Question
I live outside of Syracuse, NY and have a question on new grass.  I planted some new seed approx 3 weeks ago in some good soil and it seems to be growing quite well.  There are some weeds and crab grass coming in with it.  I want to "weed and feed" but I'm not sure if it's to premature.  I would appreciate your feedback.

Answer
I worry about my choice of answers here, my friend.  No one in our part of the country should be planting Grass seed in July.  Baby Grass is not equipped in a normal Summer to grow big and strong, into the kind of Grass you can make a great Lawn out of.

Missouri's Dept of Natural Resources posts a fact sheet on 'Cool Season Grass Land Management...'  It sheds some light on how and why we don't plant Grass this time of year.

They point out: 'Cool Season Grasses achieve maximum growth and development from March to June and again from September to November ... Most Cool Season Grasses have relatively shallow root systems that are unable to tap moisture deep in the soil.  During extended dry spells, leaves of Cool Season Grasses stop photosynthesizing, turn brown and die to reduce water loss.  This dormancy allows many species of Cool Season Grasses to survive drought conditions.'

You can read the whole speech here:

http://www.p2pays.org/ref/15/14912.pdf

Their report on 'Cool-Season Grass Seeds' by Univ. of Minnesota Dept of Agronomy and Cooperative Extension Service, University of Wisconsin at Madison, guides Sod farmers on great ways to make Grass seed, including progressive Weed control techniques:

http://corn.agronomy.wisc.edu/AlternativeCrops/CoolSeasonGrass.htm

They point out, 'It is important to have adequate Soil moisture and Soil temperatures for germination and establishment.  Cool-season grasses may be planted either in the spring or late summer.'

Grass germinates optimally when the Soil temp is 40 to 45 degrees F, they maintain. And if you're wondering what they'd say about those Weeds and Crabgrass encroaching on your new Lawn, they advise that if 'Weed competition is anticipated, seed in late summer and control Weeds by tillage and/or chemical methods prior to seeding.'

Critical factors include soil moisture and a healthy grace period for adequate growth before the first frost.  Strong Grass will out-grow Weeds in a heartbeat.  Trouble is, you have BABY Grass -- not STRONG Grass.  And on top of that, you are putting the BABY Grass head to head with THRIVING Weeds that LOVE heat and experience their fastest growth at this time of year.  Unlike Cool Season Grass, which is enjoying Siesta Time.

No wonder you are looking at a Weed Problem.

You should know that Mowing is one of the best things you can do for a new Lawn.  'Mowing is an excellent option and provides good Weed control when done in a timely manner. Mowing also promotes newly seeded grass plants to tiller and produce sturdier plants.'

Weed and Feed applications in my book are never an option -- indiscriminate application of Weedkillers are considered bad turfgrass practice.  Feeding your new Grass concentrated fertilizer brings us to the matter of metabolism and overfeeding.  Your new Grass needs a root boost.  You don't get that from Nitrogen -- the big vitamin in most Grass fertilizers.  If your soil is rich and healthy, you don't need ANY fertilizer -- just a dose of slow-speed, gently released nutrients made by microbes.  Any Weed and Feed will wipe out the microbes.

Sorry to take so long to explain all this.  I guess I was trying to look at the Sunny Side and could not find one.

At this point, I would say you should watch your Grass carefully, and Mow frequently to keep the Grass Weed-free and deep-rooted.  But something tells me you will Weed/Feed regardless.  Like they say, you can lead a horse to water...

I hope you succeed with this early project.  If not, try again this spring, or perhaps even fall.  Good luck, and thanks for writing.