Normally this is where I'd start applying corn gluten, but it is missing from our programs this year with exception of the organic package. The reason is, like most other lawn companies out there, we've become fatigued by the song-and-dance of how well this application actually works.
Take for instance last year, an anomaly I know, but the forsythia was blooming 2nd week of April. On a normal year that would be early May and the corn gluten would have to be applied prior to this event.
That said...you are looking at- if you're accurate in your application (20lbs per 1,000 sq. ft. of lawn)- an effectiveness of four to six weeks as a pre-emergent.
Even on a normal year that takes you to early/ mid June. Then we get drought and heat like we've had the past few years and Bingo everyone gets crabgrass. Cue the unhappy customers and the angry calls.
With the few products that are approved for use these days we've had to do some fancy dancing of our own.
Take for instance Nematodes. On the heels of the worst grub damage I've ever seen, you may be tempted to buy a sponge, or two to treat your battered lawn this spring.
Well- Let me just tell you what the Turf Grass Institute says about spring applications.
Grubs are up and feeding now. There isn’t a lot of grub damage per se. The secondary pests such as raccoons, skunks and starlings are doing their usual spring damage to turf that is infested with grubs. As far as control goes, there is very little that can be done this time of year. Last spring Dr. Michael Brownbridge and I conducted a spring applied nematode trial and neither Hb or Steinernema glaseri were effective. To help recovery, rake the dead areas and plan to over-seed in a couple of weeks. Whether it is home lawn turf where you are relying on insect parasitic nematodes or golf course turf where you are relying on traditional pesticide chemistry, now is not the time to control grubs. Make a note of the damaged areas and plan to apply grub control in the mid summer on golf courses or in August for home lawns.
We've also stopped buying product from any supplier whose sole purpose is to make money off people like you and I with products that do not work effectively
So go out and get your 20kg bag and apply it if you wish. Load up on Nematodes. But right now these products are dead weight I can do without.