Trust, support, unity and humor.
One year early in my surveying career, when it came time to do my taxes, I had a total of 6 W-2s. Five employers said I don't have any work for you next week or whatever. When you're living paycheck to paycheck, not working isn't an option. Don't treat them like a tool and challenge them to aim higher than just a job and a paycheck.
For me, work culture is most important. I’m going to make good money pretty much wherever I go. It’s not worth working for a company with a miserable staff. Been there, done that, hated it. They could drag you right down with them.
I want to ask the technician level people here what they really look for in an employment situation. 'Mo money, of course. But beyond that? What floats your boat? What makes a situation really attractive to you?
I liked having variety. Variety of projects and variety of where I was working-- office or field.
Give them a bonus twice a year. It's not just money. Who can't use a few extra bucks at Christmas or for a summer vacation? It's recognition of a job well done. In Charlotte I met my crews for breakfast every Saturday morning. They got paid to have a free buffet breakfast on the company.
I also made it a point to work with them periodically either cutting line or pounding wood.
You can hire more employees or encourage the ones you have to be more productive.