Question
First I want to say that I am so excited by all the information that you provide. I can't wait to be organic.

I have several questions:
How do I know if my lawn is going to seed?
How do I know if the weeds are going to seed?
If I have to mow higher to strengthen the grass and reduce weeds, and the weeds are lower than the grass, how can I mow the weeds before they go to seed?

I sent a Q yesterday about where to get soil test and CGM, can't wait to buy it and get my soil results. However, I don't know what type of grass I have, so I am unsure of the mowing height, you have mentioned a couple of different grass types and best mower height.

I am considering solarization because the lawn is in poor shape and I'd like to start over. Do I have to till when it is finished, or can I just strip off the dead grass? What type of seed is best to plant for my area? Front is all sun, half the back is shade and the other half sun? When do I seed for my area for optimal results, if I do solarize, or if I just want to seed what I have?

One more...did I read correctly, in my flower gardens I can spray the vinegar mix directly on the weeds and it will not harm my flowers?

Sorry for so many questions, but I am anxious for all the basics and to begin a path to a beautiful organic lawn.

Answer
First, let me apologize for not getting to your question sooner, Susan.  I am badly backed up here and I don't want to cheat anyone out of a complete answer.  So I hope you'll understand I was not ignoring you.  You have asked some big questions here and I want to give you a full answer.

Let's get started.  From the top:

1.  How do you know if your Lawn is going to Seed?

Your Lawn should NEVER grow that long, Susan.  You must mow it regularly, which in Minnesota, thanks to your perfect Cool Grass climate, is ALL SUMMER LONG, twice a week.  Please tell me why you asked that question -- and why you would let your Grass grow that long without cutting it.

At the same time, it is ABSOLUTELY IMPERATIVE that you DO NOT CUT MORE THAN ONE THIRD OF THE BLADE off at any single mowing.  You can damage your Grass badly, even irreparably, by making that mistake.  If it's too long, cut it by 1/3, wait a few days and cut again another third, until it's down where it should be.

FYI:  All Turfgrass comes with a 'collar' where the blades grow from the main stem.  When you mow often, that 'collar' is growing near the surface of the Soil.  But when you DELAY mowing, the 'growing point' rises ABOVE the Soil surface.  Now you have a problem -- because when the Lawnmower runs over that Grass, it slices the collar right off!  Be careful about mowing on time; it really pays off.  You want Grass growth from the collar to stay around the Soil surface.

2.  How do you know if the Weeds are going to Seed?

Sometimes you see flowers.  You can bet your bottom dollar those are going to be Seeds soon.  Get rid of 'em.  A single Crabgrass plant growing in your Lawn will produce 150,000 Seeds before the end of the Summer; many of these will be dormant and viable for years to come.  You can't control Crabgrass in a single growing season.  This is yet another reason to be diligent about mowing your Lawn.

3.  You ask, "If I have to mow higher to strengthen the Grass and reduce Weeds, and the Weeds are lower than the Grass, how can I mow the Weeds before they go to Seed?"

You can't get ALL the Weeds this way.  Some have to be dug up by hand.  And some are headed off at the pass in Spring, with organic pre-emergent Weed controls based on Corn Gluten Meal.

Ever hear of it?

This was discovered by accident at Iowa State a few years ago.  Some researchers were working on problems with grain storage, which is a big problem out there in the Midwest.  They realized that Seeds were not germinating when they were in contact with the Corn Gluten Meal.  At some point, they wondered if there might be a market for a product that stops things from growing.  So they applied for a patent.  Now they license it, selectively, as a pre-emergent, patent-protected Weedkiller.

It comes in large bags of yellow powder labelled 'DYNAWEED', 'SAFE N SIMPLE', PROPAC, CONCERN WEED PREVENTION PLUS, etc.  One new formula puts this in granular form to ease use with Rotary and Drop spreaders.  You put this down right in the early Spring, as Forsythia buds are just beginning to break.  A bag costs anywhere from $25 to $30.  It keeps the Weed Seeds in your Grass that landed there last fall -- Dandelion seeds, Crabgrass seeds, all annuals -- from germinating.  But you have to follow the directions.

What's most wonderful about Corn Gluten Meal is that it doesn't kill fish, it doesn't hurt animals, it doesn't make anybody sick.  It just stops Weeds from sprouting and when it's no longer active, it begins to decompose into a natural, high Nitrogen fertilizer.  No nasty side effects.  No skeletons.  Just good, clean, American Grass.

4.  Mowing height?

Take a sample of your Grass over to your local Cooperative Extension Service and get it i.d.'d.  You need to know this so that you can over-seed when the time comes.  Find out asap.  It will also sharpen your mowing practices -- excuse the pun.

5.   You're considering solarizing...

No can do, I'm afraid.  Minnesota does not get hot enough, long enough, for solarization to make a significant dent in the Weed population.  Then, I could be wrong.  Maybe you get really hot and we just THINK you're cold over there...

But starting over is a great idea.  Don't rototill unless you have really bad Soil that needs to be amended A LOT.  Remember those Weeds we talked about earlier?  Think about this: There are AGAZILLION WEED SEEDS in your Soil WAITING to germinate -- and they'll do that when they are exposed to light and water.  Avoid tilling.

6.  What type of seed is best to plant for my area?

I would go with one of two types.

If you want to really spend a lot of your life working on your Lawn, go with Kentucky Bluegrass for your entire Lawn.  The shaded sections can be grown with Shade-loving Kentucky Bluegrass.  Yes, you read that right -- THE BEST Shade Grass is a state-of-the-art Kentucky Bluegrass variety imported from Germany, 'Supina' (Poa supina).

This is NOT a drought-tolerant variety of Bluegrass.  And it costs a ton of money.  But no Grass grows better in low footcandles.  By blending it with other grasses you can soften the sticker-shock.

Supina is a slow growing Bluegrass.  Sowed Supina takes 2 to 3 weeks to get off the ground -- so to speak.

You can get it on the internet at Seedland.com and at some Garden Centers where they sell premium priced Seed.

If you are going to make your life easy, go with Tall Fescue.  This is a Cool Season Grass that elbows out Weeds all Summer long.  By selecting Tall Fescue, you have picked a Grass that is at the center of some heavy research into the subject of Weed control.

In one test in 2007 at North Carolina State Unversity, Tall Fescue mowed at a height of 4 inches ended the season with ZERO percent contamination of Bermudagrass.

ZERO!

The same Grass mowed at 1 inch suffered from a 95 percent contamination in the same trial.

Mowing is EVERYTHING when it comes to maintaining a Weed-free Tall Fescue Lawn.  The higher mowing captures Sunlight up and down the blade, soaking up rays before they reach feisty, sun-starved Bermudagrass.  This is no small feat.  Bermudagrass is one of the top most terrible things that can happen to a homeowner's Lawn.  With Tall Fescue, scientists have figured out how to stop it.  I can't tell you how pleased I was to peruse the results of that latest trial.  Hot diggity dog!

The trial of which I speak was conducted in one of the USDA Zones where Tall Fescue thrives: Zone 7.  It will do even BETTER in Minneosta.

http://www.cpc.ncep.noaa.gov/

Get your roots off this Autumn (the optimal time to sow a new Grass Lawn) to a terrific start by (hopefully) providing ideal conditions for the Neotyphodium coenophialum Fungus/Fescue friendship that renders this turfgrass so tough.  Believe me, this is a Fungus you WANT in your Lawn if you're growing Tall Fescue.  As the USDA website puts it:

'Agricultural Research Service scientists and their university colleagues have found that the N. coenophialum Fungus seems to perform an important ecological function, helping the plant store more organic Carbon and Nitrogen in the soil.  They have also found that it helps Fescue close its leaf stomates quicker to conserve moisture in a drought, as well as improve growth efficiency.

'In return, the Fescue gives the Fungus a home and a way to get water, energy, and nutrients.  It also gives the Fungus a way to propagate itself by infecting seed so it can live in the new plants.'

Although N. coenophialum lives in Fescue stems, the Fungus still appears to direct root growth toward maximum capture of water and nutrients.  And although farmers don't like this Fungus (it sickens livestock that eats 'contaminated' Fescue), it appears to be the key to super-efficiency of Fescue roots.  The Fungus-infected roots are far superior, capturing nutrients even in the poorest Soil and grabbing H2O under extreme conditions.  Soil with high organic content supports lush growth with less stress.  It can only help your Fescue exercise the kind of muscles it needs to deliver that knockout punch to wayward Bermudagrasses.

7.  The Vinegar mixture you are referring to is just as toxic to Grass and Garden Plants as it is to the Weeds.

Hope this was not overly technical.  I could go on and on and on... Thank you for your question,

THE LONG ISLAND GARDENER