August care

Lemon balm in August: monthly care

Month-by-month careMelissa officinalis

In August your lemon balm needs attention: prune, harvest and watch the bloom.

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  • Prune
  • Harvest
  • Blooms
Lemon balm (Melissa officinalis)
Foto: Onbekend / Wikimedia Commons / CC BY-SA 3.0

What to do this August

Prune

Lemon balm benefits from regular pruning to keep it productive, compact, and prevent it from becoming straggly or self-seeding prolifically around the garden. The main pruning periods are June and August, which coincide with the plant's vigorous growth and flowering phases during summer. In June, once the plant has put on substantial leafy growth, cut it back by about half to two-thirds of its height using clean, sharp secateurs or garden shears. This encourages a fresh flush of tender, flavourful leaves and delays flowering if you want to prioritise foliage production over blooms. If you allow lemon balm to flower—which is beneficial for pollinators—deadhead the spent flower spikes promptly to prevent prolific self-seeding. The small white flowers are attractive but the plant can become invasive if allowed to set seed freely. Prune again in August after the main flowering period. Cut the whole plant back hard to about 10–15 cm above ground level. This rejuvenates the plant, promotes bushy regrowth, and provides a final harvest of fresh leaves before autumn. The new growth will be more compact and less prone to mildew, which can affect older, congested foliage in damp conditions. Use sharp tools to make clean cuts and avoid tearing the stems. You don't need specialist equipment—kitchen scissors or secateurs work perfectly well. If your lemon balm looks tired or diseased at any point during the growing season, don't hesitate to cut it back hard; it recovers quickly and will reward you with healthy new growth within a few weeks.

Harvest

Lemon balm is a low-maintenance herb once established, requiring only moderate watering and minimal feeding. Water regularly during dry spells in spring and summer, aiming to keep the soil evenly moist but never waterlogged. In hot weather, plants in full sun may need watering once or twice a week, while those in partial shade or heavier soils will need less. Reduce watering significantly in autumn and winter when growth slows. Mulching around the base in spring with garden compost helps retain moisture and adds a gentle nutrient boost. Feed lemon balm lightly in April with a general-purpose organic fertiliser or a sprinkling of blood, fish and bone worked into the soil surface. Avoid high-nitrogen feeds later in the season, as these promote soft, sappy growth that is more susceptible to disease and less hardy going into winter. Lemon balm is not a heavy feeder and too much fertiliser can reduce the intensity of its lemon fragrance. This herb is fully hardy in zones 4–9 and requires no special winter protection in temperate Europe. The top growth dies back in late autumn; cut it down to ground level in November and the plant will reshoot vigorously from the base in spring. A light mulch of compost over the crown provides extra insulation in colder areas but is not essential. Lemon balm is generally pest-free, though aphids occasionally cluster on young shoots in spring—wash them off with a jet of water. Powdery mildew can appear on older leaves in humid conditions, particularly if plants are overcrowded or not pruned regularly. Good air circulation and cutting back congested growth in June and August minimise this problem.

Blooms

Lemon balm is a low-maintenance herb once established, requiring only moderate watering and minimal feeding. Water regularly during dry spells in spring and summer, aiming to keep the soil evenly moist but never waterlogged. In hot weather, plants in full sun may need watering once or twice a week, while those in partial shade or heavier soils will need less. Reduce watering significantly in autumn and winter when growth slows. Mulching around the base in spring with garden compost helps retain moisture and adds a gentle nutrient boost. Feed lemon balm lightly in April with a general-purpose organic fertiliser or a sprinkling of blood, fish and bone worked into the soil surface. Avoid high-nitrogen feeds later in the season, as these promote soft, sappy growth that is more susceptible to disease and less hardy going into winter. Lemon balm is not a heavy feeder and too much fertiliser can reduce the intensity of its lemon fragrance. This herb is fully hardy in zones 4–9 and requires no special winter protection in temperate Europe. The top growth dies back in late autumn; cut it down to ground level in November and the plant will reshoot vigorously from the base in spring. A light mulch of compost over the crown provides extra insulation in colder areas but is not essential. Lemon balm is generally pest-free, though aphids occasionally cluster on young shoots in spring—wash them off with a jet of water. Powdery mildew can appear on older leaves in humid conditions, particularly if plants are overcrowded or not pruned regularly. Good air circulation and cutting back congested growth in June and August minimise this problem.

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