Begin by scooping the honeydew melon into balls using a melon baller, or cutting it into cubes if you don't have one. Rinse the blackberries gently under cold water and allow them to dry completely. Wash the watercress and pat it dry. Slice the shallot thinly.

In a large mixing bowl, add the honeydew melon balls, blackberries, watercress, and sliced shallots. Gently toss these ingredients together.

In a small bowl, whisk together the olive oil, lemon juice, honey, and sea salt until fully combined.

Drizzle the dressing over the salad and gently toss to coat. Serve immediately.

If not serving right away, store it in an airtight container in the refrigerator for up to 4 days.