I have a slightly different take on astrology. Most of the commonplace uses and interpretations of it are silly. Especially the random "signs" based on constellations etc.
However, growing up on a farm and learning about planting of crops, moon phases and time of year...I think there is a definite correlation between certain shared personality traits and date of birth that's influenced by the sun, moon, gravity, etc. These have been fit loosely into the so called zodiac but to me it seems larger than that.
For example: if you're planting sweet corn in the part of Ohio/North American I grew up in, there's a specific window of time to plant in order to get the tastiest corn. However, you don't want it to all ripen at the same time. So we used to plant some before a full moon and others after (as advised in the Farmers Almanac no less.) Even though the seeds could be planted a week apart, the seeds planted after the full moon would likely ripen nearly a month later. I used this same guidance for cutting my hair. If I want it to grow slower, I get a cut after a full moon. If I want it to grow more quickly, I get it cut a few days after the new moon. I've gotten several of my friends to do this and all are amazed that it works.
Recently, I was in a MAP/Excel training session, which works from a variation of Briggs-Meyer developed specifically for managerial skill assessment. At one point in day 2, as we were reviewing our assessments and being group into our "management personality style" types...I became curious as to when the other people at my group (thinkers) had been born. So I asked. All 5 were born in May or early June or late Nov/Dec...meaning we were all late Taurus/Gemini or Saggitarians. Another table was all Aries/Taurus and Scorpios. It gave the room a good chuckle, but made me think a little more about how our personalities might be impacted by conception/birth time of year and the gravitational/solar forces.
Yes, it all seems cliche when read in horoscopes and what not. But when I meet other "Geminis" it seems equally implausible and undeniable that we share similar personality traits and such despite not being siblings/twins/friends/etc.
I'll stop here because I'm probably coming across as a total kook. I still think astrology (as in reading the stars, etc) is silliness...but I also think "birth"dates impact us, same as other environmental and genetic factors that we don't fully understand aid in shaping our sum total personalities.