Wild Lettuce

Lactuca virosa

herb

Wild lettuce (Lactuca virosa), sometimes called bitter or opium lettuce, is a tall, imposing biennial relative of garden lettuce that can shoot up to 5 or 6 ft in its second year, with prickly-edged blue-green leaves and a haze of small pale-yellow flowers. When any part is cut it bleeds a bitter, milky white sap (lactucarium) that dries to a brown latex - the substance behind its long folk reputation. It is a robust, weedy, easy plant for a wild corner, grown for its leaves and that milky sap. The first year is a low rosette; the towering flower stalk comes the second.

✅ Plant alongside

Good neighbors that attract beneficial insects or deter pests

• Lettuce — A close relative that shares the same easy, sunny, average conditions
• Calendula — An easygoing companion that brings pollinators to a wild or herb bed
• Dill — An airy annual that fills space around the rosette and draws beneficial insects

🛡️ Pest & disease prevention

Proactive ways to stop trouble before it starts — tap a name with an arrow for its full guide

• Aphids →

  Rinse colonies from the leaves and stems; the vigorous plant usually outgrows them

• Slugs →

  May chew the low first-year rosette in damp weather - use grit or traps

• Downy mildew →

  Give airflow and avoid overhead watering, as lettuce relatives can mildew in cool, wet spells

🌾 Harvest & storage

Harvest the leaves in the second year as the plant comes into flower, when the bitter milky sap is most abundant; cut the upper leaves and stems and dry them. The latex itself is traditionally collected by repeatedly nicking the flowering stem and scraping off the brown dried sap. Wear gloves, as the sap stains and the leaf edges can prickle. The leaves are intensely bitter and are not used as a salad green.

🥗 Nutrition & benefits

Wild lettuce is grown as a traditional herb rather than a food - its bitter leaves and dried milky latex (lactucarium) have a long folk history, taken as tea or tincture. It is too bitter to eat as a salad green despite being a lettuce relative; in the garden it is a dramatic, towering plant for a wild corner.

⚠️ Toxicity & safety

Use with caution. Wild lettuce bleeds a bitter milky sap (lactucarium) with mild sedative effects - even normal amounts can cause drowsiness, and large doses are dangerous and have rarely caused serious poisoning. It is far too bitter to eat as a salad green and is used only as a traditional herb in small amounts. Avoid it during pregnancy or alongside sedative medication, and keep it away from children and pets.