Perennial Lettuce
Lactuca perennis
Family: Asteraceae or Compositae
What it is like
Lactuca perennis is a PERENNIAL growing to 0.6 m (2ft) by 0.3 m (1ft in). See above for USDA hardiness. It is hardy to UK zone 6 and is not frost tender. It is in flower from June to August, and the seeds ripen from July to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. The plant is self-fertile. Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil.
Height (m): 0.6
Where it is found
Rocky or other dry places, especially on calcareous soils.
S. Europe.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 3
Leaves - raw or cooked. The leaves are often blanched to reduce any bitterness. They are fairly acceptable raw in salads (even without being blanched), especially in late winter and spring when the flavour is quite mild. The leaves do become much more bitter in the summer, however, especially as the plant comes into flower.
Medicine
Rating: 2
Although we have seen no specific reports for this species, most if not all members of the genus have a milky sap that contains the substance 'lactucarium' and can probably be used as the report below details. The whole plant is rich in a milky sap that flows freely from any wounds. This hardens and dries when in contact with the air. The sap contains 'lactucarium', which is used in medicine for its anodyne, antispasmodic, digestive, diuretic, hypnotic, narcotic and sedative properties. Lactucarium has the effects of a feeble opium, but without its tendency to cause digestive upsets, nor is it addictive. It is taken internally in the treatment of insomnia, anxiety, neuroses, hyperactivity in children, dry coughs, whooping cough, rheumatic pain etc. Concentrations of lactucarium are low in young plants and most concentrated when the plant comes into flower. It is collected commercially by cutting the heads of the plants and scraping the juice into china vessels several times a day until the plant is exhausted. An infusion of the fresh or dried flowering plant can also be used. The plant should be used with caution, and never without the supervision of a skilled practitioner. Even normal doses can cause drowsiness whilst excess causes restlessness and overdoses can cause death through cardiac paralysis. Some physicians believe that any effects of this medicine are caused by the mind of the patient rather than by the medicine. The sap has also been applied externally in the treatment of warts.
Other
Rating:
Food Forest: Plants for Edible Forest Gardens and Food Forests.
How it is grown
Prefers a light well-drained sandy loam and a sunny position. Plants are hardy to about -25°c. For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is a clumper with limited spread.
Propagating it: Seed - sow April in a greenhouse, only just covering the seed. Germination is usually fairly quick When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Division in spring. It is best to pot up the divisions and keep them in a lightly shaded position in a cold frame until they are growing away well. Plant them out in the summer. Root cuttings in spring.
Best place to grow: Cultivated Beds;
Habit: Perennial
Hardiness: 5-9
Growth:
Soil: Light (sandy), medium
Shade: No shade
Moisture: Dry, moist
Things to keep in mind
Although no specific mention of toxicity has been seen for this species, many plants in this genus contain a narcotic principle, this is at its most concentrated when the plant begins to flower. This principle has been almost bred out of the cultivated forms of lettuce but is produced when the plant starts to go to seed.