One of the gifts from the aril species to arilbreds is the signal
pattern. These are all from some of my seedlings and the effect has
been notable visually in the garden this year. But in the hybrids
between the species, it's often not a well-defined spot. Just as often
it is a concentration of color under or at the bottom of the beards. It
can be distinct or ghostly. Visually it is affected by the color of
both the bloom and the color of the beards. Really dark blooms can all
but obscure it except on close examination. A dark beard or a beard the
same color as the signal area can make a small signal area or a
concentration of lines around a dark beard can give the effect of a
larger center. I don't really concentrate on getting signals, but they
do come along with the territory.
The photo is for fun.
Texas Zone 7 or maybe Zone 8 this year, USA