actually while I think about it Bidens also goes by the common name of tick seed because the ripe seeds stick to clothing by a tint hook at their tip. The seeds of my plant are like minute sunflower seeds maybe 3mm long x 2mm. They are grey with black flecks

When did you plant these daisy things? How much Epsom salts did you give them? Is the Daisy Gardenia one of those little radicans varieties? Yellow leaves are a way of life with most gardenias, usually a temporary stage of discarding old leaves when new are coming on or there's stress. Short bloom life may be a characteristic of this one. Have you given them at least to the second year to prove themselves? The old tried and true are starting to bloom here. Not every bush has an open bloom, yet. I haven't tried any other because they are so dependable. Nell

That's the problem with common names. The plant usually referred to as Montauk Daisy is Nipponanthemum nipponicum. Ajania pacifica is another plant, same family, Asteraceae. Could be a sort of "nickname" for the Ajania.

Correct, both Senecio plattensis and S.aureus are now Packera plattensis and P.aurea I beieve the plant is P.aurea -- look at the basal leaves clearly seen on "Yellow weed pt2" link above. Compare them to plattensis/aurea basal leaves (more images could be found under the old name -- Senecio aureus).