Okay, so I started a garden for the first time. I put in cucumbers, tomatoes, onions so far and have green beans sprouting. My question is this: I have already had to replace 6 of my cucumber plants and now it looks like I may have to replace more. I prepared the bed well, tilled it, added fertilizer, have been watering frequently, all the other plants are doing wonderful. But not my cucumbers, they have been slowly shriveling up and dying on me. Any suggestions?