House cost basis for (re-) seeding field

Seven years ago, we built a home on 5 acres of old farmland, and have been trying to get the weed under control ever since. We've paid somebody to fertilize and plant field grass on 3 separate occasions, but -- due to the fickleness of mother nature -- have so far been unable to get the field established.

 

I know that landscaping and material improvements that increase the value of a property generally generally contribute to the cost basis for that property. But what are the limits of that? Would all of my expenses thus far (ground prep + seeing/fertilizing in 3 separate years) qualify? What if the the field never actually gets established, or only does so partially?