainage for your lawn. If your yard sits in a low lying area, a drainage system can divert accumulated water to another location.

Installing one may take time and money, but it’s worth it if you live in an area prone to rain. Standard drainage systems include:


Swales are depressions that guide excess water to a particular area. The bottom has a lining made from deep-rooted plants and rocks to slow the flow of water.

French Drain

French drains are an excellent option if you don’t want a drastic change to your lawn’s appearance. It’s essentially an underground creek, with a drainpipe under the soil that diverts the water to other areas.

Sump Pump System

Sump pumps are electric devices that pump away accumulated water. While this solution is more effective at preventing flooding than a French drain or swale, it’s also more expensive and requires additional maintenance.

Use Protective Covering


Many options are available for covering grass seed. However, many homeowners prefer using mulch because it’s cheap, eco-friendly, and effective.

A light mulch covering protects your seeds from hungry birds, rainy weather, and colder temperatures while still allowing moisture, sunlight, and air to reach your seeds. It can also improve soil quality by providing nutrients once fully decomposed.

A word of caution, though. Mulch may contain weed seeds that can quickly spread throughout your lawn, so use a weed-free version if you can. When using mulch, apply just enough until the soil below is slightly visible.


Another natural covering you can use is straw. You can purchase some in the form of “erosion blankets” that are specifically built to protect your plants from harsh weather.

Like mulch, straw decomposes after some time and leaves nutrients for the soil.


You can purchase fabric rolls at home improvement stores and garden centers to cover your grass seeds.

When using these covers, lay them over the planted seeds and tack them down at the corners using tent spikes.

If you have a sloped lawn, you can bury the edge of the covers at the top portion of the slope under a few inches of dirt to prevent water from running underneath them.