I have problems here with the tree rats and peanuts also. Except that it's one of the neighbors that feeds them peanuts. They just love to bury them in my yard. What I've come up with is covering newly planted beds with rolled fencing material. Looks something like this: http://www.vinbiz.com/fencing/stablemesh/4x100-stablemesh-fencing

Here in the north, peanuts aren't the easiest thing to grow, but it can be done. Most important thing is to get them going ASAP -- they need a long growing season. They also enjoy heat, so you might want to plant in a sheltered microclimate, etc. You can use black plastic around them, but be sure to leave about an 8" circle cut out, so the blossom stems can bury themselves in the soil, where the peanuts form. Also, they like sandy soil, even moisture, lots of fertilizer, and you might need to use some fungicides, as they are prone to various rots, etc., in cooler climates.

I have found that the peanuts survive fine in the soil over the winter, and that there are quite a few sprouts in the spring. You do want to thin the plants once they get going, because there may be quite a few more than you want. However, do wait until well after your last frost, because some of the peanuts may come up before damaging frosts are over, and will be killed. Other seeds will sprout later, still giving you a crop. For what it is worth, the shells rot over the winter, but the seeds seem to be just fine. Renais

Here is some general information for you from the International Fertilizer Institute: Preferably based on soil tests. If pH is low and liming is recommended, limestone should be broadcast and turned into the soil in early spring. Most USA research indicates no response to N when the soil is limed to an adequate pH and inoculated with the correct Rhizobium sp. On the other hand, many responses to N have been obtained in other countries. Few responses to P and K have been recorded in USA since the rotational crops usually have higher requirements. Responses have been reported, however, under very low fertility conditions in Africa and in particular in soils with high P fixation. Basal applications of P and K (and of N too in several countries) are usually broadcast and incorporated into the soil before planting. Some topdressings of small amounts of N are applied at the vegetative stage in China. Gypsum application (to supply Ca and S), by broadcasting or banding at flowering, is common. B and Mo are commonly applied in foliar sprays at the vegetative stage. Present fertilizer practices USA Limestone broadcast and turned into the soil before planting if pH Gypsum applied at bloom to small-seeded types, when Mehlich 1 extractable Ca Boron at 0.6 kg/ha B (unless soil level > 0.5 mg/kg B) usually in foliar sprays, split between the first two fungicide applications.