Wild basil

Wild basil: how do you recognise it?

Habit

Loose, upright plant 30–50 cm tall and about 30 cm across; forms small groups with short runners.

Leaves

Oval, slightly toothed, opposite and softly hairy; faintly aromatic when rubbed.

Stem

Square and hairy, as in many members of the mint family.

Flower

Small two-lipped flowers in dense, round whorls at several levels along the stem, from July to September.

Colour

Pink to purplish pink, rarely white.

Bracts

Narrow and bristly around each whorl; they give the flowers a woolly look.

Flowering: July–September · Sowing: March–April · Plants: March–April and September–October · Pruning: March

Why grow it?

• A native plant that suits a natural garden and local insects.
• Attracts wild bees, bumblebees and butterflies from July to September.
• Tolerates drought and poor, chalky soil.
• Also grows in light shade, for example at the edge of a hedge or woodland strip.
• The spent whorls stay standing through winter and give structure.

Wild basil: where does it grow best?

• Sun to partial shade; it is at home on a woodland edge or beside a hedge.
• Free-draining sandy, loamy or clay soil, neutral to chalky; acid soil is less suitable.
• Dry to moist; poor soil gives a more compact plant.
• No fertiliser or rich compost: on fertile soil it is swamped by stronger plants.
• Plant 25–30 cm apart, preferably in small groups.

Light

Sun and partial shade

Soil type

Sand, loam or clay

Acidity

Neutral or chalky

Moisture

Dry or normal

Size

0.5 m tall, 0.3 m wide

Hardiness

Hardy (to -35 °C)

Goes well with

• Wild marjoram: Another native member of the mint family for the same dry, chalky soil; together a feast for bees.
• Knapweed: Purple flower heads in summer, also loved by butterflies.
• Agrimony: Yellow spikes on the woodland edge.
• Yarrow: Flat white flower heads beside the pink whorls.
• Oxeye daisy: White flowers in early summer, before the wild basil starts.

Wild basil: when and how to plant it?

Plant in March–April and September–October.

1. Plant in March–April or September–October. Sowing in situ is possible in March–April.
2. Remove perennial weeds and vigorous grasses, which would otherwise smother the young plants.
3. Dig a hole slightly larger than the pot and set the plant at the same depth.
4. Leave 25–30 cm between plants.
5. Water after planting and in dry spells for the first few weeks.
6. Do not mulch with a thick layer of compost: a poor, open soil is better.

Care

Watering

Only after planting or sowing and in long droughts in the first year; after that it looks after itself.

Feeding

Not needed, even undesirable.

Deadheading

Leave the spent flowers: they give seed and a fine winter outline.

Self-seeding

It self-seeds moderately; keep seedlings where they fit in.

Mowing

In a flowering meadow, mow only after the seed has set, in September, or in early spring.

Tip: Sow or plant it in a strip along a hedge or woodland edge on poor soil: it will stay there for years and become a regular stop for wild bees.

Wild basil: when to prune it?

Pruning months: March.

When: Late February–March, before new growth begins.

How:

• Cut the old, dead stems back to just above the ground.
• Pile the cuttings at the back of the garden: insects may still be overwintering in them.
• No pruning is needed in summer.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed

In March–April, in situ or in a tray; barely cover the seed and keep it moist.

Division

In March or October, split a clump and replant straight away.

Cuttings

In May, root young shoots of 5–8 cm in gritty cutting compost.

Wild basil: how does it get through the winter?

Hardy to −35 °C.

• Fully hardy, to −35 °C: no protection needed.
• Leave the stems standing: they provide seed and shelter for insects.
• In a pot: stand it against a wall, on feet, so that it does not sit in water.

Diseases and pests

• Being crowded out: On rich soil it disappears among stronger plants and grasses. Choose a poor spot and weed around young plants.
• Powdery mildew: White powder on the leaves in dry late summers. Usually harmless; cut off affected leaves.
• Weak, floppy growth: Too rich a soil or too much shade. Do not feed and choose a lighter spot.
• Rotting: In wet, heavy soil in winter. Make sure drainage is good.

Through the year

• March: Cut back old stems. Sow and plant.
• April: Sow and plant. Keep young plants free of weeds.
• May: Take cuttings.
• June: Water young plants in dry spells.
• July: Flowering begins; bees and butterflies visit.
• August: Full flower.
• September: Last flowers. Planting. Mow a flowering meadow after the seed has set.
• October: Plant or divide.
• November: Leave the stems standing for winter.
• December: Rest.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Butterflies

Nectar for butterflies.

Did you know?

• Despite its name, wild basil is not a basil, although both belong to the mint family.
• The name Clinopodium comes from the Greek kline, bed, and pous, foot: the flower whorls were thought to resemble the knobs on bed legs.
• The Dutch name borstelkrans, bristle wreath, refers to the bristly bracts around each flower whorl.