We did not find the heart, but from the cache description it is easy to guess the values (or they are already given). The resulting location is somewhere inaccessible in the valley, but the only possible way towards the point leads to the information about the name of the plant. So, all in all, we solved the puzzle and were able to locate the final location, where we easily retrieved the cache. Nice little hike and nice location!
TFTC - Fogg & Consortin