I haven't really been on s2ki for some months, however there is some good and not so good advice in this thread. Probably the best advice in this thread is to talk to your local Extension ag/horticultural agent.

The second thing that I would stress is a soil test before you plant anything. Most County Extension services have some sort of state-wide soil testing station for both commercial businesses and home owners. For example, NC State University in NC offers a free soil testing service (tax subsidized) for its residents. This type of test will let you know what your soil is lacking and is a great start. The testers will give you a full analysis of your soil and will give you crop specific recommendations. Only thing is NH may be a state that charges for soil testing. Are your soils more mineral or organic (organic meaning do they have lots of humus organic material)? Mineral soils (such as clay soils) typically are more acidic since organic matter acts as a pH buffer. In NC, we have mineral soils and therefore we can grow acid loving plants easily.

Be careful of generic statements like 'give doses of epsom salt' or 'clay is good because it holds water'. While there may be truth in these statements, it is only relevant to what types of crops you are growing. Blueberries do need acidic soils, but your soils may be acidic enough and that would be another thing that the soil test would provide--therefore saving you from making Now I'm not a big expert on fruit/vegetable crops (I work with greenhouse and woody ornamental crops), however I am a firm believer in bed preparation which is why I'm really pushing the soil test.