Question
I have a new home on 1.5 acres in NE Nevada where the soil is hard pack compacted clay.  I read about alfalfa as a green manure and want to try it as a cover crop but am concerned about the alfalfa seeds germinating in with my lawn seed later. So I would like an answer to the following questions:
1. Will I get Alfalfa growing later in my DIY seed planted lawn?
2. Is Alfalfa a good choice to grow in my short seasoned area.
3. Is there a specific Alfalfa that I need to purchase for best results.  And last,
4. Do I need to apply any amendment to the alfalfa seed?


Answer
Good old fashioned Cover Crops are the perfect answer to cure Clay Soil.  Thanks to that Clay, your Soil is already HIGH in Calcium -- very good for repelling Dandelions and other weeds when you eventually grow Grass.

'Green Manure' -- the term for plants in the Legumes family -- fortifies your Soil with mega-doses of instantly usable Nitrogen.

Alfalfa.  Wheat.  Vetch.  Peas.  Rye.  Clover.  These plants CREATE Nitrogen out of thin air.  And if there's anything you need to grow healthy Grass, it's Nitrogen.

As you suggest, these are usually grown during the Summer.  They can be tilled in before they reach maturity.  Even better, the roots of some Green Manures draw nutrients UP toward the soil surface, where your Grass can use them.  At that point, you can count on having the richest, most fertile soil in town.

As one professional put it:  'The addition of organic material is perhaps the most important ingredient in healthy root development.'  Soil Microbes live happily ever after when you enrich your Soil with Green Manure and other organic matter.  Those Microbes are the MOST EFFICIENT FERTILIZERS IN THE WORLD, turning organic matter into Lawn Food that roots can absorb easily.

Your Clay needs it.  And so does your future Lawn.

Let your Alfalfa, or whatever crop you use, grow 3 or 4 inches tall.  Then mow it down and pitchfork the leaves, and stems, and roots into the soil.  And don't worry about it growing in your Lawn.  If you turn it under before it blooms or sets seed, it will be here today and gone tomorrow.  Just make sure it doesn't get a chance to flower.  No flowers, no seeds.

You need NO additional ingredients for this exercise; the Alfalfa does all the work.  Just keep it watered when it gets dry, and take the Mowing VERY seriously.  Any Alfalfa will do.

And yes, Alfalfa is a GREAT choice.

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