Bethesda seed and weed schedule for established lawn
Hello, I usually seed in April and fertilize in Fall on an established lawn (partial sun and shade) but this Spring there are more weeds than average with a lot of Hairy bittercress. Is it reasonable to use a weed control agent and how soon after application can I let the dog on the lawn? How long after weeding can I seed or should I seed now and apply weed-control/fertilizer later in Spring. These are pretty basic questions but I don't see a guide online. thanks, Al p.s. if you make public, please don't include email address - I get enough spam already!
The best time to renovate or overseed your lawn is in late summer into fall. It's the best time for fertilizer too.
We don't recommend a chemical control for hairy bittercress now. It is what is termed a winter annual which got started and grew through the winter and is just now blooming, ripening seed and will then disappear. If you can pull or mow before or while it is blooming, you may have less viable seed next year.
Here is our page about hairy bittercress and how to control it.: http://extension.umd.edu/hgic/topics/hairy-bittercress
As far as lawn management, take a look at this section and it's associated links from our website. It has everything you need: https://extension.umd.edu/hgic/topics/lawns
If you have a problem with crabgrass, now would be the time to put down a crabgrass preemergent. Find one that doesn't contain fertilizer too.
More here: https://extension.umd.edu/hgic/topics/crabgrass
As far as your dog goes, read and follow label instructions on any chemical you use.