Is the well 1.5" on the sprinkler side of the pump outlet? Any what idea the well pump is in sized and depth? Any model number? Is it above ground jet or submersible? What size sprinkler pump? With 2" fittings it'll be 1.5HP or 2HP. A 1.5" pipe from the well is maybe only 3/4HP or 1HP. You cannot increase pressure if the pump cannot handle the demand. Your well pump is on a pressure tank with a pressure switch setting at 30/50. Some of the pump energy is working against the pressure tank so you're losing some there. Increasing the pressure switch (or change it out) to 40/60 may over work the pump. It is why the pump mode number to look up what the well pump is.
To use a well for domestic and irrigation, you'll need to increase the well size and the pump or just a larger pump if the pipe can fit a larger discharge pipe. For best performance and to save the pump motor, a CSV valve would be needed. Now you're talking big bucks, a new well and a larger pump. CSV is not that expensive to retro it to your existing domestic well.
Original scan Truth or Myth Busting the common Myths about Constant Pressure Water Pump Control Valves Over the past 30 years you have probably seen multiple articles on constant pressure water pump control valves (CPV). Every article talks about the "magic" of these simple mechanical valves...
cyclestopvalves.com
Another more simpler solution is just have another well added and use it just for irrigation only.
Assuming you connected it to sprinkler manifold, you may need a check valve so the well water doesn't go back to the sprinkler pump, however it is almost a given that there is a check valve at the pond intake but you might just want to check it out.
I've lived in Florida now for 33 years and I find most over water the lawns during all seasons. To save the pond during the dry season, back way off on the irrigation times. Winter months like right now 15 minutes per zone is usually good enough two times a week. Depending on sprinkler types the fifteen minute is for regular popup or rotors. My home here in the east end of Orange county, I manually turn on the irrigation system when things start to look stressed. I might let it run for a week or two before turning off the timer. Summer time with our usual storms, I'll hardly water. All lawns do seem to have a spot or two that drys out from too much sun, then you make timer adjustments or hand water it occasionally.