In the past I've been somewhat blasé about plant spacings, but sitting down with ye olde calculator has opened my eyes. The permanent high tunnel that we use is 22' x 60'. I've divided the plot into 5 rows with 4 aisles. The narrowest aisles that I seem to be able get away with are 18". Subtracting 72 (18x4) from 262 (22x12) divided by 5=38.4" width/row.
Rounding off to 36", or 3', x 56' (leaving 2' at either end of the row for walking) = 168 square feet per bed.
Here's where the math comes in.
The most common spacing I use is 6", which comes out to 4 plants/square foot. Filling a bed would use 672 plants. However, if the plants are spaced more tightly, at 4", the number of plants needed jumps to 1512. That's a lot more plants!
Is it possible to space the high value plants more closely and still get a good set of blooms? Can I provide enough nutrients and be able to keep enough air circulation for healthy plants? Gonna need to do some experimentation.