Bring the 1.5 litres of water to a full rolling boil. Remove from the heat immediately and allow the water to stand for 30 seconds — a brief pause to drop from 100°C toward approximately 90–95°C. Add the lemon verbena leaves — either the fresh cup measurement loosely packed or the dried ⅓ cup measurement. Cover the vessel to trap the volatile aromatic compounds that would otherwise escape as steam. Steep for 10–15 minutes, tasting at the 10-minute mark by lifting the cover briefly and smelling rather than tasting directly — the aroma at 10 minutes should be vivid, specifically lemony, clean, and floral. If the aroma feels mild or insufficiently present, steep to 15 minutes. Do not steep beyond 15 minutes: lemon verbena's pleasant aromatic character comes primarily from citral and other volatile lemon-scented compounds that extract rapidly and pleasantly in the first 10–15 minutes. Extended steeping progressively extracts the less pleasant grassy, slightly bitter back-notes from the leaf's fibrous matrix and from other aromatic compounds that are slower to extract and less pleasant when present in concentration. The difference between a 12-minute verbena infusion and a 2-hour one is the difference between a specifically fragrant, clean, lemon-forward tea and a slightly bitter herbal tea that happens to smell of lemon. Strain completely through a fine-mesh sieve, pressing gently on the leaves to extract the infused liquid. Discard the strained leaves.

While the strained infusion is still warm — immediately after straining — stir in 3 tbsp of honey until completely dissolved. The warm infusion's temperature is sufficient for full dissolution without any additional heating. Starting with 3 tbsp (approximately 60g) is the calibrated starting point for a delicately sweet result that lets the verbena's aromatic character dominate; taste after chilling and add more honey at that stage if a sweeter result is preferred.

Allow the sweetened verbena infusion to cool completely to room temperature — approximately 20–30 minutes at room temperature or 10 minutes set in a bowl of cold water. Once cool, stir in 30ml of fresh lemon juice. The lemon juice's function in this recipe is specifically as a flavour-sharper rather than as a primary flavour component. A small quantity of lemon juice in verbena tea tightens the aromatic perception of the verbena's own citral character — making the lemon-herbal flavour taste specifically more vivid and more clean without the lemon becoming a detectably separate flavour in the foreground. At 30ml in 1.5 litres the lemon juice is present as this background sharpener; at 45ml it is slightly more present but still supporting the verbena rather than competing with it. Taste and add up to 45ml total if additional brightness is wanted.

For the most aromatic version — specifically recommended for fresh lemon verbena in season where the leaves are at their most volatile and fragrant — add a small handful of additional fresh lemon verbena leaves to the cooled tea before refrigerating. Cover and refrigerate for 1–2 hours, then strain out these cold-infusion leaves. The cold infusion extracts an additional layer of the leaves' most volatile, most specifically fragrant aromatic compounds at the low temperature where they transfer slowly and specifically into the cooled liquid without the grassy extraction that warm steeping would produce. The cold-infused version has a notably more vivid, more layered aromatic character than the warm-steep-only version. Remove all leaves and any lemon slice additions before overnight refrigeration — extended contact of tough stems and citrus pith in the refrigerator develops a slightly bitter note over time.

Transfer the finished, strained tea to a sealed glass pitcher. Refrigerate for a minimum of 4 hours — ideally overnight. The extended chilling period is specifically more important for this preparation than for any other in this collection: lemon verbena's aromatic compounds continue integrating into the liquid during the cold rest, and the flavour difference between a 4-hour-chilled tea and a 12-hour-chilled tea is specifically noticeable — the overnight version has a more fully integrated, more harmonious, more specifically aromatic character than the minimum-chilled version. Fill glasses with ice. Pour the chilled lemon verbena tea over the ice. Garnish with a lemon slice and a fresh verbena sprig if available. Serve immediately while the aroma is clean, citrusy, and delicate.