I have never attempted winter sowing, but I believe the concept is that the plants come up when they are ready to be planted outside. You'll need to protect the plants if there is any danger of frost. You absolutely don't need to plant in groups or hills, they'll grow fine. 200 plants in how big of an area and what variety of pumpkin? For a small variety (less than 6 pounds) if you have that many plants in an area less than 2500 square feet (50' x 50') they are plants far too close. For large varieties (18 - 30 lbs) they should be in an area no less than 6400 square feet (80' x 80'). If you didn't give them that much space it is okay but you can't leave all 200 there and you will have to thin them.

Oh thank you very much,,I have 4 patches going,,,one is round 8',,gourds in that one,,,one is 10 x 12' mixed pumkins in that one,,one in a horseshoe pit,,gourds and pumkins mix,,one is beside our little play wooden house 4' x 4' pumkins in their,,
I spaced them out really good but when they start with the leaves should I put some in another patch??I think by your measurements I have too many for my patches,,did not realalise how much space they take..
Thank you so much for your answers,, do you grow pumkins?
I wanted to sell them for a crop this year they are so expensive here in NY,, thank you Lisa

You have a lot of plants and moving them is really stressful on them. Since you have already moved them once (from the winter sown containers) I would not move them a second time. When they are young you can get away with it. But if they have more than just their seed leaves (the first pair of oval shaped leaves) I would not even attempt to move them. What you need to do is thin them. Look for the weakest looking plants and kill them by cutting them off at soil level. I know it is hard to do but if they are closely spaced those weak plants will compete for nutrients with your other plants and all the plants won't be as productive as they could be. Are you growing them on trellises? You can get away with having them closer if you put them on trellises, plus it will result in a much more attractive fruit if you intend to market them (i.e. you can sell them for more). I wouldn't put the pumpkins on a trellis unless they were small but I would put one by your gourd patch. I do grow pumpkins and gourds and many other squash. I planted most of mine Mother's day weekend and some this past weekend. When I grow the small stuff (mostly gourds) on trellises I make sure each plant has at least 3 feet in all directions from any other plant. Closer than that and you will have weak unproductive plants that are more likely to have pest and disease problems.