Wash all vegetables thoroughly. If using garden cucumbers, peel them first as the skin can be bitter. For English cucumbers, leaving the skin on is fine.
Slice cucumbers into thin rounds (about 1/4 inch thick) and place in a large bowl.
Cut tomatoes into wedges or bite-sized pieces and add to the bowl.
Thinly slice the red onion and add to the mixture.
In a small bowl, whisk together lemon juice, olive oil, minced garlic, and honey until well combined.
Pour the dressing over the vegetables and toss gently to coat.
Season with salt and pepper to taste.
Sprinkle with fresh parsley and feta cheese if using.
Let the salad rest for 5-10 minutes before serving to allow flavors to meld.