I just received a beautiful Oregon cedar 8x10 greenhouse as a retirement gift from my husband in May. I have been an avid gardener in Butte, Montana for 25 years. So, I thought a greenhouse would be a nice addition to adding longevity for my tomatoes, peppers and cucumbers. There are 3 raised beds in the greenhouse. At the bottom of each bed I put a layer of small stones. Then black landscape fabric, followed by 12 inches of soil. In one bed I planted 3 tomato plants, the second 2 cucumbers, the third 4 pepper plants. After 3 weeks all the plants were dying. The tomatoes had leaf curl, end blossom rot, and yellowing leaves. The peppers and cucumbers never did "take off". I went to the nursery that sold me the soil for the beds and asked for a hard copy of their soil analysis. The pH in the soil was 9, and all the other soil components were low. I removed all the sad looking plants. Then I removed about 1/3 the soil in all the beds, and I patiently re-added manure, peat moss and store bought topsoil to each bed. After rototilling all the soil mixtures together in the beds, I replanted the same things. And the same thing happened with the plants. My next step was to have a soil analysis done with the county extension office. The pH level was now 6.5, however there was a "trace" of Nitrogen in the soil...potassium levels were very high. Today I removed all the soil from the beds right down to the small stones...hosed down the beds and am starting over. While I will probably wait until spring to add any medium to the beds, any input would be greatly appreciated.

it is just ground plant material but anything helps. If you try to grow in just that you will be disappointed. If you can mix it with horse manure or mushroom compost or a combo of both you will be very happy.

Blueberries won't do well with one dripper. They have a shallow, wide-spreading root system. And they need a thick layer of mulch. Consider a soaker line; Or a rat-tail off the supply line which encircles each shrub at the drip line. Even then, you will have to move the rat-tail each year to deal with the expanding rootzone. Yes, Ts will work. Get one of the freebie booklets at your local box store. And no, you don't have loamy soil. You have something more like potting mix. So, yes, sprayers make sense. Just as with drippers, you should not exceed the supply -- the combined water pressure and the diameter of the supplyline. (That freebie booklet will help you figure it out.)

I can't resist pointing out that all "soil" is organic but if you are referring to a certified "organic" soil-less potting mix then many brands are available. You will still have to supplement minerals and nutrients of course. However most find the $$ cost of going that route prohibitive when it comes a raised bed of any size. There are any number of previous discussions here about "best or favorite" raised bed fill and in most cases a simple blend of peat, top soil, and compost is the common go-to method. The next best alternative is to purchased a bulk quantity of quality landscaping mix. Lastly, existing soil can always be revitalized with staged doses of a high quality compost. Coco coir has its advocates but it also has its detractors, its problems, so I'd encouraged you to not go overboard with its use lest you make your problems worse. Dave https://www.gardenweb.com/gardenweb/query/best-raised-bed-mix