The organics will show up one way or another. Often the aromatic group will absorb the UV giving a dark spot but if the organics fluoresce themselves then it will likely be a different color from the green fluorescence of the TLC plate so they will still show up. Another quick way to visualize the organics on a TLC plate is to expose the plate to iodine vapour, the organic will absorb the iodine vapour causing a visible dark spot.