Pre-emergent question

Bermuda, St. Augustine, Zoysia, Centipede, Bahia, Paspalum, etc
Post Reply
User avatar
Posts: 107
Joined: May 22nd, 2010, 3:39 pm
Location: Prosper, TX
Grass Type: Hybrid Bermuda
Lawn Size: 5000-10000
Level: Experienced

Pre-emergent question

Post by jtyrie » February 7th, 2020, 6:25 pm

I know that pre-emergent should be put down in the spring when the soil temperature reaches 55. I live in the Dallas - Fort Worth metroplex and the local gardening guru says to put it down between March 5 - 15. I've been following that date for a long time and have been less than satisfied with the results. The problem with our area is that it will often get really warm in February for a few days and then cool back off and become more winterlike. It causes all kinds of confusion with the spring bulbs, etc. I believe it also causes some weeds and unwanted grasses to germinate early. I'm thinking that I may treat the lawn twice this spring. The first treatment around Feb 15 and then the second one in the traditional March period. My question, am I going to harm anything (other than my wallet) by doubling the treatment so close together? I feel that with the two treatments, I'll have a better chance for good results. I'd appreciate any advice or discussion on this.

User avatar
Posts: 3180
Joined: December 17th, 2008, 1:53 am
Location: Bandera, Texas
Grass Type: St Augustine
Lawn Size: 5000-10000
Level: Advanced

Re: Pre-emergent question

Post by Dchall_San_Antonio » February 12th, 2020, 4:20 pm

I know that pre-emergent should be put down in the spring when the soil temperature reaches 55.
I believe that is wrong advice. I believer spring rainfall is a better timing indicator than soil temp. For example you likely just got a day of mist, a day of drizzle, and a night of rainstorms. NOW IS THE TIME, to apply preemergent. TODAY! Why? Because weed seeds need several days of moisture to germinate and take root. If you wait for the weekend, some will have already germinated. Later in the spring you'll get another multi day rain event. Reapply preemergent then, too.

These summer annual weeds are not to be confused with wild flowers and the spring annual weeds. Those plant seeds germinated last fall during the rain event in August and/or October. Those plants germinate and immediately go dormant. Then during these spring rain events, the dormant plants/weeds bolt and become flowers.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest