NJ Lawns Community

Hey everyone, I've been reading a ton about overseeding KBG and everyone keeps saying 'wait until forsythia blooms' or 'when soil temps reach 50 degrees' but nobody gives actual numbers! I'm in Rutherford and want to know the specific soil temperature range I should be aiming for before I seed my front lawn. Can anyone who's actually measured it give me some real numbers? Thanks!

Great question. I always use a soil thermometer for my customers in Hackensack and Paramus areas. You're looking at 50-65°F for KBG germination. I personally like to see it consistently around 55-60°F before I start seeding - that's when I get the best results. Anything below 50 and you're just wasting seed. The forsythia indicator works but it's more like 55°F when they bloom, so if you see those yellow flowers you're probably good to go.

I disagree with waiting that warm honestly. I've had success overseeding KBG in my yard in Englewood when soil temps hit 48-50°F. The germination takes longer but the grass that does come up seems stronger because it establishs before the summer weeds really kick in. I use a cheap thermometer from Amazon though so take that for what it's worth. My $.02: don't stress about hitting exactly 55, 50 is fine.

As someone who does this professionally, the 50-65°F range is correct but there's more nuance. The ideal is actually 55-62°F for rapid germination - we're talking 14-21 days at that temp vs 21-28 days at 50. I'm also running soil tests for clients and recommend getting pH in check too - KBG likes 6.0-7.0. If your pH is off, temp doesn't matter as much. Stop by Rutgerscoop in Rutherford, they test soil for cheap.

Following this because I'm in Teaneck and same question! Last year I seeded too early when soil was only about 45 and it literally did nothing - had to redo everything in September. This year I'm going to wait and get a thermometer for sure. Does anyone know if the digital ones from Harbor Freight work okay or should I spend the money on a decent one?

Thanks all! This is really helpful. So TL;DR - wait for soil to hit 50-55°F minimum, ideally closer to 55-60 for faster germination. I'll grab a thermometer from Garden State Garden Center in Rutherford. One more question - do you guys measure at 2 inches deep or surface level?