Why was crabgrass and goosegrass so prevalent this year?
The answer is twofold…
Crabgrass controls should be applied as close to the date that crabgrass really germinates as possible. The soil temperature has to be at least 60 degrees for this to happen. Even when the surface of the soil hits the 60 degree mark, it still is many weeks more before the soil is a consistent 60 degrees or more in the top inch of the soil. Crabgrass and goosegrass will germinate in stages from about the middle of May through June. Many lawn services put down the crabgrass control to early. They do this because they have so many lawns to service that they can’t get them done all in time, before the crabgrass germinates, if they don’t start their servicing in early March. The soil temperatures at this time normally are still in the high 40′s or 50′s but certainly not warm enough for the crabgrass to germinate. By the time the crabgrass germinates, the crabgrass control is close to expended. Some crabgrass controls such as pendimethalin will only last for 10 weeks and only control crabgrass before it germinates. There are better crabgrass controls on the market today such as Dimension which lasts up to 18 weeks and will kill crabgrass both before it germinates and even after it germinates up to the three leaf stage which in the northeast usually occurs by June 1st.
In conclusion, good crabgrass and goosegrass control is all about the timing of the application, to early is not good at all and the specific crabgrass control is also very important. If you had put down Dimension Crabgrass Control this year in the middle of May, the lawns that you service would have had no crabgrass in it at all right through August and if you needed to you could still plant grass seed by mid-September. Try this approach next year…your customers will thank you for it!