Question
I started a new lawn from seed about 8 weeks ago. I've mowed it about 6-8 times. The grass is good in the shady areas, but in the full sun part, it,s getting over-run w/ crabgrass... Help!?

Answer
Grassplant is an annual plant which will die with first frost. Before it dies it will set seeds. In early spring, put fertilizer w/crabgrass preventer (such as Scott's Turfbuilder w/Halts). The herbicide will prevent seeds from germinating (including crabgrass seeds). The fertilizer mix must be put down in early spring just as the forsythia blooms. If soil temperatures stay above 55F for more than a week, the seeds germinate. once they have sprouted, you can not control them with this product, so it must be put down early enough (but not too early or it will not work). Generally soil stays cooler than air in spring. If in doubt, ask a local garden center or your local county extension office when it is right to apply the fertilizer.

You can also buy liquid spray bottles of post-emergent crabgrass killer which is sprayed on young plants (less effective on mature plants). It may temporarily discolor your grass. This is your best choice in summer, but you can also wait until next year and use the pre-emergent herbicide instead - or you can do both.