Adding fertilizer to soil should be based on a soil test that gives you an idea of the current fertility and what is needed. Organics are my first choice when available. If you could add a 2 inch layer of rabbit manure to each raised bed, you would not have any fertility problems.

For a comparison, I made several beds for peppers this year by adding a bale of peat moss (about 50 pounds) and a bale of alfalfa hay (about 50 pounds) to an area roughly 12 feet wide by 30 feet long. Then I added about 5 pounds of 13-13-13 fertilizer and about 20 pounds of lime. This was just about right for my peppers which are now yielding a huge harvest. The same treatment would have been woefully inadequate for corn which needs a lot more nitrogen.

DarJones

"If you could add a 2 inch layer of rabbit manure to each raised bed, you would not have any fertility problems."

My daughter has pet rabbits kept inside. She uses wood pellets in their litter box. Having heard that rabbit manure is excellent fertilizer, I advised her to apply the discarded litter to her garden. Big mistake! Growth of her pole beans was insignificant. In hind sight I realize that decay of the wood pellets depleted nitrogen. Manure without the wood pellets would be fine, if you have it.

Jim

Get a good base of where you're at by getting a soil test. Some soil tests don't do N because it's so volatile in measurement and mobile in the soil.

After you adjust for pH (important, if adjustment is even needed) you can look at your P/K+micronutrient levels to see what may (if at all) help you need there.

As far as N goes...if you go organic you need to do it properly and work enough organic material in. You have to do it right or you may not get enough N. A lot of organic solutions/mixes/powders provide very low N and bulk is key (such as incorporating 2"+ of manure like the poster above). Organics tend to be very awesome at providing a range of micronutrients and some (such as manure) do wonderful things for the soil profile.

When going chemical for N try not to use too much. It sounds like you're going to try to have a garden that will be in production most of the year. I find that with a proper soil pH range and a good supply of P/K + micronutrients, I only need to apply a "normal" dose of N fertilizer a little after planting time after the seedlings have set decent roots, and occasionally late in the season. I use a 24-8-16 that has micronutrients in the mix, myself.

Thanks everyone for your advice. I agree, getting a soil test is a very good idea and something we definitely want to do this year. With raised beds is it a good idea to get a test for each bed or can soil be mixed together into one sample?

If the raised beds are very similar in what they are built from and crops have been regularly rotated, you might get by with one properly collected soil test.
I find that some of my beds have had more organic materials added than others.

Along with a soil test, observe the plants. I often get a soil test that shows my nutrients are very high due to the organic matter I add to the soil, yet I will usually get signs of nitrogen deficiency in my corn. When signs of deficiency start, I will side dress everything with some 30-10 and that does the trick.

While different plants may prefer nitrogen/phosphate in a slightly different ratio for best growth, I wouldn't buy 10 different mixes to get everyone their favority ratio. Just get one fertilizer, usually higher in nitrogen than the other nutrients as that is usually the most limiting factor. The other nutrients will then either be sufficient or in some excess, but won't hurt the growth. Overloading the phosphate or potash can contribute to shortages of other nutrients that are sufficient in the soil but get "locked up" by having very high levels of other nutrients. I don't mean to be contradictory here, mild excess=no problem, extremely high excess=potential problems. I like having a high component of nitrogen because it is the most likely to be lost from the soil and used by the plants in the highest quantity. The others don't move as easily in the soil and are used in lesser amounts, so a completely balanced fertilizer, like 10-10-10 can leave you with way too much P and K if you supply enough to meet the nitrogen needs, or can leave you short of nitrogen if you only supply enough to meet the P and K needs.

Start with the soil test, fertilize as recommended, then watch the plants and use additional fertilizer if they show signs of shortage.

Sometimes the levels of nutrients aren't the reason things don't grow like crazy. Weather, soil conditions, moisture levels, heat levels, and competition from weeds or other plants can all affect performance regardless of having optimum fertility.