My jugs of perennials have been open for weeks. I open to let water evaporate in the few short hours with no rain. Then I flip them closed, without taping, when the rain is coming back. It does deflect some rain, but they never dry out at all. Most are yellowed from too much water. These annual forget-me-nots are the weirdest looking ones. The cotyledon leaves are the most yellow, that's OK, their job is done. But some of the true leaves are looking yellow-orange.
My few jugs of annuals are still taped closed. I have just a few sprouts of marigold, zinnias, Yvonne's salvia, and euphorbia marginata. Good germination on cardinal climber (ipomoea multifida) and those have been open for weeks. I might actually pot those up, which I never do. But the area where I plan to plant them won't get much sun until the plants are bigger. (If the sun ever comes out, that is).
Karen