Before putting your house on the market, attend a few open houses at similar properties in your area. That will give you a firsthand basis for comparing your home with competing properties. It's also a good way to take the pulse of the local market and to spot some of the selling brokers who are active in it.
If the microorganisms have more surface area to feed on, the materials will break down faster. Chopping your garden debris with a machete, or using a chipper, shredder, or lawnmower to shred materials will help them decompose faster.