Sounds like you might need to put a little more effort into your hiring process in order to increase your chances of hiring employees who will be a good fit for your company.
You are the one who makes the decision to hire. Don't make the decision to hire until you have acquired a reasonable assurance that the candidate sitting in front of you is the right person for the position you have available.
Get a few books on hiring employees/conducting interviews/managing your employees.
Here is a list of books I recommend:
How To Become A Skillful Interviewer by Randi Toler Sachs
How To Hire The Right Person by Denis L. Cauvier
Hire Your First Employee by Rhonda Abrams
The Manager's Book of Questions - "751 Great Interview Questions For Hiring The Best Person" by John Kador
The One Minute Manager (this is a series of books) by Kenneth Blanchard and Spencer Johnson
Everyone's A Coach by Don Shula and Ken Blanchard
Managing For Results by Peter Drucker
Management Basics by John & Shirley Payne
13 Fatal Errors Managers Make And How To Avoid Them by W. Steven Brown
Leadership Secretes From The Executive Office by George Hathaway
The E-Myth by Michael E. Gerber
A. W. Landscapers, Inc.
Hustler X-One 60"
Wright Stander RH 36"
eXmark 21" ECXKA21 Mower
Stihl FC110 Edger
Stihl FS90 Trimmer
Stihl FS55R Trimmer
Stihl HS56C Hedge Trimmer
Stihl MS391 25" Bar Chainsaw
RedMax EBZ7100 Blower
Earthquake 16" Rear Tine Tiller
Honda 9" Mini Tiller FG110
2014 GMC Sierra Denali HD
7' x 16' Enclosed V-Nose Trailer
6' x 12' Dump Trailer
Equipment & Trailer thread: http://www.lawnsite.com/showthread.php?t=415830