Please forgive my silly question, but what is the reason for planting 3 to 6 seeds per hole, as recommended on the seed packet directions? Is it just because some of them might not grow and it makes it easier to space them correctly when you go to thin them out? Because I have found that it's rare for something not to sprout, and it makes me nervous to transplant little sproutlets. I don't want to stress or possibly kill them. (Obviously I'm new at this!) I was just curious to see if there's another reason. Thanks!
You stated the right reason--multiple seeds in one place is insurance that you'll get seedlings. I have the sneaking suspicion that it also helps the seed companies sell more seeds! I usually confine myself to three per hole--six seems like overkill. If I need to transplant to fill in gaps in the row, I wait until the seedling gets its second set of true leaves (unless of course it's a root crop, when I just yank out the extras and feed the hens).
I don't put most seeds directly in the ground. I have a way of forgetting and accidentally "weeding " them out before they get through the soil. So I start most of my "three to a hole" seeds in flats and then I plant them into the ground as soon as they have ONE true leaf. Cukes, watermelon, squash, cantaloupe, etc. I don't let any of them get a tendril on the plant before they go into the ground. letting them get that size seems to stunt them rather than give them a good start. As soon as they are ready to go into the ground I turn the cell pack over and gently squish/squeeze working the plants out of the cell best I can to keep the soil together, but I don't worry if it falls apart, just try to keep the roots from breaking off. This is more than you were asking, but, no there is not really a great reason to plant so many to a hole and go back and thin them out. Some seeds are expensive and I feel wasteful tossing perfectly good plants, just because some one said to plant 3 to a hole and I am supposed to go back and thin it down to "1 every 6 inches" or whatever the directions are.
I just plant three seeds per hole. But I spread them about an inch or two apart and if all come up,, transplant the others farther down the row.