I understand about the weeds. It's a never ending battle for me and keeping up with them IS my job. I turn around twice and they are back again and a foot tall.
Dig a hole down about a foot or so deep and see how far down the soil moisture goes. If you have moist dirt down to the subsoil, water is not the problem. But it is easy to get fooled by how much rain and water you are putting on. It almost never rains here in summer. I depend 100% on irrigation with overhead impulse sprinklers. If I don't get them set to overlap correctly it is easy to put plenty of water in one area and not enough in another, or near the outer portion of the circle. It all can look the same on the surface when I shut them off. Nice and moist. But it may have not gotten down very deep near the edges or where they don't over lap. And then if a little rain happens along it re-moistens the surface and everything appears good and to dry down at the same rate. But little water may have ever made it down into the main root zone.
Even after all these years of growing I still get fooled by this sometimes. I did again this year. I have a small patch where I grow far enough away from my main field that I don't have to worry about cross pollination and bag all the plants. I have about 120 Virginia Bright Leaf growing there this year. It's small enough the sprinkler is set on half circle. It's a big impulse sprinkler mounted about 7' off the ground on a pole. A couple weeks ago I noticed in one corner of the patch how that plants were all smaller than the rest and on very hot days they wilted when the other didn't. I never had problems with this area before. It had me stumped. There are a line of trees about 15' back on one edge to the north behind the sprinkler pole. Then one day I noticed that a branch had grown out far enough over the years and was hanging down and was deflecting the water at the high end of the arch of the stream from the sprinkler to that corner. And only about half the water it needed was getting to that area. I had to get a ladder and haul out there to prune it back. The plants are doing better now but they will never catch up. I am watering this spot right now and it's about time to drive out there and shut it off. I'll try to get a decent pict of what it looks like and you will see what I mean.
As fertilizer goes, it needs the right amount, no matter what the cost. And the cost has gone way up! I'm paying 3 times what I did 10 years ago and it was up 50% this year alone over last year. So I have two choices. Pay what ever it takes to get the right amount on or watch my yields suffer badly.
