Should I plant grass seed now? Johnson County lawn and garden experts give tips for dealing with March cold snap

Grass and grass seed are probably fine with the cold snap coming up. If you've already planted new grass seed, it will just take longer to germinate, but this week's expected snow is welcome after a relatively dry winter, say local experts. Here are some tips to protect any newly-planted flowers this spring.

This is typically the time of year when homeowners and weekend green thumbs start to think of their lawns and gardens.

But a new round of snow this week, along with single-digit temperature forecasts, could make spring prep a bit more complicated.

The Post talked to local experts with the Johnson County Extension Office as well as Family Tree Nursery about how homeowners can prepare their grass and protect their plants during this current cold snap.

“We’re kind of in what gardeners… call ‘fake spring’ now,” said Dennis Patton, horticulture agent with the Johnson County K-State Extension Office. “We got psyched out last week with the 70-degree weather and got the blood pumping, but this usually happens. And this whole winter has been a rollercoaster winter.”

For what it’s worthy, Patton said, freezing temperatures later in the spring — around the end of March or beginning of April, after flowers start blooming — are more concerning for gardeners that right now.

Here are some tips.

Protect your newly planted flowers and other plants

While it’s still early in the season, the experts we talked said you still should be planting.

Anyone who has already planted flowers and done other gardening should cover up their plants this week when temperatures fall because freezes can kill flowers that have started to bloom.

“Certainly, we’re as excited about spring as anybody else, but just remember, anything can happen until May 10,” said Jesse Nelson with Family Tree Nursery. “All it takes is one cold snap to really knock all the blooms off your plants. It could stunt them, or cause them not to grow in the summer.

“Don’t get ahead of yourself and have one nice week, go plant your entire landscape, and then a week later, it goes back down into the 30s and you’re digging everything up.”

If you have planted already, try these tips:

  • Cover flowers and plants with a bucket or mulch made with leaves
  • Drape a blanket over stakes above the flowers and plants so the blanket doesn’t crush the new growth
  • Bring containers of flowers and plants indoors in an unheated area, like the garage

Plants that have been out and exposed to cold temperatures all winter should be fine, even with the cold snap, Patton said.

Leave grass and new grass seed alone

Some lawns may be starting to turn a little green for the spring. Even with the up-and-down temperatures, mature grass and grass seed should be fine.

“At this point, the lawns are still pretty dormant, and the cold is not going to hurt the grass in any way,” Nelson said, noting that homeowners can begin applying “pre-emergent” solutions soon.

These product prevent crabgrass and other weeds that germinate in the spring from taking root.

Avoid watering plants and lawns until temps warm up

It’s better to water plants and the lawn after temperatures climb above freezing at night.

Watering plants and lawns while temperatures are below freezing could be hard on your hose and watering system.

Patton does recommend giving your plants and lawn a good watering when the conditions are right because this past winter was dry.

“I think the biggest concern we have is it’s just so darn dry, because we’re now in the beginning of drought conditions,” Patton said. “Plants are just less hardy, less resilient, when they’re also cold and dry.”

Nelson agreed, noting the recent snows (and potential snowfall coming Thursday) will add moisture to the ground.

It’s best to plant grass seed in the fall

Regardless, the best time to plant grass in this part of the country is actually in September and October because it gives grass seed time to get established before going through the harsh winter and being exposed to extreme cold temperatures.

The next best time to plant new grass seed is around this time of year.

In that case, Patton recommends planting grass seed early because the grass needs time to mature before being exposed to harsh, hot summer conditions.