I HAVEN'T GROWN THE 'PEARL', BUT I DO GROW a RED ONE I LIKE. IT IS A RED CURRENT RED...NO LONGER REMEMBER THE NAME OF IT BUT IT MIXES WELL WITH EVERYTHING. I BOUGHT RED VELVET FROM WAYSIDE THIS YEAR AND HOPE THAT IT IS THE SAME ONE OR SIMILAR.
I am trying the 'Summer Berries" collection from seed this year. I liked the Colorado mix . I find any color easy to use when I am making multiple bouquets. I like terra cotta with hot cocoa roses!

Angel's Breath and Ballerina, both white. I think they're prettier than The Pearl. The Angel's Breath is about 2' high and Ballerina is about 12". They bloomed all summer for me and looked clean and fresh and looked so pretty with the roses. They make a nice substitute for babys breath and can take our heat.

Here's where I got mine:

Here is a link that might be useful: achillea ptarmica

The pearl is floppy here, although I do grow it.

My favorites are a pink that turns paler - so it lasts a long time, terra cotta (nice with gaillardia), and some purple that a GW trader sent me. It is a slightly later blooming plant. I just wish I could find a yarrow that bloomed almost all summer here!

GGG

The Achilleas I did best with in Wisconsin were the hybrids out of Europe. The best of those, for fresh and dry cuts, were 'Fireland', 'Appleblossom', 'Paprika', 'TerraCotta', and 'Sandstone'. 'Heidi' was the best-colored but it was only good fresh; it dried brown.

I grew 'The Pearl' but it was a dilemma. It had the longest stems in the shade but it was a floppy fresh cut. In the sunnier, drier areas, it had strong straight stems but the stems were short.

Joe