Schedule for over seeding, weed control, and fertilizing

[Ban Bot]

I am pretty new to lawn care.

We live north of Seattle. Last year I killed off the front "lawn" aka a moss and weed jungle with almost Zero grass. We brought in 13 yards of top soil and planted a North West Blend. The front side lawn was planted in ~ June (we had to replace our water line) and planted the front yard the last week of August. The side strip is thick and healthy, the front yard a little more spotty but MUCH better than last year.

On 4/3 I sprayed some Weed B Gone with Crabgrass control. This past weekend when we weeded the garden to prep planting I also hand pulled weeds.

I know the ideal time to over seed is fall but have year 2 over seedings, on in early spring once day time temps are 65, is ok as an additional.

So now I am kind of loss on the order of operation. I know I cannot over seed until the beginning of May.

But what order should I be doing over seeding, weed control, and fertilizing?

And how do I find the "right" fertilizer? Sounds like I want something ~ 21-3-3 for NPK but I see all kinds of contradictory or different advice (e.g.). Sound about right? How many times should I fertilize (4?), and when in relation to over seeding and weed control?

 

[mindless1]

Some proofreading is in order. Your sentence starting with "I know the ideal time" makes no sense.

Don't "over" seed unless you're just anxious and don't mind wasting money. Seed or don't seed. The order is as follows:

If you don't have dense enough grass you seed the whole thing. If you have bare patches alone you seed only those. When you do that, is either before some rainy days so it gets the water it needs, or if it's on a slope, not before really heavy rain so it doesn't wash away. Some people with sloped lawns prefer that it not rain so they have more control over watering rain to prevent washing away.

Otherwise it can be done at any time but if it gets too cold at night it won't germinate till it's warmer, but you're probably past that time of year by now, and if it doesn't rain enough you have to water to get germination and support early growth while roots are shallow.

When to fertilize depends on what state the soil was in, as does the NPK ratio. Generally you don't want to be trudging around with feet or a fertilizer spreader on newly sprouted grass. Wait a few weeks, say 4 or more after you have all the sprouting you accept and have given up on the rest of the seed sprouting. If your soil was low in nitrogen then it can make sense to fertilize a few days before seeding, so long as there's no problematic weed killer in it.

Read the instructions on your weed control product to determine the timing for it, how long after application you should wait to seed, if there is a wait at all. When you use something like a northwest BLEND, you'll have to determine what is in it to know if the weed formula works against it, if a wait is needed between application of weedkiller and seeding. If that's the case you want the weed killer out over 2 months before seeding, or to pick a more compatible weed killer formula for the grass type you choose.

Generic instruction for what fertilizer ratio to use is pointless. It should be high in nitrogen, but you'd have to get a soil analysis done to get an accurate ratio, and also consider your habits. For example if you don't bag grass when you mow, that cuts your supplemental nitrogen need in half if not more. Most fertilizer recommendations, even those that state not to over fertilize in contrast to their recommendations, STILL end up recommending far more fertilizer than is usually needed if you don't bag grass when you mow. More important is to keep weeds at bay.

Often your local co-op website or physical branch can provide region specific information about watering as it pertains to weather, grass types, fertilizer and more. http://pubs.wpdev.cahnrs.wsu.edu/pubs/fs200e/ Call or email them for more than a generic suggestion, not the state office but rather the one most local to you.

There seems to be some odd laws up there too, well instead of odd I should write overly restrictive when the problem only applies to certain situations instead of the other way around. For example the restriction on phosphorus fertilizer -
http://pubs.wpdev.cahnrs.wsu.edu/pubs/fs058e/